82 yz490 hesitating

[mkpack77]

one of my 490's that i recently built has a hesitation problem, kind of like when a plug starts to foul. i figured it must be the timing, but it's spot on....any ideas???????

[dogger315]

has a hesitation problem, kind of like when a plug starts to foul

Sounds like a lean condition. When you say hesitate, are you talking
about a "boooowah" type response when you rap the throttle? If so,
try riding the bike with the choke partially engaged to see if that helps.
If it does, richen the jets in one step increments until it clears out.

dogger

[Big Maico 393]

My first question is have you done the head mod?

If not no amount of jetting will fix your problem, it will just move it around!

Once you do the head mod,call Herb at Maico Only/Proform racing & tell him that Howard from Texas sent you!

Tell him you need a pipe, then jet the bike & hold on to your shorts!