no pwerband, cutting/ stalling!!!

[nickpipes]

so my buddy got an 04 blaster with a 240 big bore kit, a hugee Keihin PWM carb with a 170 jet, v forve reeds and a fmf pipe, and a bunch of other crap that doesnt pertain to engine. it idles and runs fine in low rpm's but once you try to lay into it, it just sputters and looses power, if you keep it pinned for a lil bit it does kinda clear up, but still has NO power, and deff. no powerband, just a little top end once the sputtering clears up. and openions on what it is?
btw, reeds look ok, freash plug, but the piston does have a lil play

 

[Surfrjag]

piston has play? that cant be good... as far as the cutting and stalling it sounds like its not getting fuel. have him check the float height and clean all the jets out really well then do a plug chop.

 

[nickpipes]

yeah i think when he pins it, it just drains the bowl faster than it can refil itself
ima pull the carb off tommarow and adjust that float, and yeah, he ant got too many rides left wit that piston! lol

 

[acezeesawtooth]

also that pipe is a low end pipe. and you have a carb that is for top end. these things must all work together.

 

[Surfrjag]

check the petcock strainer inside the tank to be sure its not clogged also...

 

[nickpipes]

check the petcock strainer inside the tank to be sure its not clogged also...

i checked that today, it flows gas from the tank like all hell

 

[Paulie B]

No way he's draining the bowl, look for something else thats causing this.

 

[loh61546]

I recently had the same symptoms with my blasty. We checked petcock, floats, cleaned carb, checked reeds, about everything we could think of. Then I check the stator with a multimeter, found the problem, one of the coils were shot. Meaning the no power issue and sputtering was timing related. so you might wanna throw a tester on those leads from the stator.

 

[super noober]

that 170 is sure a big ass jet to have in there, what does the plug look like?

 

[99LRDblaster]

First off, you need to be more specific on what it's doing.

Is it cutting out/stalling(literally?) or is it sputtering as you stated as well. Both are opposites of each other in fuel mixtures.

Sputtering is an example of being too rich(usually on mains, but not always) and cutting, misfiring, backfiring, overheating is a sign of running too lean. What size carb is it? Is it doing this at 1/4, 1/2, 3/4-full throttle? If you are not familiar with the sputtering that occurs, then ride around with the choke half out and if it's rich it will simply sputter more, if it's lean it might run a little better. Keep in mind that the pilot/air screw controls air fuel mixtures from idle to 1/4 throttle, needle taper and needle clip position from 1/4 to a little over 1/2 throttle, and the main controls everything(in conjunction with pilot) from 3/4-full throttle.