[installed the 450R carb and WOW.....!!!] - ATV Riders Forums - Honda, Yamaha, Suzuki, Kawasaki, Polaris, CanAm, Arctic Cat, Kymco ATVsPages:1 2
installed the 450R carb and WOW.....!!!
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Posted by: QuadJunkies
what A nice enhancement.....
The throddle responsose is gonna be VERY impressive!!
Im not sure what all the hype was about having to make modifications, but we were still able to keep the choke AND the Hot start can be nicely tucked away
I was a little on the fat side with my old Carb,Im now lean, ditched the Air box, I think I may have to change my gearing in fears I may wheelie over
It sounds soooooo much betterthan my stock Carb, I now know that my stocker was trashed for some time now after hearing how this sounds... I cant wait to try it at the track!!!
Anyone that can get there hands on one............. DO IT!! 
Posted by: Rico
How was fit and finish?? What did you have to do to get it to work.
Did I read it correctly that you DITCHED the airbox?? Meaning the filter is bolted directly to the carb??
Some say the 450R shocks are a must to put on a 400ex, even though the stroke is wrong, grinding has to be done, etc, etc.
Posted by: Dave400ex
Yes let us know about this. I am with Rico, I would be running the airbox for sure, so how did that mount up?
Posted by: khen
That's good news QuadJunkies!!! I just got mine in yesterday, but I'm still waiting for the 450R cable from servicehonda. I have a few questions:
1- What pilot/main jets did you use in the 450R carb and what did you have on your old one(for reference).
2- Did you use the 400EX fuel hose, or did you use the 450R's?
3- Did you have to modify the choke so it would clear the fuel petcock?
Posted by: yfz450admirer
I used the stock pilot jet and a 185 main jet, 4th notch on the needle, air/fuel screw 3 1/2 turns out. On the stock carb I ran the same set-up except for less turns on the air/fuel screw.
I used the fuel hose from the 450R.
The yellow plastic choke handle will not clear the petcock. My quad starts easily by just pumping the throttle 2 times before pushing the starter.
The hot start is not really needed, although I use it at times.
The carb works great on my track.
Posted by: QuadJunkies
would you like some pics and Ill sit down with Troy and give more details tonight on it if you like ? 
Yes, I thought Troy said he had to ditch the airbox, but Ill dbl. check on that
Fit and finish was VERY simple,its on good and tight,I still have the choke evenand the hot start is going to just be ziptied out of site.... now its all about just getting the jetting and pilot dialed in.... 
Posted by: QuadJunkies
quote:
Originally posted by yfz450admirer
I used the stock pilot jet and a 185 main jet, 4th notch on the needle, air/fuel screw 3 1/2 turns out. On the stock carb I ran the same set-up except for less turns on the air/fuel screw.
I used the fuel hose from the 450R.
The yellow plastic choke handle will not clear the petcock. My quad starts easily by just pumping the throttle 2 times before pushing the starter.
The hot start is not really needed, although I use it at times.
The carb works great on my track.
did you completley remove your choke or just cut the tab dowbn a bit?? Thts what he done to mine
Als, what Elev. and temps are you at right now??? Im at 2800 and its Averaging this wk in the 40's, we race in the 20's
Posted by: hondarider2006
I want to see some pictures. Sounds like a good mod that I might have to look into....
Posted by: QuadJunkies
quote:
Originally posted by khen
That's good news QuadJunkies!!! I just got mine in yesterday, but I'm still waiting for the 450R cable from servicehonda. I have a few questions:
1- What pilot/main jets did you use in the 450R carb and what did you have on your old one(for reference).
2- Did you use the 400EX fuel hose, or did you use the 450R's?
3- Did you have to modify the choke so it would clear the fuel petcock?
Ill get more info tonight 
Posted by: khen
Thanks QuadJunkies and yfz450admirer! I'm looking forward to trying this out, hopefully the cable comes in today.. I didn't think to order a 450R fuel hose though
Hopefully I can make do without.
Posted by: Rico
I forgot to ask you Tina... Why you didn't put this in our own 400ex forum........
YOu have the power woman..
also for me, check the clearance from the top of the carb to the gas tank. I run a clarke oversized tank and I don't think the carb is going to work with the MUCH larger tank....
Posted by: QuadJunkies
quote:
Originally posted by Rico
I forgot to ask you Tina... Why you didn't put this in our own 400ex forum........
YOu have the power woman..
also for me, check the clearance from the top of the carb to the gas tank. I run a clarke oversized tank and I don't think the carb is going to work with the MUCH larger tank....
I guess I could ......
Make Ill copy the info over there 
Posted by: QuadJunkies
Here are some pics I took...
We need to attach a hose clamp to keep fuel from leaking, re are rejetting tonight so I can ride it tomorrow at the track that has the Payette Round for WORCS...Maybe Ill get some video of it...
Posted by: QuadJunkies
there will be a hose clamp where that wire is .Troy said an Airbox will work, Il get more info in a few minutes on that 
Posted by: QuadJunkies
Im done with riding in mud(if I can help it that is lol) I dont run threw creeks ect so no air box will be fine for my application for now, in the future I may invest in an afteramarket box.
Posted by: QuadJunkies
Choke is stil attached just cut back some....Im sure overtime we will make things look a little nicer on the set up as well...
Posted by: QuadJunkies
Rico~~ heres the clearance question you needed.....sorry for the blur.. let me know if its too hard to see and Ill try and get a better one 
Posted by: 44oEX
see and you didn't believe me 
Posted by: QuadJunkies
well, so much for testing out my carb tomorrow.. I blew a head gasket while jetting.....It hasnt ran good during a race and had a weird noise, now we know what the other noise was.....
Im not sure if its due to a bad jug or the Gasket ect.... We may go back and just put my 426 back on...
I was REALLY looking forward to trying the 440 too...
Posted by: QuadJunkies
quote:
Originally posted by Rico
How was fit and finish?? What did you have to do to get it to work.
Did I read it correctly that you DITCHED the airbox?? Meaning the filter is bolted directly to the carb??
Some say the 450R shocks are a must to put on a 400ex, even though the stroke is wrong, grinding has to be done, etc, etc.
You could prol. come up with something, the intake boot was a little short and the air box on ours was pretty much already destroyed so no big loss on my end. You have to replace the fuel line and you have to hog out the intake boot. Thats about it ...!!
