cuts out high rpm

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cplefka

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i have a 1996 warrior that i bought with a locked up motor.n 1 rebuilt the motor . bored .020 over, new valves{and grinded valves also}, fmf pipe and 38mm keihin carb.my problem is when you hit anything past quarter throttle it cuts out like a rev limiter.if you hold wot it bogs in and out like a speed limiter on a car. i have already grounded reverse lever, disconnected clutch switch, replaced stator an cdi. also my plug is really black and sooty through all plug chop positions execpt closed to quarter throttle. i think i have too big of a main jet. istarted with keihin 165 and down to a 145 and it still cuts out.the lowest is 100. am i going way too low with my main jet?sould i try a 100 or 120?i dont have a stock carb to compare.ever hear of valve float?
 

ratchracing

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Sounds like its running rich, but I wouldn't have went from a 165 to a 145, it could be lean now. Best thing to do with jetting is to do small steps, like a 165 - 160. Always write down what you do somewhere so you have a reference point. If its running shitty all the way past 1/4 that means you will have to change the needle position as well, same thing, go in small steps. Another thing to check would be that the float is setup correctly. Make sure the valves are in adjustment. Try some of that and let us know what happens.
 

jstcriusen1

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I would think if ya went down that much on the main and the results are identical. You have somthin else going on there.............

If your pretty sure its the carb, check the vent hoses or hose . Make sure its breathing into the bowl.

I've seen plugged vent lines do wierd things like that.

Also like ratch said, check the float. If your unsure how.
Remove the bowl, let it all hang and pick a good spot to measure it at at the lowest point of the float.

Adjust it to upwards towards carb.

Give it a shot if your unsure.............ya can always put it back.
 

cplefka

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:pi tried different positions with the float, no change.i did gradually go down from 165 to 145- 165,162,160,158,155,152.150,148,145,all rich and still cutting out.i ordered jets 140-100-will be in soon. all vents areflowing,the carb is very clean.i have no air leaks, new intake tubes, i may be chasing the wrong thing, but the only other thing left is the cam. i dont know what kind but i think it is aftermarket hi-perf. my timing doesnt line up, it is half off a tooth to the left on the cam. i tried to the right one tooth-low compression. to the left one tooth and valves hit. right now i have 135psi. i heard people talk about valves hanging open on hirpm, my valve lash is within spec. maybe stiffer springs or i need an oem cam. not much left but carb and cam, i have run without exhaust-same, maybe im going in the wrong direction,
thanks for the advice so far
clint
 

cplefka

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i dont know for sure what kind of cam it is.-or valve springs.is there a way to tell?all it says is that it was made in california. i am guessing that its not stock from what other people say about timing being half a tooth off. i bought the quad with the engine in a box torn apart. i got no info from the guy i bought it from. will cam or weak valve springs cause cutting out?the thing starts fine and idles great. its after quarter throttle it acts up if the throttle is held more that about two seconds. it got better with the 145 main ,doesnt cut out so severe, but iam wondering if i am just comensating for another problem. with the 145 the plug is still black a s hell.i should probably go on ebay a buy a stock carb and cam, but i have already wasted a lot of money on other stuff that didnt help the problem. from what info i could find on a keihin 38mm, then add says pre jetted to work with a stock motor.
 

cplefka

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i fixed my cutting out problem. i didnt go far enough down with the jets 132 was my magic number. i went from a 165 to a 132. my plug is still black, but it runs good now. any smaller jet and the plug is lean when i do a wot plug chop. is some soot on the plug alright? maybe a 38mm carb is way too big for a motor only bored .020 over. i am thinking maybe a different size needle or just get a 366 big bore to run a little faster. thanks for all the advise.
 

baja226sport

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I had the exact problem with mine and ended up using a 160 main jet and it runs excellent now.
 

boxhead

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Every motor will require a different fuel/air ratio, basically stating that a carb can't possibly be pre jetted for you. Is the noise you hear from the motor like a 'gargle'? That would be your valves floating. If not that, it would most likely be your electrical/ignition. What type of cdi do you have exactly?
 

02yfm350

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dude, this is happening to me. my quad is all stock and when I would be in a gear for example 3rd, and if i just shifted to it, and its just purring, I would open the throttle all the way and it will not give anypower for a second then it will cut power in and out like twice then it will start to gain speed. Every time it happends i go WTF it shouldnt do that. what should i do, and keep in mind that my motor is all stock, no performance muffler either. help me out!! LOL
 

02yfm350

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to add to that ^ when its revving high say in 2nd and ill let off for a bit then give it all the way it will gain speed right away but then it revvs high. but it wont gain speed right away when the motor is just purring.
 

yamarider

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Your accelerator probably isn't working properly. Check and see if the pump squirts a stream of gas when you open the throttle.
 

baja226sport

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Yeah, listen to yamarider! That was one of my problems as well. I forgot about that. The spring got all bound up for my accelerator pump and it had to be replaced. No big deal if that is the problem. You can use the spring from a pen.
 

cplefka

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i got my warrior to run good now with the 132 main jet. the problem now is it is kind of slow. i read on the site that deathshadow has tried all kinds of carbs. i have the 38mm keihin, which i heard is crappy,so will this make have no power- have to really goose it to do a wheelie and i raced it against my blaster and the blaster kept up with it . this is the only thing i have compare it to, dont know anybody else with a warrior. maybe i should buy a stock carb.
 

yamarider

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Stock warriors aren't much quicker than a stock blaster, and they're not really a good wheelie machine either with the front end being so heavy. It sounds like you just have a typical warrior to me, although you may have lost a little bit of oomph because of the bigger carb.

And don't get a stock carb, stock carbs are trash. I had nothing but problems with mine. If you're going to get a different carb, the edelbrock is the only choice that really makes sense.
 

Yamaha350rider450

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Guys I have a 1998 Yamaha warrior 350 with a k and n air filter with a zoom zoom carb and a DG v2 pipe it’s running a 150 jet in it and it cuts out when you have it at about 1/2 throttle it runs fine in 1st gear and in 2-5 it cuts out and loses all power for a split second and the it gains full power again. I have tried adjusting the float needle and all of the electrical switches I have also switched out spark plugs. What do you guys suggest I try
 
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