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TrailRacer4

TrailRacer4

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what's up guys this might be a noob kind of question but how do I jet my warrior? I just ordered a HMF performance series exhaust last night with the jets and uni air filter. Is it hard to do? Can I do it myself or should I give it to someone that knows what there doing? Any help would be great. Thanks.
 
You can do it your self it's very simple and there are a lot of threads on this exact question just search it and ur garanteed to find your answer


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I just put a HMF on mine about 2 months ago and ran into just about every issue I think you could possibly have. If you need any help just ask. These guys here are great about helping out or just pm me, I'd be happy to answer any questions you may have.
 
I would get mine tuned in and running great. I'd ride it that day and put it up and come back to it a day or 2 later and it wouldn't run for ****. I'd tune again and get it going and come back to it a few days later and it'd run like ****. Did this 4 or 5 times before I figured it out, and by figuring it out I mean my header pipe fell off. Fixed that and went with a 47.5 pilot and 150 main and it ran great. Switched to a Uni pod style filter and it was way to rich. With the Uni I had to use a 42 pilot and 145 main. So I went back to a K&N filter, air box lid mod, and the 47.5 and 150 with the fuel screw turned out from closed .75 turns and the needle clip down one slot and it runs awesome. I had forgot that I had sprayed wd 40 rust penetrant on the header nuts to free them up so I could change the exhaust gasket and well, that **** works great. The nuts freed up and backed off a little every time I rode it till the header fell down. Anyway I had tried every jet combo I could think of to get it to run right, I mean I screwed with it for about a week and a half before I "figured out" what was wrong. My neighbor has a stock warrior with a white bros e series pipe and I got his to purr in about 2 hours, completely different jets than I am running. I would highly suggest using the spring from a clicker pen on the accelerator pump, It makes a noticeable difference.
 
That's sucks man but at least you got it running great now. I still just don't get like what the whole 47.5 pilot or 145 main means? I should be able to figure it out though lol. Thanks for all the help guys!
 
Read up on jetting basics anywhere on the internet. Google it. Jets are a very important part of any carburetor basics.
 
Is the exhaust the only mod? I'd prolly go up 1 size on the main jet and leave the pilot alone. Pull the carb off turn up side down remove to 4 bowl screws. Pull the bowl off yyou'll see the main jet in the center unscrew it with a flat head. Check what size it is. should be 145 I beleive. Go next size up which think is 150. Turn you air fuel screw all the way in til lightly seated count the turns just for reference. Un screw 1.5 turns install carb run it if you get back fires it's lean if it bogs it's rich. Screw it in to lean and out more to richen.
 
i believe hmf recommends a 152 with just the slip on. it will be slightly different based on ur location. the uni is going to set you leaner. theres a lot of guys who run this exact same setup.

these are all Sticky threads from the instructional section. a great place to start with these bikes.

http://www.yfm350.com/forums/showthread.php?t=21231&highlight=jetting

http://www.yfm350.com/forums/showthread.php?t=15050

http://www.yfm350.com/forums/showthread.php?t=21877

http://www.yfm350.com/forums/showthread.php?t=15036
 
Maybe mine was the exception to the rule,( I have a HMF performance pipe) but using a 2 stage uni pod filter cut the air flow down enough on mine that I had to revert back to factory jetting to get it to even run right and produce a chocolate colored plug. And that was after I straightened out the loose header issue. The uni filter I used measured 3.5 x 6 inches. I even tried removing the outer layer of foam and it still preferred stock jets. I switched back to using the air box with a K&N filter and now am running a 47.5 and 150 and needle clip down 1 slot and get a chocolate plug when doing a plug chop. Maybe I was using the wrong uni filter, it slid over the back of the carb and tightened down with a clamp. I don't know but my experience with a uni wasn't pleasant. I see lots of guys on here run that set up and love it so maybe it was just my bad luck. I hope you have better luck with it than I did.
 
I asked guys that were running the uni about how they were set up and tried all of them and couldn't make it work. It whooped my ass for about week and a half and now that I got it running good, I aint touching it. Btw, my warrior is bored .040 and the rest is stock other than the HMF.
 
I also have the hmf and uni. I'm running stock jets right now and it runs like ****
 
Yea I beleive higher elevation requires less fuel because the airs thinner. Also temp effects it.
 
I mostly ride in trails and open pits? And what is the pen spring mod? Will that give me some more power?
 
Take the float bowl off your carb. Remove the accelerator pump and there is a little spring under it. Replace that spring with a spring from a clicker ink pen. The replacement spring is a little longer and a little stronger. It pushes the acc pump up higher making it move farther when you hit the throttle which in turn shoots more gas into the carb body. I just recently was told about taking the plastic side cover, not the round one but the long one, off and placing a valve stem cap over the top of the acc pump plunger. That takes up the extra space between the shaft and the part that pushes it down. This is suppose to eliminate that slight bog when you hit the gas. I did the spring swap, haven't tried the valve stem cap yet and I have no bog or hesitation when I gas mine. Hope that explains it. Also make sure you clean the acc pump and the hole it slides in thoroughly before reassembly. When I took mine apart my acc pump was stuck down and a bitch to get out. Before reassembly, take some carb cleaner, fill the bowl half way, insert the acc pump and push it up and down a few times to help clear out the fuel passage and this will show you just how much fuel is pumped when you hit the gas initially.
 
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