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Air Box Mod, jetting?
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Posted by: kc8pnd

I posted this originally on predatorowners.com

'Hello all, I put a UNI filter in my stock air box and it now is starting hard, I have to unscrew the boot on the end of the carb to get it to start. Even with the boot off i have to give it just a little gas to get it to fire up when its cold, it starts great after warmed up. Another question, I cut my snorkel out an inch and a half and screwed a peace of rubber line used on a water pump and ran it the same way the stock snorkel was ran. I tried starting the quad hoping it would solve the not starting problem, it didn't, once I got it started I took a ride and smashed the throttle and it fell on its face. To much air I assume. I just ordered an HMF slip on and it comes with a bigger jet, Just wondering if it will be big enough. Would it even be the main jet causing the bogging? Or should I try changing the needle down one slot? Thanks for any advice, Mike.'
Today I moved the needle down one notch and it bogs down the same. It seems to be mid range. Maybe upping the pilot one size and trying a 165 mj? I am waiting on an HMF slipon, it comes with a 155 I think but I don't think thats going to be big enough. Ill try to get some pics of the setup if I get my camera to work. A starting point on jetting would be great, I hate to buy a bunch of jets and end up not getting the one I need.

Posted by: kc8pnd

Here is what it all looks like with the snorkel pulled out so you can see the size of the opening.

Posted by: wolffie

the trouble with a custom setup is there really is no "guidlines" for jetting. i learned that the hard way with the civic mod.

your best bet is to buy a jet kit. TRUST me it will be worth it in the long run. start with a higher mj. keep working your way up until your throttle "skips" then drop one back from that. in terms of the needle, the 4rth slot is probably ok in your setup. fiddle around with that a bit. i dont know your elevation, but im tryin to get you in the right direction. you may have to go to a 47.5 pilot, but i would leave it alone for now.

anyways, when you say "Bog" , where in relation to the throttle is it? 1/4, 1/2, 3/4 or full. from your description it sounds a bit lean.

mess with the main for a bit and then go from there. also get a +1 hotter plug. the NGK plug that the preds use is DCPR8E i believe. just go to an auto parts store give them that number and ask for one stage hotter. it should be around 2 bucks a plug. i have found those stock pred plugs are a bit fickle and tend to foul easy. thats just me though.

Now you are probably going to be foolin with this alot. unfortunately, alot of the bolts and miscelaneous parts on the preds carb are piles of ****! here are some things you will want to replace :

alright, and if you havent done so already, buy some replacement float bowl screws because they strip like a biatchh! also buy some small hose clamps for your gas line that goes to the fuel petcock and the fuel line that goes to the carb. this makes life a little easier versus those crappy *** stock red clamps! damn i hate those things, lol! also, buy another hose clamp for where the carb hooks on to the engine, because that strips out as well. and last but not least, buy yourself some replacement screws for the top of the carb (the lid that when you open up reveals the needle) and add some nuts to go with them. the threads on those screws strip easy and then just "pop" out. the nut will hold em on much better.!

Posted by: kc8pnd

I hate jetting! I am no pro and its a pain pulling that carb. The quad runs fine @ idle but about 1/2 it like cuts out then WAMM the power is on, its like a huge hesitation. If you notice on my air box where it says UP there is that rubber tube thing laying there, That's the insert for the stock snorkel, I have to put that in the end of my 2 inch hose to make it run right. It seems fine with that rubber boot in there. Anyway thanks for the info, waiting on my HMF sport slip on, after that I play on getting some jets. As for screws and what not, I already know LOL I had to grind an edge on each of the bowl screws and use vice grips to get them out, I had to put new screws in the top as well. If I can't get this to work like I like to, then look out civic!

Posted by: wolffie

no problem dude. listen, i hate jetting probably as much as you do!lol, but you gotta learn sometime. (damn i hate that cliche)

try the 4rth slot on the needle and see how that goes. just be careful with all the little washers and what not. go on www.predatorowners.com and take a peak in my profile. i have some pics of the needle to give you an idea of the correct order of em. and then adjust the main from there.

you are probably going to need to buy a jet kit though. www.jetsrus.com sells a complete kit for the pred.