Posted by: ZSK
Get the headstuds
Posted by: QuadJunkies
quote:
Originally posted by ZSK
Get the headstuds
thats what I hear....
Head bolts and a flex Gasket or something like that....
Im not sure what kind of gaskets this kit cam with for certain but we will get Er figured out and if not then Ill just slap my 426 bakc in....Also, what about Vavle springs??? Im sure my 426 had some but not sure what they were
Posted by: ZSK
quote:
Originally posted by QuadJunkies
Head bolts and a flex Gasket or something like that....
That's what it took to get mine figured out. It blew the flexsteel on after about 18 hours, put a cheap kit in and it blew in about 3. I installed the HD headstuds, and the flexsteel gaskets and didn't have a problem. Race the rest of the season on it and numerous trail rides.
Posted by: muddy400EX
was the 450 carb easy to put on? did it require any mods? and does anybody know if it would do nething on a stock motor?
Posted by: QuadJunkies
quote:
Originally posted by muddy400EX
was the 450 carb easy to put on? did it require any mods? and does anybody know if it would do nething on a stock motor?
Did you read ANYTHING I posted and see ANY pof the pics???
That should be ALOT of info that your asking about.... 
Posted by: twisted threads
quote:
Originally posted by QuadJunkies
Did you read ANYTHING I posted and see ANY pof the pics???
That should be ALOT of info that your asking about....
LMAO!!!!!
About the head gasket......... I would just get some studs and see how that works. I have only blew one head gasket since my 440 has been together and I run stock head studs.
Posted by: khen
I got 450R carb installed today. It sounds really nice! The cable comes in tomorrow for it so hopefully I can go see what it does sometime this week. Here are few pictures of my installation.
I ended out pulling the vent tube off of the top, cutting it down and caping it and then drilling out the side vent instead like Laz suggested.. I found that otherwise my tank would be resting on it. I also did a makeshift choke and moved the airbox forward about an inch to make up for the shorter carb.
Posted by: khen
The carb is in there as solid as the stock one.. I did have to ream out the boots quite a bit to make them fit correctly, especially the airbox boot. Here's a side view of my makeshift choke, I just have to push up on it at the bottom where the 'L' bend is.
Posted by: QuadJunkies
NICE illustration!!! Thanks for posting some pics.!!.. mine were blurry....

Posted by: khen
quote:
Originally posted by QuadJunkies
NICE illustration!!! Thanks for posting some pics.!!.. mine were blurry....
Nah, your pictures look good.. I just never take pictures when I do my mods and people always PM me asking for pics. So I thought I'd be proactive this time.
I'm excited to hear another performance review of this carb. I was hoping to try mine out this week at the track, but mother nature suprised us with 4-5 inches of snow this morning.. 
Posted by: EXDUNER127
So the 450R carb just bolts right up to the 400ex, just like the 400ex carb did, without needing anything? Is the 42mm to big for a the 400ex with aftermarket cam and piston, and porting because the fcr only goes to a 41. So when i buy the 450r carb the only other thing i need is the gas line and throttle cable to make it work? How much did you guys get yours for?
Posted by: 44oEX
quote:
Originally posted by 44oEX
Some people just warm up the intake boot with warm ( boilling water ) and then jam the carb in there. it might work but that will pop out. So don't do it
The right way to do it is like yfz450admirer said ( i told him how )
take the intake boot off of the motor. then use a dremel or sand paper ( slower but cheaper then a dremel lol) or grinding rock on a drill or something, and make the hole in the boot a little bigger. don't go to big. On mine I still have to fight it a little to make it go in but it's just cause I got sick of sanding
. ones you have the hole the size you what ( make sure it's round so it won't leak ) put the intake back on the motor then work on the boot that goes from the air box to the carb. That one is a little harder cause it's only a thin wall, so you don't want to take to much out. Take out a couple mm if you can force the carb i then you good.
One's that is done you basicly done. see it's not hard it just takes a little time to get it the right size. The only problem I got was that the stock choke lever ( 450R ) it will NOT clear the gas line ( use the 450 one just cut it a little sorter so it won't kink. and use a small clamp to hold it on the petcock) The choke thing is not that big of a deal. you don't need it for summer riding. I have to have one ( I made a costom one ) but it's only cause the winter wheater is around -10 to -20
You can use ( you have to ) the stock 450R gas cable with the EX's trottle.
Know for how it runs. well yes Rico if you give it gas when it's warming up it will stall. But that is kind of a good thing. you have to let the motor warm up before you ride anyway right.
But as you don't have to give it any gas anyway. unlike most quads I've seen, one's it starts it will run on it's own with no gas and it won't stall on it's own. ( if you jetting is any good ). Mine runs really smooth on idle. and it's a 500 stroker with a wild grind cam. so it sould be even better on a normal size motor ( 400-440)
and the idle is smooth from cold start up all the way up to the end of a couple hour run.
One's the jetting was good the trottle risponce is really good. I can give it full trottle when idling and it will rev up right away. as long as you pilot screw is set properly you won't have any problem. if it's not well then it will complain a little but I mean it's normal if the jetting is off.
speaking of jetting. I was having trouble with the stock carb on the 500. I could just not get it like I wanted. it was always complaining. well the 450 carb is easy to jet and even if you are not spot on with the main or needle it's no big deal. ( well it is but I mean it will still run good so check the plug. )
And as for falling of I didn't have any problem yet. and this is not a show quad it is riden hard. and no dunes it's a rough trail and pit ( jumps ) riding. just make sure the boot is not to tight. And put the clamp pretty tight. but I would not worry about the carb falling off.
I think I awnsered all the Q?'s if I misted any let me know.
oh and for jetting start of with a stock pilot jet and something around 170 for the 440. then work from there.
custom choke
http://www.imagestation.com/picture/sraid153/pcd6b18360272bc6298a177229d033903/f5919b89.jpg
side. you can see the sorter gas line and the clamp I used. And how tigh the choke is
http://www.imagestation.com/picture/sraid153/p72ee5b2348811cf076dd64a6737e4437/f5919b83.jpg
Posted by: 44oEX
there you go that sould answer all the Q?
Posted by: QuadJunkies
quote:
Originally posted by 44oEX
there you go that could answer all the Q?
WEll..................I think all this about covers it........!!! 
Posted by: Rico
So your saying it just bolts up and your ready to ride...

