Mystery of the Bogging Throttle - Maxi

I finally got my project Maxi back together, but its not running right. It starts fine, maybe bogs a little then runs great. However, once the rpms get high enough, the throttle dies. No clue whats going on. Too rich? Too lean? Bad timing? Bad points?

I've played around with all of the variables, but it still seems to have this weird tendency to cut out at a high rpm. It almost sounds like it stops firing, but I have no idea what is the issue.

To be more specific, it revs and accelerates, but once it reaches a certain speed/rpm/throttle position (I'm not 100% on any, though I think its the rpms), the throttle stops functioning and the motor peters down to idle.

I case matched it and opened up the intake a little bit, but nothing too aggressive. K-Star with a 14mm Bing. I matched the intake port for a larger intake (I had dreams of a 17mm Bing), but I don't think thats the source.

Re: Mystery of the Bogging Throttle - Maxi

If you did all them changes.. at once.. you in a hell a bender .. now..

I would plug chop.

Did you upjet with all that porting..

Re: Mystery of the Bogging Throttle - Maxi

I had the entire engine apart, so I had no choice but to change the position of the stator plate.

I upjetted to an 88, but it seemed too rich. Dropped to an 82 with an air filter and it ran fine. Until it revs up high enough and quits.

Re: Mystery of the Bogging Throttle - Maxi

Could it be timing?

I don't think the float bowl has been filling up entirely, either. But I'm not sure.

Anyone know how to check that?

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