Posted by: wolffie

btw, i see in your mod list you have the Fox Floats. how do you like them compared to the stock Podium shocks?

Posted by: kc8pnd

I forgot to add that I did try the clip on the 4th notch with no change. I am just going to have to get a jet kit and start doing the dirty work, glad I have a full head of hair, I am going to need it.

Posted by: kc8pnd

With my stock shocks they never had any reservoirs, So I had very little adjustability, I wanted something cheap ($600 :\) and something I could adjust. I have I think 45 PSI in them and they bounce just a tad in a set of woops. I have never bottomed them out. I might try 40 PSI to lower the front a little more. I like them a lot, they do good on trails, they soak up roots, rocks and the occasional utility quad when they don't more lol!

Posted by: wolffie

^^those sounds pretty good. what is the biggest amount of air you have landed with them? do you think the Floats could handle 15ft of height?

i also sent you the number for the hotter plug. check your PM's

Posted by: kc8pnd

There aren't a lot of jumps where I ride, but the highest I have been is about 6 - 10. They never bottomed out with just 45 PSI and they will take up to 150 PSI. The only time I ever bottomed with these was when I jumped and could not get my ***** end down and landed on my front end on an up hill, even then the shock never hit bottom, the skid plate will hit first. I'd like to try them Float EVOs also.

Posted by: wolffie

damn those sound good. yeah i would LOVE to buy the Evols too, but they are like $1500 or somewhere around there. probably worth it though. how is the jetting goin?

Posted by: kc8pnd

Waiting on my jet ket from Jets-R-Us, They shipped yesterday, hope I get it tomorrow. Got a bigger pilot and that shorter choke mod. Can't wait for the HMF!

Posted by: wolffie

what kind of HMF did you get? they are really good quality pipes. my family and friends have been runnin their exhausts for a couple of years now. i got the Sport Series in brushed aluminum.

what did you do with the choke mod? take the choke out?

Posted by: katch26

i think it put the choke onto the side of the carb like on the new outlaws, well and every other bike.

Posted by: wolffie

^^thanks for the info. kc8pnd, do you have any pictures of this setup? i may be interested in doing this.

Posted by: katch26

screws right on to the carb

Posted by: kc8pnd

its not mounted yet, but it looks like we will need to pop the seat off to get to it, which is fine with me because I never use it.
http://www.jetsrus.com/choke_small.jpg

ordered an HMF Sport slip on, i have the stock ceramic header, it should look ~ok~

Posted by: lepred

I just coiled my stock choke up under the seat where the air box used to be and cable tied it down, never use it.

Q.? Why are you running a twin Air in your stock air box ? get rid of that bulki thing and clamp the twin air directly onto the carb. Thats all I did, bought two jets 172.5 main and a 50 pilot and did the niccycles carb mod and she runs great, a ted rich but I can live witht that.

Posted by: kc8pnd

Almost got a K&N stock replacement but after I seen the needle slide on my friends predator I said naaa, his was all scratched up. It can be really dusty here at times.

Posted by: kc8pnd

Got my jet kit today. took the carb off and popped in a 47.5 slow jet and a 165 main and it runs fine. Before it would bog down and kind of sputter. The little choke mod is nice aswell, you have to take you seat off to get to it but who cares.

Posted by: wolffie

sounds good man! just check the plug and make sure you arent lean

Posted by: kc8pnd

just got my HMF, let me tell you, for the rider its not as loud as the e-series (with plates) but man this thing has some low rumble to it, I busted a 3 gear donut and stalled it and I heard the echo and it was really low. I need to rejet it now that the HMF is flowing better then the WB E-Series, throwing in a 175 mj to start.

Posted by: wolffie

^^^that should be fine if your 165 setup is good now. HMF only reccomends one step larger on the main for jetting (ex, 150 to 155)

Posted by: katch26

that choke thing is also available through Nicolas cycle

Posted by: wolffie

^^^thanks for the info. i might be checkin into that.