Posted by: QuadJunkies
quote:
Originally posted by Rico
So your saying it just bolts up and your ready to ride...
Well. I know mine is !!!
We got the Duncan racing kit installed tongiht, I have two more runs on it early in the morning before I go race it tomorrow night, we may some of the changes listed and WOW... I think Im gonna REALLY like this set up...
Ill let you know how it runs tomrorow!
Posted by: QuAdEr 317
i did read all this but i still dont understand if you can stil use a airbox cuz in ur picture u have the boot directly to the filter n i would still need to use the airbox
Posted by: khen
quote:
Originally posted by QuAdEr 317
i did read all this but i still dont understand if you can stil use a airbox cuz in ur picture u have the boot directly to the filter n i would still need to use the airbox
You can use the airbox you just have to move it forward about 1". Here's a picture of how I mounted mine for now. I just put a big washer on the existing mount bolt to hold it down.
Posted by: QuadJunkies
Well, I raced half the night on it(decided to run the Preedator the rest of the night,didnt like my tire set up) and its a great add on! The throddle response it sooo good....
When I raced inthe heat race it was sputtering and sounding as if I was hittin my Rev limiter but it just needed more fuel and that took care of that.. We still want to make some changes to make it all fit better but I have no complaints. GREAT upgrade to make!! 
Posted by: khen
Cool! that's good news QuadJunkies.
Do you recall what jets you ended out with? and what needle position?
Posted by: QuadJunkies
quote:
Originally posted by khen
Cool! that's good news QuadJunkies.
Do you recall what jets you ended out with? and what needle position?
Ill find out tonight from Troy just to make sure ,but I know I had to jet down a little and I think same with the pilot and a full turn on the fuel . I needto take it out and runn it in 5th gear so I can get a full feel for it wide open
but I think were pretty darn close if not dead on ...
Posted by: QuadJunkies
My jetting is a 180 main,it came stock with a 190
needle is set one position leaner than stock
pilot is a 45 Stock was a 38
(weird)
Fuel screw -2 turns out
Isnt that weird, it wouldnt idle with a 38-40-or a 42, 45 starts up and runs like a champ.! Temps 35 degrees ran good 40-45 it runs fat.
Posted by: Hotdog
i seen that service honda is only selling them for 165 bucks. that cheap.
Posted by: 44oEX
quote:
Originally posted by QuadJunkies
My jetting is a 180 main,it came stock with a 190
needle is set one position leaner than stock
pilot is a 45 Stock was a 38
(weird)
Fuel screw -2 turns out
Isnt that weird, it wouldnt idle with a 38-40-or a 42, 45 starts up and runs like a champ.! Temps 35 degrees ran good 40-45 it runs fat.
a 450R comes stock with a 118 main and a 45 pilot
Posted by: QuadJunkies
quote:
Originally posted by 44oEX
a 450R comes stock with a 118 main and a 45 pilot
well, this Carb had a 190 in it when we got it from our freind ... Ill dlb. check on it I know his honda is pretty modified so ill dlb. check and make sure I had that correct...

Posted by: 44oEX
well if it's modded a 190 makes sense but not stock
Posted by: QuadJunkies
quote:
Originally posted by 44oEX
well if it's modded a 190 makes sense but not stock
Well I asked him and he said nothing had been done to the Carb ..So now Im not sure why it had a 190 in it
. Thats why my hubby assumed a 190 was stock....
lol
So now my question to you all is... Can this Carb being that much BIGGER HURT performance?? Maybe not so much on a Modified quad but what about ones that are just stock or piped?? Ive heard that sometimes when you go bigger Carb it can hinder your gains somewhere between top end to bottom......This mihgt be a good thing to post for those peeps considering one ...
Posted by: Metzroth
Yeah I'm looking into it but all I will have is HMF full system K&N Air filter and open airbox lid. Will the 400ex jets work on this carb or will I need to buy another jet kit. Will it hurt performance at all if jetted correctly? Where is the cheapest place to buy the carb fully assembled or with all the parts and I can assemble it.
Posted by: 44oEX
it souldn`t hurt the performance even on non modded quad. we put my 400ex carb on a stock 300ex and it did a big diffrence.
Posted by: Metzroth
k then i think i will look into one. My local dealer (I don't really like) can get me a 450r Carb for $226. Can i get one cheaper than this somewhere?
Posted by: khen
quote:
Originally posted by Metzroth
k then i think i will look into one. My local dealer (I don't really like) can get me a 450r Carb for $226. Can i get one cheaper than this somewhere?
Yes, buy it from servicehonda.com you can get it for $165. You'll also want to buy the 450R throttle cable and fuel line.
Posted by: Metzroth
Stupid of me but...I can't find the parts on there website. Could you send me a link to it? Also how much are the throttle cable and fuel line?
Posted by: 44oEX
I forgot to say that yes the 400ex jet and the 450R jets are the same ( different size but same kind ) so yes your jet kit will work just find.
as for the carb look in the for sale section. you could get a used one for really cheap.
Posted by: khen
quote:
Originally posted by Metzroth
Stupid of me but...I can't find the parts on there website. Could you send me a link to it? Also how much are the throttle cable and fuel line?
Click on parts at the top of the page and then click on the Interactive Pricing Page link in the middle of the page. You should get a small pop-up page that you can enter the part numbers in and add it to a cart. Click on the OEM Hard Parts link to get to the online parts manuals.
Im with 44oEX though.. you can pick up lightly used carbs for even more of a bargain.
Posted by: Metzroth
well im lookin for a used one. If anyone has one PM me and im interested.
Posted by: lelandjf
Is the carb on the crf450 the same as on the 450r? While searching ebay for a 450r carb, I saw an adapter to put the crf450 carb on the 450r. If this is accurate, would it make sense to put the crf450 carb on a 440ex?
Here is what I saw on ebay:
http://cgi.ebay.com/ebaymotors/ws/e...sspagename=WDVW
Posted by: 44oEX
the crf carb is a FCR and the 450R carb it just a kiehin.
The CRF carb would be alot better. But I don't know if the fit would be the same or not. Cause you have to clear the gas tank and stuff.
Posted by: yamablaster24
My friend is selling a brand new stock 450r carb if anyone is interested.
Posted by: QuadJunkies
I get asked about the 450r carb alot.
