I have recently moved to about 5000' elevation and installed a fmf pipe silencer and changed the clutch springs and rear gearing on my sons pw50. I adjusted the idle screw and air intake but it seems to chopout at full throttle wide open on the test stand. I put a 67.5 main and open the airbox up with a different filter plus 1" air box filters. I am running Motul for the oil injection. He has a race coming up in 2 weeks any ideas to clear up the topend matter would be appreciated.
pw50 setup help
- Thread starter brlatm
- Start date
Try moving the needle clip up a notch and/or leaning the main out a bit. I don't remember what the stock main is, but I think it was a 65, if so, you should probably go to a 60. If it was a 70, the you need a 65. Also, a fouled plug can make it run like crap.
There is less oxygen up there, therefore less fuel is needed. I know that the needle shouldn't affect WOT, but the PW50 is a little wierd at times. Even the mix screw can cause it to run wrong up there.
I referenced this chart for the correction factors to get proper main jet size. Athough I only estimated, and didn't take temperature into consideration.
http://www.motocross.com/motoprof/moto/mcycle/carb101/carb101.html
I referenced this chart for the correction factors to get proper main jet size. Athough I only estimated, and didn't take temperature into consideration.
http://www.motocross.com/motoprof/moto/mcycle/carb101/carb101.html
You sure it's not your rev limiter? When you put the pipe on and open the airbox it revs much quicker. When the rev limiter kicks in it becomes MUCH more noticable. It will run and then break up and if you keep holding it on, it might clear back out for a moment and then start breaking up again. I've seen a lot of people think their bikes were running terrible after they modify them, but in reality they were running stronger and the rev limiter was tricking them into thinking they were running poorly. Hope that's your case. Oh and if you're sucking air, it will definately pop!