The cold will affect it but it would still at lease run.



toss in some fresh fuel and I would take the carb apart and clean it just to make sure.



If you wanna switch carbs, there are quite a few choices. VM26, PWK, TM, PE28's.

 

It does run.......kind of. It won't sit there and idle on it's own. It revs fair in midrange. I didn't run it out on top since it is running so flakey. It has mad popping on decell. I know an exhaust leak will make it backfire on decell. I haven't ruled that out yet.



Where should the air/fuel screw be set at? 1 1/2 turns open?

 

It does run.......kind of. It won't sit there and idle on it's own. It revs fair in midrange. I didn't run it out on top since it is running so flakey. It has mad popping on decell. I know an exhaust leak will make it backfire on decell. I haven't ruled that out yet.



Where should the air/fuel screw be set at? 1 1/2 turns open?

1 1/2 turns is a good place to start, but honestly I would clean your carb first before anything.

 

mine backfired like hell when i got it and popped on top, but down low it seemed to be ok. My problem was my ignition was bad, and my motor was brand new from the factory.

 

mine backfired like hell when i got it and popped on top, but down low it seemed to be ok. My problem was my ignition was bad, and my motor was brand new from the factory.

Hmmm. That's good to know. How did it start? Mine seems to start fine.

 

yeah it would start and run fine, didn't idle, and seemed to run fine if you were going slow then once you stared to get on it, it popped like crazy.

 

hey rlm996 what did you buy? I have a 26mm MOLKT I got from firepower if you need a carb to try......or I would sell my real VM26 for a good price if you are interested. Where abouts are you located?

 

Might sound stupid but make sure the exhaust studs are tight at the head.

 

hey rlm996 what did you buy? I have a 26mm MOLKT I got from firepower if you need a carb to try......or I would sell my real VM26 for a good price if you are interested. Where abouts are you located?

I live just north east of Elkhart Indiana about 15 min. I will mess with it a little before I decide what to do. What do you think you want for either carb? Thanks for the offer.

Might sound stupid but make sure the exhaust studs are tight at the head.

Ya, that's possible. I haven't checked that yet. Thanks.

 

on my yx150 i went with a tm 28 it runs good if you just want a cheap replacement i still have the stock carb that came with the motor.

 

mine backfired like hell when i got it and popped on top, but down low it seemed to be ok. My problem was my ignition was bad, and my motor was brand new from the factory.

From what I have been reading the ignition may be bad. Will an outer rotor from a zongshen fit? I have a new IRK that I just got for another bike from TDR. Maybe I will put that in there.

 

I've been told as well that the stock ignitions has issues so your probably on the right track.

 

anyone know about the outer rotor kits?

 

Just use that zonger rotor setup you have......you will have to use a standard type cdi unit. The cdi's for the IRKs are different ya know.

 

Ya I know. The kit has one in it. I'm pretty sure the motor I have already has an IRK in it. I haven't pulled the side cover off yet to look.

 

Ya I know. The kit has one in it. I'm pretty sure the motor I have already has an IRK in it. I haven't pulled the side cover off yet to look.

There are a couple different cdi's for the IRK's.....IFirst check to make sure the fuel and carb are good...then if still not right...start swapping the electronics........starting with a complete stock china rotor setup.

 

I think I may have found at least part of the problem.

What exhaust gaskets do these YX motors use? Are they the same as honda?

 

yeah you need to buy a exhaust gasket from TBparts, but the only way it comes i think, is in a "top end" gasket kit, Im not positive? But check it out.



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I may have missed the answer, but have you checked the pilot jet and made sure it is not clogged or partially clogged? That can cause the exact conditions you are experiencing - erratic idle, popping on decel, hesitation off the bottom, etc.

 

I took the carb off today and cleaned it. It wasn't too bad. Just a little green film on some parts. mostly on the bottom of the float and the bottom of the bowl. I removed both jets and replaced them with new. I took the main from a 100 to a 105, and the pilot from a 20 to a 25. I reset the fuel/air screw to 1.5 turns out. I also set the needle clip to the center (the needle was all the way down ie closest to the taper). I know that's a bunch of changes all at once, but I figured that's where it should be anyway. It runs better now. Not as much popping. I also installed a new exhaust gasket and new stainless acorn nuts. The plug does not show signs of being lean, but I have not yet ridden it outside (it's cooooold outside right now. like 18 degrees). I think I have it on the right track now, or atleast close. Now the only thing is that the exhaust header turns cherry red about 7 or 8 inches from the head when I'm running it. Of course it's sitting still in a garage warming up for several minutes. Maybe it won't do that so much when it's warmer. I dunno.

 

I took the carb off today and cleaned it. It wasn't too bad. Just a little green film on some parts. mostly on the bottom of the float and the bottom of the bowl. I removed both jets and replaced them with new. I took the main from a 100 to a 105, and the pilot from a 20 to a 25. I reset the fuel/air screw to 1.5 turns out. I also set the needle clip to the center (the needle was all the way down ie closest to the taper). I know that's a bunch of changes all at once, but I figured that's where it should be anyway. It runs better now. Not as much popping. I also installed a new exhaust gasket and new stainless acorn nuts. The plug does not show signs of being lean, but I have not yet ridden it outside (it's cooooold outside right now. like 18 degrees). I think I have it on the right track now, or atleast close. Now the only thing is that the exhaust header turns cherry red about 7 or 8 inches from the head when I'm running it. Of course it's sitting still in a garage warming up for several minutes. Maybe it won't do that so much when it's warmer. I dunno.

Its cherry red after a few minutes at 18 degrees....? sure sounds lean. When you pin it..does it hesitate comming off idle? if so forsure lean.

 

it's not 18 degrees in my shop. I have the heater on. But ya within a minute I would say at a high idle it's glowing red.

 

is it dark in your shop when you noticed or no? Pipes will glow but not usually that fast and only if its kinda dark surroundings.

 

I noticed it when the lights were on. I had my boy turn of all the lights, and man what a show!! He thought it was cool...lol

 

Any hesitation or bog braaping it from idle?