I thought for awhile, I would post a sticky on this topic so that it may come in handy for others.
Hope this helps 
Tina
Posted by: krt400ex
quote:
Originally posted by khen
Nah, your pictures look good.. I just never take pictures when I do my mods and people always PM me asking for pics. So I thought I'd be proactive this time.
I'm excited to hear another performance review of this carb. I was hoping to try mine out this week at the track, but mother nature suprised us with 4-5 inches of snow this morning..
snow sounds good for testing 
Posted by: krt400ex
quote:
Originally posted by khen
You can use the airbox you just have to move it forward about 1". Here's a picture of how I mounted mine for now. I just put a big washer on the existing mount bolt to hold it down.
so how did u move it closer??
Posted by: kris_400ex
what year 450r carb are you guys useing? i know they changed them in 2006 is the older ones better or the newer ones? or it doesn't make a difference?
Posted by: 44oEX
the carb used in this post was the 42mm carb, the one on the 04-05, the 39mm FCR carb on the 06-07 would be better, and would probabaly be easyer to make it fit in the intake boots since it's smaller, don't know about the clearance for the gas tank and stuff tho.
Posted by: Troy15x
I know that this is not the 4 sale section but i have a 450r carb and custom adapter for sale for $150 shipped
I will try and get some pictures posted this weekend
We tried different designs but the airboot always fell off on MX
This one works and keeps stk airbox
Posted by: 44oEX
if you bore out the boot enought ( with a dremel or something ), make it big enought that the carb can pop right in and not have to be forced on...it will stay on for mx
Posted by: adamsortega
does anyone know about the throttle control position? do i need it?
Posted by: 44oEX
if your talking about the trottle position sensor, no you don't need it, just tape off the wirring or the connection
Posted by: adamsortega
does anyone have any suggestions on jetting my new carb?...i ride in nj, ny, and pa...i have a 440 kit, stage 2 hotcams, yoshimura full system, and im riding with no airbox cover...
Posted by: 44oEX
probably start around a 180...and go from there, it sould be a good starting point
Posted by: QuadJunkies
quote:
Originally posted by adamsortega
does anyone have any suggestions on jetting my new carb?...i ride in nj, ny, and pa...i have a 440 kit, stage 2 hotcams, yoshimura full system, and im riding with no airbox cover...
I run the same, I am jetted at 180 right now,elev 2800ft.
Posted by: yfzfelix
after spending many hours sanding and grinding my carb boot for a 40 mm fcr for my 460ex I wish someone sold an aftermarket boot with a larger ID because I sure would buy it, I could not see the sense of installing a 40 mm carb on a boot with a 38mm hole in it so I had to open it up and man thats alot of work and I'm still not happy with it so I am going to make my own
Posted by: 44oEX
well the 450R carb is a 42mm, try to get that to fit lol....it's work, but well worth it in the end.
Posted by: Quadjunkie
Would this upgrade still apply if you don't have the 440 kit? I like the idea, ie more air and fuel, sounds great.
Posted by: j450rking
quote:
Originally posted by QuadJunkies
well, so much for testing out my carb tomorrow.. I blew a head gasket while jetting.....It hasnt ran good during a race and had a weird noise, now we know what the other noise was.....
Im not sure if its due to a bad jug or the Gasket ect.... We may go back and just put my 426 back on...
I was REALLY looking forward to trying the 440 too...
how dose the 426 compare to the 440?
Posted by: 44oEX
quote:
Originally posted by Quadjunkie
Would this upgrade still apply if you don't have the 440 kit? I like the idea, ie more air and fuel, sounds great.
yeah it would still help the motor breath better, I had it on my 500ex at first and it really helped, but after I sold the motor I only had a stock bore 400ex and it still help it out.
Posted by: Wshunew2004
Anyone have a 450R Carb for sale ? I'm willing to pay I looked on ebay man but jeeze people are so proud of those things man ?
Posted by: 44oEX
I have one...how much you willing to pay for it?
Posted by: Wshunew2004
Well i'm just trying to figure out the best fuel setup on my bike it's pretty much stock other than the cam and exhaust !! So I'm not really sure what are you wanting to get for it ? Around a $100 Bucks or so ?
Posted by: 44oEX
you have a PM...nice EX by the way
A 450R carb it a nice upgrade, it will help your motor breath better...and for the price it's a nice investment
Posted by: sc400ex_rider
anyone put a drz400 carb on its a 40mm fcr or a yfz450 carb on. the o6 450r has a fcr now too. 04 04 have the old style.
Posted by: dheavychevy38
I picked up one of these carbs with no cables and ordered the throttle cable but what do i do with the other threaded hole on the other side just plug it or do i have to get some kind of cable for that to Thanks Denny
Posted by: dheavychevy38
I picked up one of these carbs with no cables and ordered the throttle cable but what do i do with the other threaded hole on the other side just plug it or do i have to get some kind of cable for that to Thanks Denny
Posted by: dheavychevy38
I picked up one of these carbs with no cables and ordered the throttle cable but what do i do with the other threaded hole on the other side just plug it or do i have to get some kind of cable for that to Thanks Denny
Posted by: hondaracer57
im pretty sure its for the hot start cable i think u can just plug it cause u dont need it i would just go up to search and type in 450r hotstart and u will find a thread about it...
Posted by: 44oEX
No don't just plug it, you need the small plunger that goes inside there, buy a hotstart block off, or just get a 450R hot start cable, when the warm summer weather gets here, you'll be glad you have it.
Still have mine for sale if anyone is looking for one.
Posted by: dheavychevy38
Where can the hot start block off be found i have searched with no luck thanks denny
Posted by: 44oEX
I don't know who sells it, I know the YFZ's FCR carbs come with a hotstart block off, It looks the same as the TRX carb hot start, but I don't know if they are the same treads or not
Posted by: EXSailor
does anyone know if the CRF 450r carb is the same? I found one from an 02 real cheap, but I don't want to get it if it won't work.
Posted by: EXSailor
quote:
Originally posted by 44oEX
the carb used in this post was the 42mm carb, the one on the 04-05, the 39mm FCR carb on the 06-07 would be better, and would probabaly be easyer to make it fit in the intake boots since it's smaller, don't know about the clearance for the gas tank and stuff tho.
would having the 39mm fcr carb be an improvement? i'm not a great mechanic, if so, why?
