YZ250J 82 JETTING

[Cappy]

Good Evening,

I recently rebuilt my clutch and was just putting my carb back together. Last time I had the bike together running it would not idle well. Slowly die. Well I just found out that the pilot jet was a 17.5????? Why in the world would anyone use such a lean pilot when stock is 45? The bike is on it's first rebore so .5mm over. I should have a 45 pilot in the garage somewhere. hopefully it does the trick.

Does anyone know of any jetting problems that Yamaha had with this bike?

I will be performing plug chops once I get her back together with the correct jets. 370 main - 45 pilot. 2 clip pos.

Thanks,
Greg.

[Cappy]

45 pilot installed. Starts and runs good. No more stalling. Wish I would of figured that out a year ago.

I also had a guy in the shop machine a reed spacer .25" thick. Seemed to add a little low end. How can I attached pics?

[bronc3]

Originally Posted by Cappy

How can I attached pics?

I usually host mine through Image Shack.

[Cappy]

OK,

I have now installed 45 pilot (stock pilot). Went from 370 main to 360, then to 350. Still idles well. Upon more than 3/8 throttle it won't rev out. Could I still be too rich? Have not pulled plug. Everyone tells me these bikes were jetted rich from factory. I have also installed a .25" thick reed spacer to pick up low end, it seems to work really well, but after more throttle it bogs badly. Who else has a YZ250J on this board. Any thoughts. Probably going to pick up a 340 and 330 main. Anyone need jets? This is a trail rider with a 38 year old on it. Please help. Also no airbox, Large UNI pod installed. See pic in Show me your YAMI link.

Thanks.
Greg.