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Carbs for built motors
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Posted by: QuadJunkies

Just curious what kind of Carbs ya'll are using for your built 250's???

Posted by: vondeister

I tried a FCR33 with no luck
I now have a mikuni 30mm that works great!

Posted by: QuadJunkies

quote:
Originally posted by vondeister
I tried a FCR33 with no luck
I now have a mikuni 30mm that works great!

Thanks for a response! Im still blown away be how little information is out there about this quad.

What all did you have done to your motor? Has it been reliable?
Ive been curious how they are all holding up. IVe heard they actually do pretty well.

Posted by: wvspeedfreak

Vondeister,what problems did you have with the fcr33?Was it hard to tune?

Posted by: mxslevnik69

the fcr 33 carb makes the thumb trottle rediculously hard. my friend has it on his raptor.

Posted by: QuadJunkies

quote:
Originally posted by mxslevnik69
the fcr 33 carb makes the thumb trottle rediculously hard. my friend has it on his raptor.

I remember it being that way on alot of other quads also. That wont be a route we will go. I def. want a good performer but not if it creates thumb pump.

Posted by: vondeister

The FCR was a pain to tune. I could not get the off idel bog out of the FCR33. It ran good at W.O.T. but low and mid rage was bad.

The mikuni 30mm was easy to tune and made 3.8 hp increase over the stock carb that was jetted to the moon. The mikuni requites you to space up the fuel tank in the back about 10mm for cable routing, but its no big deal.

My engine is has a 12 : 1 JE piston standard bore, web cam, ported and polished head, HMF full system, Dynatech CDI, open air box with Pro design air intake and Mikuni 30mm.

this combo seems to work really well.

I hear the Rage kit is the way to go, I'm going to paint our frame this winter and get the Rage kit, it makes 34hp.

http://www.youtube.com/watch?v=9qBSFN9CMHA

Here a link of my son winning a TT race a few weeks ago; due to a jump start he had to start on the 2nd row. #6 blue raptor orange riding gear.

Posted by: QuadJunkies

Thats was a good race,he made those passes nice and clean-well done! Good info and thank you!
I think we are going to mod the stock one for now and go from there .
We have a freind who knows how to internally open up these carbs to the same size .
Is that 34HP reliable power ? We race cross country /desert so reliability is important.
My sons just coming off a CVT so I think what we have will be PLENTY for him for abit.

I dont know what all has been done to it yet, we havent ran the motor yet ,we are waiting on our frame to be shipped back to us,but I know it will require full race gas

Posted by: vondeister

so far the kid that has the Rage 300 kit hasn't had any proplems that I herd of.

thanks for the compliment on my son, he is a great rider, and we are having a blast.

good luck

Posted by: bradley300

11:1 piston, SMS head work, gytr full exhaust, SMS airbox, kibblewhite valve( exhaust i think?) and i have a FCR 28mm that works great

Posted by: sno-x139

34hp?
wtf? who told you that
i dealt with rage direct and mine was the first he ever built
he dynoed it on his dyno and got 31 and 22ftlb tourqe
he also told me that tc,hetrick and everybody claims all this power
but when he puts it on his dyno its like 28hp
he said he has never seen a 300ex over 31 or 32 he also said he
never saw one over 21ftlbs
give him a call dee is real cool to talk to
i raced a few nats and it was definatly the quickest raptor there
rageatvracing.com
i also holeshoted the c class once at a local race

Posted by: XBLASTERRACERX

Well no offense but I just had my 300ex built by TC and it is pushing out 33/34 hp and my friends built by east coast is pushing out like 35 hp so 300ex defenatly make more power then just 31 hp. Oh and another friend of my had his 300ex personally built by rage is putting out atleast 34/35 hp.

Posted by: vondeister

Dee told me 34hp over the phone and the guy that Dyno'd my sons Raptor 250, said he dyno'd a rage raptor that put out 34hp as well.

I'll let you know when I get my rage kit this fall.

Posted by: mxslevnik69

yeah my raptor has about 35 hp

Posted by: QuadJunkies

While I like dynos and feel they have alot of value, in other ways they arent so much. HP ratings varies on each dyno. Id like to make sure about good torque and getting good power to the ground where is needed with good suspension and tire selection. I seen whatg a waste power was for my son when his quad was skipping all over the place on the track.
I cant wait until we are done with ours... as long as it produces good useable power and is reliable- Im happy!

Posted by: bradley300

quote:
Originally posted by QuadJunkies
While I like dynos and feel they have alot of value, in other ways they arent so much. HP ratings varies on each dyno. Id like to make sure about good torque and getting good power to the ground where is needed with good suspension and tire selection. I seen whatg a waste power was for my son when his quad was skipping all over the place on the track.
I cant wait until we are done with ours... as long as it produces good useable power and is reliable- Im happy!

good observation! most people get real caught up in the numbers, but unless you used the same dyno for the same quad before and after, no number you say matters.