Posted by: 44oEX
well the TRX 42mm, would be better then the stock ex one, but the FCR would be better then the 42mm yeah, don't know how easy or hard they would be to put on tho.
Posted by: EXSailor
ok, thanks for clarifying, I just read this whole thread yesterday and now i'm seriously considering doing this mod.
Posted by: 44oEX
well my carb is still up for sale if your looking for one
Posted by: joeb23
is the throttle sensor needed?
Posted by: hondaracer57
no all the wires hanging off the carb just zip tie them outa the way...
Posted by: Hammer trx450r
I have a stock 450r carb for sale
Posted by: joeb23
quote:
Originally posted by hondaracer57
no all the wires hanging off the carb just zip tie them outa the way...
do you know if this would be the same for the crf wiring harness and the 450r carb?
Posted by: hondaracer57
no sorry i have mine on a 400ex but im guessing that ur not gonna need them but y aint u useing the crf carb ive heard they are better cause it it a 39mm FCR...
Posted by: joeb23
I just decided to use the 450r carb it was a little cheaper.
Posted by: Quadtrax
WOW ..... This is the best thread I have ever read. I have a 416 with ported head, full exhaust. This thing has been uncarbed ever since the first bore, (406). I bought two 450R carbs about 6 mo. ago and was worried about the install. I have no doubt this is what I need to make my EX rip. Just to make sure on a couple of things I want to reask a few questions.
1. .. Just bore out the intake?
2. .. I do XC, what jetting do you think? (HMF exhaust)
3. .. I use a 50/50 mix of 112 race gas and 91 pump gas, is this still good mix?
I think this will be enough to get me started. Thank you for all the info in this thread. I'm sure I will have more questions to come.
Posted by: hdavis21
ive got one ont the way lookin forward to gettin it on, but how is it supposed to change the sound? will it have that little whistle out the exhaust that 450's have? might be a DA question just wondering.
Posted by: flauge
To me it had more of that intake sucking sound at idle and a lil more growl at Wot..
Posted by: Got Boost
how much for that carb? I am interested, 39mm or 41mm?
Posted by: krt400ex
i think that the 450R carb is a 42 millimeter. the '06 and up is a 40
Posted by: Hammer trx450r
True but the 06 is an FCR
Posted by: krt400ex
quote:
Originally posted by Hammer trx450r
True but the 06 is an FCR
yes i kno...but believe it or not. i have heard better things about the older carbs on the modded EX's than the FCR's
Posted by: Got Boost
ok how much of a power increase will I gain with 440 kit, 12.5:1 piston, st.2 hc with the 04 carb?
Posted by: 99426ex
wassup yall.. just got my 450r carb ($102.00 shipped) getting my throttle cable tomorrow.. just curious if anyone did anything with the heater assy. on the carb.. i went of service honda and checked the exploded view of the carb.. i was wondering if anyone used it or what it's for .. also does anyone use the hotstart cable.. if so how?? where do u hook it up to??.. thanks yall .. good info. all around this forum..
Posted by: sc400ex_rider
the 04-05 450 r carb is 170.00 at service honda. the 06-07 is 800.00 which one do you think is better
Posted by: krt400ex
quote:
Originally posted by Got Boost
ok how much of a power increase will I gain with 440 kit, 12.5:1 piston, st.2 hc with the 04 carb?
a rather largely noticeable difference all acrossed the board. this is what i have been told...i have never done it myself.
Posted by: flauge
quote:
Originally posted by Got Boost
ok how much of a power increase will I gain with 440 kit, 12.5:1 piston, st.2 hc with the 04 carb?
From what Iv'e heard you'll notice more of a gain when you put it on a 440 compared to the smaller bores..You'll be real happy you bought it...
Posted by: Hammer trx450r
got one! 150 shipped
Posted by: 400ex124
could i just snip the wires for the throttle response sensor or whatever its called) off? also can i do the same with the other ther wires on the carb? if not let me know what to do.....plz!!
Thanks Tyler
Posted by: 44oEX
yes
Posted by: joeb23
so the 450r throttle cable fits fine in the 400ex throttle box? And what about the hot start how do you hook that up?
Posted by: 44oEX
yeah the trottle boxes are all the same on all the sport honda's, as for the hot start, you'll have to get a clutch perch that you can connect it to, or a block off for if if you don't plan on using it. Or you can just hook the cable into it, and if you don't plan on using it, just let the cable loose under your fenders somewheres
Posted by: Hammer trx450r
http://cgi.ebay.com/ebaymotors/2004...sspagenameZWDVW
04 trx450r stock carb WITH BRAND NEW THROTTLE CABLE
EBAY ITEM #280100558941
Posted by: wrobben
so since u can use the stock 400ex jets in a 450r carb, but just diffrent size jets, does that mean that a Dynojet Jet kit for the 400ex would work in the 450r carb?
Posted by: KJS
YES SAME MODEL # FROM THUNDER PRODUCTS
Posted by: smartypants
I have a 42mm carb for sale if anyone is interested, comes with all the jets needed. Send me a PM if interested.
Posted by: feelthisroost11
I have a question..i was looking for a 450r carb for my 440ex and i came across a 03 crf 450 carb and i was wondering if it was a trx related carb? Would it be the same installation as a trx carb?Do i need any adaptors if so? Thanks
Posted by: feelthisroost11
I have a question..i was looking for a 450r carb for my 440ex and i came across a 03 crf 450 carb and i was wondering if it was a trx related carb? Would it be the same installation as a trx carb?Do i need any adaptors if so? Thanks
Posted by: QuadJunkies
quote:
Originally posted by Got Boost
ok how much of a power increase will I gain with 440 kit, 12.5:1 piston, st.2 hc with the 04 carb?
I have similar set up. I was told 4 HP gain..
Seems a little on the high side , but I think there was some testing done and thats the numbers it was pulling .
The gains are very noticiable !
Posted by: j450rking
were can i get a hot start block off? or can i just plug the hole? i have seen people just put a plastic plug in the hot start hole. is that ok?
Posted by: j450rking
quote:
Originally posted by 44oEX
No don't just plug it, you need the small plunger that goes inside there, buy a hotstart block off, or just get a 450R hot start cable, when the warm summer weather gets here, you'll be glad you have it.
Still have mine for sale if anyone is looking for one.
were can i find a hot start block off? i relly need to know
also what would it do if i just plug the hole?
