Mk ?

[kenjolly]

Haydens 70 runs smooth on both top and bottom but has a miss in the middle. I cant figure it out .HELP!!!!!!!!!!!!!!
i havent changed anything, only replaced stuff to try and fix the problem.

[Nichols Atvs]

I also chased a mid range sputter. We ended up replaceing crank seals that took care of our problem . I have heard of a cracked piston . and make sure spark plug gap is about .015 thousands if running NGK br9eix. I thought it was electical or carb but not the case. Good luck Ken keep us updated.

[kenjolly]

im not running that because im not running a PVL, but i will check that.

[Nichols Atvs]

Im not running a pvl either . NGK BR 9eix are spark plugs. Check the gap it should be about .015 thousanths .

[bulldogfallon]

Have you adjusted your needle clip setting or air screw?



Bring it on Sunday

[kenjolly]

I thought you only needed that plug IF your using the PVL. im using a B8es or B7es.

Thanks Gary i will try that,

[neveready]

We run the iridium plugs in all of our bikes. Great plug, no fouling. We have one in our AC 90 that has been in it since november last year with 40+ races and still runs and looks great.

[kenjolly]

problem solved, Gary said try ajusting the needle and it worked.

Thanks for the help.

[WOLFPACK]

Although these little monsters are simple in design they are sometimes complicated because ofter when there is a little miss so many different things can be the culprit.

FYI on jetting:
Pilot jet effects 0 to 1/4 throttle
Needle 1/4 to 3/4
Main does the rest
If you approach all jetting with that in mind you'll get through it faster.

We recently had a problem with a motor we built for a customer. They are 1000 miles away so we had to solve thier problem over the phone. The bike bogged out of the hole, ran like a beast when it got on the pipe and flooded when they chopped the throttle. We originally had thought that it was a rich main because it happened at full throttle. We were wrong, it happened at 0 throttle position. That info coupled with the fact that it bogged coming out of the hole had us change the pilot. We went from a 45 pilot down to a 40 and the problem was fixed.

But it could have been any number of things. You just have to hit the easy ones first.

Glad you got your problem fixed! Gary is the Man!

[Nichols Atvs]

Good to here you gotit did you go up or down