warrior carb tuning problem

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warriormike

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columbus, oh
ok guys im having some trouble tuning the carb on my warrior. i just finished a very mild build. when i got the quad it had a uni airfilter and a supertrapp silencer and had a 42.5(stock) pilot jet and a 150 main jet in it,it ran good i just wanted more so i recently installed a je 12.1 piston kibble white springs and retainers, megacycle 252x2 cam, mild p&p, i put in a 45 pilot and a 155 main in it and it is on the third clip on the needle and a/f screw 2.5 turns out, the problem is the thing idles great but, when you rev it in nuetral you have to feather it to midrange or it bogs, once it hits midrange it will rev great and when riding it, it bogs midrange then accells to the top end. initially i though i was rich because of the bog and no sputters or backfires on accell or decel and my plug is black. i just swapped the 155 main to a 150(i didnt have a 152.5) it does the same thing but when it makes it to top end it doesnt have to power it did with the 155. so i think im going to put the 155 back in and mess with the pilot. am i on the right track? any one got any hints? ive tuned tons of motorcycle and other atv carbs with no issues just none with the accel pump. by the way i live in columbus ohio (dont know the elevation here) and im running 110 octane cam2. i tried to be as descriptive as possible. any help would be greatly appriciated!
 
ok so i have ruled out the carb. i switched out carbs and it runs the best with stock jetting pilot and main. the plug still shows black. does anyone have any ideas? before the build the bike was weak. it ran well, idled well and never bogged or backfired just lacked power compared to other filter,pipe,jetted warriors ive ridden, im starting to wonder if my cdi is cutting out. if the spark cuts out via the cdi or the coil there will be unburnt fuel thus showing rich on the plug, right? ANY help would be appritiated, the bike is down and riding season is coming to its end and ive had to ride my scrambler wich is just nowhere near as fun!!
 
Stick with the 45/155 set up, the bog your feeling is due to a rich/lean condition caused by the needle, move the clip on the needle down a notch and try that.
 
so your saying that when i blipp the throttle or hammer on it its lean and thats the bog? when i do attempt to ride it i can hold the throttle wide open and it will just bog and not even raise in rpms, then it will come to life. but i will deff give it a shot. from what ive read around here you deff know more than me on how to tune a carb. how is that fcr on your 350 doing? i saw the burnout video, mighty impressive. did u overcome that low end bog u and gen1pat were talking about? oh and by the way the advise is greatly appriciated im at whits end with this dam thing
 
ok dune, heres the results, i switched the jetting back to the 45/155 jetting and moving the needle to the 4th position. it runs like crap. if i hold it at what im guessing to be 4000rpms it pops and doesnt run smooth. so ive come up with this, i need to find out if the cam2 110 octane im using is leaded, and i think im gonna try unleaded 100 and see what happens then, i had a buddy that had a turbo civic and during tunning 110 cam2 was tried and had to cut fuel 12% to get the thing to run decent when it ran great on 100octane. so im wondering if fuel is part of my issue. you think im on the right path? ever mess around with race gas?
 
You can try that, but on the needle adjustments if you go down a notch and it gets worse, go up!

Ive got 95% of the bog fixed, got a tad more to adjust and im done tuning it.
 
ive tried it on each notch and the best it got was on stock jetting and clip in top position(leanest one). this just has me stumped so thats why im leaning towards a fuel issue. we'll see tomorrow when i grab some different fuel
 
Personally if I was running 12:1 piston (which I am) I would cut the race gas and run e85. It's much cheaper, burns clean, and produces more power. You will need to go up around 30 percent on jetting.

My findings when tuning a carb.
First thing I do is set the pilot jet, in the float bowl (or air jet in the air horn of the carb, filter end) and fuel screw. Turn up the idle to about 2000-2500 rpm using the idle screw. Now what you want to do is listen as the bike is warming up and when turning the fuel screw. In is leaner, out is richer.
As you start to get to the perfect mixture with the fuel screw the bike will achive the highest rpm's and engine will run smooth.

Lean- poping out of the carb, sneezing. When decceleration with the throttle fully closed the bike will pop and backfire out of the exhaust.
Rich- you will hear as you turn the fuel screw out and you go past that perfect sweet spot you start to hear small back fires or misses out of the exhaust.

If you are more then 3 and 1/2 turns out on the fuel screw and rpm is still rising and engine still hasn't hit that sweet spot then you have to either go bigger on the pilot or smaller on the air jet.

After you get this circuit set which is only off throttle postions not rpm's 0-1/4 throttle move onto the main jet.