Posted by: honda6490
quote:
Originally posted by QuadJunkies
I have similar set up. I was told 4 HP gain..
Seems a little on the high side , but I think there was some testing done and thats the numbers it was pulling .
The gains are very noticiable !
Definatly get a 11:1 piston, then you can run pump gas if you please.
Posted by: Ruby Soho
if i put a 450r carb on my 440ex, would i notice anything EVEN though i have a stock exhaust? (pipe coming in the future when i can some $$$)
Posted by: j450rking
you should and if you are going to get a pipe later your going to want to get a carb then anyway
Posted by: 1965 honda
quote:
Originally posted by Ruby Soho
if i put a 450r carb on my 440ex, would i notice anything EVEN though i have a stock exhaust? (pipe coming in the future when i can some $$$)
r you really runnin a stock exfaust on a 440
Posted by: Ruby Soho
yes. bought it like that.
Posted by: 1965 honda
thats crazy, i always thought that the was the first mod. but i guess not.
Posted by: Ruby Soho
i would have done a pipe first, but i bought the quad like this. its got no quite core in it with an exhaust tip. so its ALITTLE better than completely stock. but i know an exhaust will really let this thing scream.
so i think im gonna do it considering i can get one for like 50$
Posted by: 1965 honda
what are you getting for 50$ i need a knew one mine rotted out for some reason. im having a few problems with mine right know
Posted by: Ruby Soho
i can buy my neighbors stock 450r carb for alittle under 50$
Posted by: j450rking
thats cheap get it !
Posted by: Ruby Soho
im going to get it. but should i put it on before i get the exhaust?
Posted by: j450rking
yeah put it on it won't hurt
Posted by: Ruby Soho
do you think ill notice any gains or better throttle response?
Posted by: j450rking
you should.
have you read any of this thread?
Posted by: Ruby Soho
most of it. but i dont have an exhaust, thats why im asking
Posted by: j450rking
i'm shur it will
Posted by: Ruby Soho
cool, thanks dude
Posted by: EX Stud
hey guys look what i just won on ebay
ebay
what do you guys think?
do i need to order anything specail for it?
Posted by: Ruby Soho
looks good dude.
question for installation.
if you want to install one on a 400ex, you have to use a drememl and make the boot alittle bigger and then it slips on, then move the airbox back 1 inch. thats all and then i just need to jet it and ride right?
Posted by: EX Stud
i already have my airbox removed anyway...
but do i have to buy a 450r throttle cable?
Posted by: dragex400
Yeah, you need to buy the 450r throttle cable and it fits your throttle on your bars, so you just need the cable. I read posts on here of guys filling the hot start with silicone or putting a bolt in the hot start, that doesn't block it off enough it will still leak air and you'll never get the bog out. IF the carb doesn't come with the hot start cable and you don't want to hook it up, buy the hot start plunger from servicehonda.com and put the plunger in, that will block the hot start off correctly. Also, do not cut or dremel the end of your boot that goes from your carb to your intake ports. If you dremel it or cut the boot it will never seal right. Take some time and force it onto the carb it will go on and it fits really tight but work it on. If this part doesn't seal, again, you never get the bog out and you'll have tons of trouble jetting. For the air intake side, do whatever you can to make it fit right. If you have any problems pm me and I'll help you out. I got mine tuned in perfectly, no bog at all and response is unbelievable.
Posted by: j450rking
how would i tell if i have the hot start plunger or not right now all i can tell is that there is a black plastic peace screwed in to the hole
Posted by: dragex400
The black plastic piece that is screwed in there should be the boot that holds the plunger down. The hot start cable connects to the plunger and when you use the hot start it lifts the plunger. IF the cable didn't come with the carb I doubt that the plunger is in there. To check, unscrew the black plastic piece and see if there is a black cylinder in the bottom of the hole, if there is you can pull it out and look at it, you can pull it with a small pair a needle nose pliers. If it is there you want to pull it out and make sure there is a neopreme ring on it so it seals. If the cable is on it and the plunger is there just snip the cable and leave it in, unless you want to use the hot start, but it is not needed. Also look in the fuel line fitting and see if there is a little mesh screen in there.(looks like a small thimbal). Also you will need a fuel line from a 450r. Your stock 400 fuel line will not work, but the 450r fuel line will fit right on. Also you will have to trim back the yellow choke lever.
Posted by: eliasxr400
Do you think a 450 carb will be worth it with my motor mods?
11.1 std. bore piston, stage 1 hotcam, K&N with air box lid removed, and HMF slip-on.
Also will a Yamaha yzf450 work?
Posted by: j450rking
you should get a good jump
Posted by: PinkRider
I have a 2003 400 ex now a 440, and i got the 450r carb, how did you get the carb to work out referring to the connection between the gas tank and carb? I am having a hard time with that one...help please...
Posted by: flauge
Talking about the gas line? I used a small barbed brass fitting... One side thats sized to the 450r line going to the carb, and the other side thats sized for the 400ex goes to the gas tank....You oughta be able to find it at a auto parts store or maybe even Home depot or something...
Nice looking bike btw.
Posted by: dragex400
Buy the 450 fuel line from http://www.servicehonda.com The part number is 16956-HP1-000. Make sure to send them an email saying that you want them to send this by mail instead of Fed. Ex. Fed. Ex. is 12$ shipping an US Mail is about 2$. The fuel line is formed so it will not kink. The petcock side is small to fit the petcock and the carb side is huge to fit the carb fitting. The fuel line is speacially formed and the 450R has about the same gas tank as the 400. I put a hose clamp on each connection just to be on the safe side. Hope this helps.
Posted by: sc400ex_rider
i just added the 450 carb and its awesome!!!! i used auto 3/8 fuel line, i screwed a (car) spark plug in the hose to open up one end. i used a hose clamp for the tank. i also cut off one barb of the petcock nipple (lol) not sure if it matters. i used a yfz cable put both jam nuts under or inside the carb to get good free play then adjusted it for WOT. for the hot start i tapped the hole that is behind the throttle plate (engine side) and put a allen wrench set screw in the hole. dont tap all the way just half to start it that way it will snug down and use lock tight!!!!! i used a door panel clip with the funny barbs to fiil the hotstart plunger hole, looks stock. also this idles great i can adjust it down to a stall. heard many probs of idling high, might be cable tension or a vaccum leak. running a 160k main stock pilot 2 turns out on mixture. it will stumble if you punch it WOT at idle in neutral. but in gear this thing is great. might try to adjust the mixture or take some accelertor pump out. oh i also cut off the top vent nipple flush where it hits the tank tapped and filled with allen set screw drilled and used the side vent port. otherwise this is a great package check my sig
P.S. nice pink quad
Posted by: PinkRider
thanks guys for all the help!!! Another question, what about the choke lever hitting the 400ex fuel tank petcock??? thanks
!