Posted by: QuadJunkies

quote:
Originally posted by bradley300
good observation! most people get real caught up in the numbers, but unless you used the same dyno for the same quad before and after, no number you say matters.

Tuning is what our main goal will be for the Dyno. for our application and for the age of my Son or ours will be more than enough power for him for awhile.

How have you been Bradley??Hows the racing going ?

Posted by: forgiven

The high horsepower numbers are great but for woods riding and mostly torque applications I wonder if those are going to help that much.

Posted by: QuadJunkies

quote:
Originally posted by forgiven
The high horsepower numbers are great but for woods riding and mostly torque applications I wonder if those are going to help that much.

Thats what is mainly needed for our appplication as well.

Posted by: mxkids

maybe this will help our raptors have max power 300 kits one with big valves one without both have custom head pipes and silencers hand built just for our motors one is a sparks pipe.the small valve motor has 29 hp on 4 different dynos . it runs a 32mm fcr off a crfr150 honda the big valve motor has 31.7 hp on 4 dynos it runs a 37mm fcr carb with a custom intake. both bikes have over 100hrs with no issues except broken clutches. we race with the tc 300 hondas and have been the only raptors that has even come close to the best hondas. i wasnt impressed with the rage motor compared to mine its close to my small valve motor. Brandon Tittle

Posted by: wvspeedfreak

How would an FCR 33 be on a stock motor with just a full exhaust system and GYTR filter?

Posted by: QuadJunkies

We have a freind locally who does alot of carb mod work who does a really good job .
We decided we are going to have him rebuild the stock one and open it up and see how it works, we couldnt pass up the price . Ill post how it does!

Posted by: wvspeedfreak

Definitely keep us posted QJ.I am curious how much can be done to the stock carb.

Posted by: QuadJunkies

quote:
Originally posted by wvspeedfreak
Definitely keep us posted QJ.I am curious how much can be done to the stock carb.

Will do. He said he should be able to get things where we want after he orders some new internals.
He just done one for a freind of mine who has a built KTM thats a member here and he is pleased so far.

Wish I had some ideas on your issue, I asked Troy and he said he wasnt sure either. Made me remember to order a service manual today.

lol

Posted by: wvspeedfreak

I put the carb back together and put it back on the quad and now it runs fine.I didn't see a thing in there but it must have had a piece of dirt in the pilot.

Posted by: QuadJunkies

quote:
Originally posted by vondeister

I now have a mikuni 30mm that works great!

Would you happen to have a part number for that carb and any pics ? That would be great! Im kinda of surprised there isnt more carbs avail. and even more surprised how little info there is on the 250 on the internet. Glad we have a few good folks out there to turn to

Jason, looks like the stock carb is a no go on getting modded. He said it wasnt worth the effort on that particular carb

We are still going to see how it performs on a Dyno and then add a carb and compare . My concern was if we would be dealing with a jetting nightmare or not .

Posted by: jakes

CT Racing have 3 carburetors available for the Raptor: Mikuni 30mm Flat Slide; Keihin 30mm(bored 28mm) FCR; Keihin 33mm FCR

Posted by: wvspeedfreak

Thanks for the update Tina.From what I have gathered the 30mm Mikuni is a great carb and alot easier to tune than the FCR.I have an FCR33 here that I was planning on using when I got motor work done to Austins but I have heard they are very tough to get right.

Posted by: QuadJunkies

Thanks for the list of whats avail. !!

So how much is the Mikuni? Does anyone else sell the Carbs besides CT? I called them last week to get some info on the carbs and was not impressed with there service, they didnt seem to want to answer some questions so they apparently dont want the sale .
Also, will it mount up to the stock intake boot? Does it mount right up? Is there really much dif. changing by that small of a carb size difference?

We had a motor builder told us the FCR wasnt the best choice on a 2 valve head ,not to mention the stiffness. Since he is only 12 yrs. old and his hands are still small . He races endurance races mainly. Not sure on the truth on that but we def. will not have any interest in that carb.

I think we just might give the Mikuni a try.

Posted by: QuadJunkies

quote:
Originally posted by vondeister
I tried a FCR33 with no luck
I now have a mikuni 30mm that works great!

Just spoke with CT and they said this carb is a PITA due to the way its routed..?? he said the stock carb will stall out in air and G-outs and is not reccomended for racing.
Can I ask you how yours is routed and if you have a picture ?? Id like to give you a call or anyone who I can talk to about all our options. He reccomended the FCR and was told its not stiff.

All the carbs he said route weird but the FCR. I just cant get myself to pay that price.

Theres got to be another place to buy these carbs...

Posted by: wvspeedfreak

Tina,I have an FCR33 that I am going to install and tinker with soon.Maybe in doing so I can give you my input on this carb.

Posted by: QuadJunkies

That would be really great jason.

Posted by: vondeister

send me a email at bdeister@motorcitysolutions.com
I can tell you about my mikuni 30mm