Tunning the main, 3/4 and up throttle position. Easiest way I've found. Start large or rich and work your way lean. Tune by running the bike down the road and use like 4th or 5th gear that way you can hear and engine doesn't have to labor to get wound out in rpms.
When the main jet is rich you will find that it almost acts like a rev limiter. As the ignition will not be able to burn this rich of a mixture. The more richer you are on the main the lower this rev limiter will feel like in the RPM's. As you work leaner on the main the engine will rev higher and higher in the RPM's and you will be able to feel the engine pull alot harder as you get closer to the correct a/f ratio the engine likes.

What I have found perfect jetting and most power is when the engine will rev all the way to the top of is rpm and not miss or studder "rev limiter" one size smaller on the main after you find you have just a touch on the very top end.

Next is the needle. The main jet a some carbs plays a huge roll in needle mixture. If you do not have the main set correctly then you will be off on the needle and it will make the engine not run correctly.

Work your way from rich to lean again. Start your run on the road using a gear less. Come off the top of 5th gear rpm full throttle and back it down to about 1/2 to 3/4 throttle quickly. If the engine holds speed and runs clean you are perfect. If the engine studders or acts like a rev limter you are to rich.

Hope this helps.
 
To add to Jason's post, if the throttle response is a bit sluggish at rpm, this is normally caused by the needle being lean or the accelerator pump isn't working properly
 
jason, thanks for the detailed info. i put 97 in it and im still having the same problem. ive got my pilot great with a 47.5 and 3 turns out on the air screw. the problem is when idling and i stab the throttle to wot it will bog and die. when i try the high gear pulls it does the "rev limiter" felling at what i would guess to be 4500rpms and then will acell but bogs bad before accell but after the bog and pulls great. best pull ive had was with stock jetting and it still did it just at higher rpm. i got a lil irritated and pulled the top end off and found the raised section of my piston is black like the plug which i assume to be rich but the edges of the piston ( top above rings) is burnt white which i assume meant lean. so i got my hands on a few extra parts, swapped out carbs, problem still there. im gonna toss the stock piston in and see if that fixes it. i also have a stage 1 hotcam im gonna swap out. if its none of those i guess i might have got out of hand when i ported the head and fucked it up, but im gonna eliminate fuel,piston and valve train one by one.
 
i was thinking jetting too but when i got the quad it was piped with a filter running a 42.5/150 jetting and didnt have the issue it has now. and now even with stock jetting 42.5/145 its still rich.
 
well guys after months of rebuilding my scrambler 400 and working on a diesel dakota project i made a promised to myself i would get the warrior running right before spring, so i wound up ordering a raptor 350 carb and putting that on after installing a 160 main jet and a 25 pilot i fired her up and WOW!! she runs great. the down low torque of the 12.1 piston with the megacycle cam is mighty impressive (compared to stock) and the top end hp just never quits pulling!! i would deff rec. this combo!!!
 
So the stock Rappy carb bolts right on correct? bc I am looking at one and was wondering if it is a superior carb to the warrior on re/built engines? I too am going to at least have to rebuild and rejet stock one and wondering if its worth the extra benjamin to spring for the rappy carb...
 
Also why the HUGE opinion differences in Tusk clutches? Is it simply that everyone enjoys paying for names or what? Seems to me if they were so inferior they shouldn't be allowed to manufacture them. Plus a few on here swear by them!? I plan to install a set tommorow+1 steel and HD springs to see how they hold up to my trail riding for myself before rebuilding my top end so I can change out if need be before rebuild. I just don't understand where one certain companys clutch fiber could be much different than anothers. I am sure I am wrong here but I was told years ago "Clutch fiber is clutch fiber" - HS Automotive teacher. Well, will find out for myself on sunday. Are there any new clutch wear in tricks or secrets to longevity that I should know before proceding?
 
soak the fiber discs in new wet clutch approved oil ( oil you are gonna use in the motor) over night before installation
 
So the stock Rappy carb bolts right on correct? bc I am looking at one and was wondering if it is a superior carb to the warrior on re/built engines? I too am going to at least have to rebuild and rejet stock one and wondering if its worth the extra benjamin to spring for the rappy carb...

No, you have to get the intake manifold from the rappy, too.


soak the fiber discs in new wet clutch approved oil ( oil you are gonna use in the motor) over night before installation


This is usually the case^. But, read the instructions, if there are any. SOME mfgs reccomend NOT soaking the fibers. Most do, though.
 
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