Posted by: PinkRider
Okay guys, I have a picture of my problem that way you know what im talkin about... here ya go, hope this helps
http://i28.photobucket.com/albums/c235/Daniellecheri/DSC03183.jpg
Posted by: sc400ex_rider
the choke lever is going to haft to be removed. you really dont need it just pump it a couple of times to squirt fuel in there. dont forget to grind the lip off the air filter boot in side and bottom rib that hits the subframe. use a beer bottle to enlarge the hole. also move up your air box alittle about 1/4" use a large washer to hold it down and i used a 1/4" x 1/4" piece of vacumm line on the bolt under the washer to keep it sqaure. 
Posted by: flauge
We dont need no steenkin choke! Its summertime!
lol.
When I got my 450 carb it was already set up for a 400. The factory choke lever was taken off and replaced with a thick peice of wire. Looks like the dude clipped a peice off a clotheshanger and shaped it to fit. It works good but I hardly use it tho. Like sc400ex said, just pump it a few times and it'll crank right up.
If i get my camera in sometime this week I'll try to take a few pics. Maybe that'll help a lil 
Posted by: zje400ex
can i put a 450r carb in, or do i need engine mods?
Posted by: sc400ex_rider
cant hurt plus you have full exhaust. just keep adding to your package.
Posted by: PinkRider
Yes flauge pics would help out alot. thanks!
Posted by: sc400ex_rider
heres a good thread with some pics
http://www.exriders.com/vbb/showthr...rb&pagenumber=1
Posted by: PinkRider
Thanks alot for that link, i think ima try to rig something together this weekend! Ill let everyone know how it goes. please more suggestions if any one has any!

Posted by: flauge
Heres a quick pic i took of my choke lever. I'll try to take another one later today from the top of the carb.
http://i201.photobucket.com/albums/aa177/nickvanacore/honda400ex004.jpg the lil metal peice with the rubber at the end is it.
Posted by: Got Boost
ok guys I found a new carb from service honda, $170 and my local shop was $650. I have a few questions, what size is the stock 400 ex carb (mm), and what is the new carb (450 R) in mm? I havent read the thread so what performance gains can I expect, and what do I need to buy other than the carb to make it work? Thanks for the help.
Posted by: sc400ex_rider
here is more pics of the choke lever
http://i140.photobucket.com/albums/r20/starcraftier1/exchoke.jpg
http://i140.photobucket.com/albums/r20/starcraftier1/dsc02175.jpg
http://i140.photobucket.com/albums/r20/starcraftier1/dsc02178.jpg
http://i140.photobucket.com/albums/r20/starcraftier1/carblabeled.jpg
http://i140.photobucket.com/albums/r20/starcraftier1/airbox-1.jpg
Posted by: H_W
quote:
Originally posted by Got Boost
ok guys I found a new carb from service honda, $170 and my local shop was $650. I have a few questions, what size is the stock 400 ex carb (mm), and what is the new carb (450 R) in mm? I havent read the thread so what performance gains can I expect, and what do I need to buy other than the carb to make it work? Thanks for the help.
The stock carb on my 400ex was a 36mm and I think the new ones are 38mm, but I am not sure. The 04 -05 450r carb is a 42mm and the 06-and up 450r carb is a 40mm FCR carb. The yfz450 carb is a 39mm FCR carb. FCR carbs are the best performance wise. That is why the crf and yz 450 dirt bikes come stock with FCR carbs. FCR carbs are a little more expensive. I paid right at $440 for mine from C&D Racing. I told them what was all done to my bike and they jetted it for me. When I got it all I had to do was adjust the fuel screw alittle and ride. The carb was the last thing I did to my 400, and let me tell you it was a night and day difference. I was very pleased with the performance.
Posted by: 2001400ex
So from the little bit of reading I have done I have gathered that you need a 450R throttle CABLE in order for the 450R carb. to work on a 400EX - correct?
Is that all? I realize there is a choke issue but that is the least of my concerns at the moment.
And isn't there something with the hot-start that we can make work from the 450R carb. onto our 400EXs?
I would read more but this rebuild is wearing me at and I am just too lazy to read through 17 pages! The original poster should edit the first post on how to do a complete conversion. (Just a thought!)
Thank you.
Posted by: Sandman69
It really is that easy. Yes you have to have a new 450R cable ( which I suggest EBAY) and new fuel line and your ready to go. Dont need to worry about the hot start as you dont need to hook it up at all. Just extra wires. That's all I did and works awesome. Well after all the tuning and jetting.
Posted by: 2001400ex
Thanks for the reply.
New fuel line for what? That is one thing I do not think I read. What kind of fuel line (400EX? 450R? What?)
Posted by: Sandman69
the fuel line from the pet cock on the gas tank to the carb. you will need to get the 450 fuel line as the stock 35mm doesnt fit. Of course your kit may have come with the new line, mine did not.
Posted by: 2001400ex
Ah that fuel line, duh! Mine is sitting in the basement so if it's not in my face right now it's out of sight out of mind. 
I will be picking up the 450R fuel line shortly then. Thanks!
Posted by: phat1478
is it nessicary to remove the hot start? does anyone know the size of the 450 fuel line
Posted by: zrpilot
No, just plug the hot start hole.
Use the fuel line from the 450R.
Posted by: ZJTurbo
Is it still possible to take the choke off on the 450R carb??
-Ben
Posted by: zrpilot
quote:
Originally posted by ZJTurbo
Is it still possible to take the choke off on the 450R carb??
-Ben
the '04-'05 carb does not have a choke that sits in the air stream like the 400EX does, instead it use an enrichment circuit as the choke. So to answer your question, no it is not possible to remove the choke because there is not one to remove!
Good question!
Posted by: Brehmmotorsport
I still have alot of people asking but no clear responses on what size carb to get. I am stock with full exhaust and kandn. will the 42 work good or should i look for a 06 07 year carb.
Posted by: 44oEX
Well the 06-07 39mm FCR is better then the older 42mm regular keihin, for any applications...if you can get a FCR go for it.
Posted by: 05trx400exridr
I just read through the entire thread but there still seem to be a couple shady areas.....
*Will this help out my stock 400ex if i pick up a white brothers E series full exhaust system?
*Will either the 400ex or 450r pilot jet work for me?
*What about the main jet, will I need something between the 400ex and 450r sizes?
Posted by: zrpilot
quote:
Originally posted by 05trx400exridr
I just read through the entire thread but there still seem to be a couple shady areas.....
*Will this help out my stock 400ex if i pick up a white brothers E series full exhaust system?
*Will either the 400ex or 450r pilot jet work for me?
*What about the main jet, will I need something between the 400ex and 450r sizes?
1) yes, especially if future mods are forth coming
2) you might be OK with the stock 450R pilot, I had to go to a 50
3) Mains will be bigger, 165-175...
Posted by: Ruby Soho
on the 450r install, do you have to modify the boot that goes from the engine to the carb?
Posted by: zrpilot
yes it needs to be ground down some.
Posted by: thisperishedmin
my rides got a ported and polished stock carb. my question is...would i see an improvement in performance and/or reliability if i used a 450r carb? Currently, the stock carb choke tends to bounce itself on after a while riding too, which is a bit of a ****in bother to say the least.
Just curious how far off itd be on jetting, if id be loosing power, gaining power, etc.
thanks for any insight!
Posted by: thisperishedmin
my rides got a ported and polished stock carb. my question is...would i see an improvement in performance and/or reliability if i used a 450r carb? Currently, the stock carb choke tends to bounce itself on after a while riding too, which is a bit of a ****in bother to say the least.
Just curious how far off itd be on jetting, if id be loosing power, gaining power, etc.
thanks for any insight!
Posted by: zrpilot
The 450R carb does not have the traditional choke, it uses an enrichment circuit, so should solve that problem.
If you use the 450R carb, it will have to be rejetted.
As far as power goes, I'd guess you wil be gaining.
Posted by: Ruby Soho
zrpilot, i read your thread about the install. but im not quite sure what exactly you did to make it all work out. i understand the hotstart plug and all that but the hole boots and not moving the airbox thing im kinda confused on.. could you explain that alitte better?
Posted by: zrpilot
quote:
Originally posted by Ruby Soho
zrpilot, i read your thread about the install. but im not quite sure what exactly you did to make it all work out. i understand the hotstart plug and all that but the hole boots and not moving the airbox thing im kinda confused on.. could you explain that alitte better?
The 450R carb is shorter then the stock carb and the intake and airside of the carb is significantly larger then stock. So it requires air boot modifications and moving the air box forward. My write shows how I used a custom built adapter to minimize both of these issues.
Posted by: Ruby Soho
quote:
Originally posted by zrpilot
The 450R carb is shorter then the stock carb and the intake and airside of the carb is significantly larger then stock. So it requires air boot modifications and moving the air box forward. My write shows how I used a custom built adapter to minimize both of these issues.
well see, i knew that its shorter and such, but i didnt understand what your adapter was.. or what it did
Posted by: zrpilot
Just to be clear, my adapter simply lengthened the carb and stepped down the airbox side of the carb for making the airboot fit easier.
So I did not have to move the airbox from its stock mounting location. Also I did not have to heat up the airbox boot to get it to fit.
Posted by: Ruby Soho
ohhh, i understand now.
Posted by: dariusld
quote:
Originally posted by Ruby Soho
on the 450r install, do you have to modify the boot that goes from the engine to the carb?
I read you shouldn't or if you do, be careful not to make an air leak.
Posted by: FoxHondaRider
I have a few questions.
1)The stock airbox and boot should work with the 450r carb right?
2)How hard is it to install?
3)I heard jetting is difficult, anyone have problems?
4)Is it worth the $100 even with just an HMF slip on, and K&N?
Posted by: zrpilot
quote:
Originally posted by FoxHondaRider
I have a few questions.
1)The stock airbox and boot should work with the 450r carb right?
Yes, but they will need to modified slightly
quote:
Originally posted by FoxHondaRider
2)How hard is it to install?
Not really, see my Write-up
quote:
Originally posted by FoxHondaRider
3)I heard jetting is difficult, anyone have problems?
NO!
There is a lot of help, many people are running them. Plus there is a HUGE sticky devoted just to jetting the 450R carb!!!
quote:
Originally posted by FoxHondaRider
4)Is it worth the $100 even with just an HMF slip on, and K&N?
Yes, go for it!
Posted by: FoxHondaRider
wow thanks for the quick reply and answering all my questions. awesome i'm looking for a carb right now.
Posted by: flauge
No, jetting is'nt hard at all. Just remember to get your pilot set right then work your way from there.
Posted by: lorenjr83
I received my 450r carb today. i tore it down to make sure everything was clean and check the jets. It has a 50 pilot and a 155RD main. I have never seen an RD stamped on a jet. what is the RD for. is it a different brand jet?
Posted by: dariusld
quote:
Originally posted by lorenjr83
I received my 450r carb today. i tore it down to make sure everything was clean and check the jets. It has a 50 pilot and a 155RD main. I have never seen an RD stamped on a jet. what is the RD for. is it a different brand jet?
1 minute and google came up with this. "RD jets are made by RD Precision. It's an aftermarket jet that is a copy-cat of Keihin. AFAIK they use the same scale as Keihin--they're suppose to be direct copies."
Posted by: lorenjr83
what would you guys recommend for jetting on a 440 with full exhaust and no air box lid with a k&n filter.
Posted by: boosted3g
For you guys looking to do the swap get yourself one of zrpilots adapters. It will look totally stock, like honda designed a 42mm carb to on there. I got one and it only took maybe 3 hours from start to finish. I fired it up on the first try and havent touched a thing. I thought it was a little big but its not, it will have awesome throttle response and this is on a stock bore engine.
Posted by: flauge
How is it with that 52 pilot boosted3g?? Im on 3 turns with my 50 now and its borderline lean with the few mods I've got.. I'm gonna get an HMF pipe soon so I think the 52 will probably be needed then..
Posted by: dick-84
Where can u buy the zrpilots adapters?
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