Ironhead Running rich on my front cylinder

[JBGoode]

Are you running points? My front cylinder ran forever richer on the front cylinder and I've tried everything to figure it out. I threw a new set of points in and 'centered' the cam lobe better and now they're both even stevens.

[jhaines]

Originally Posted by 2007Low

Does it run ok?

It does until the plug fouls

[jhaines]

Originally Posted by JBGoode

Are you running points? My front cylinder ran forever richer on the front cylinder and I've tried everything to figure it out. I threw a new set of points in and 'centered' the cam lobe better and now they're both even stevens.

Points are newish. I'll look at the cam.

[2007Low]

How's the compression?

[squirt]

A little while back, I noticed the same issue when I was trying to diagnose a sputtering problem in 3rd-4th, and realized that my idle circuit was way to rich. Once I resolved that issue, the rich plug condition on the front cylinder went away. Just my experience, not sure why it affected the front more than the rear.

[jhaines]

Originally Posted by 2007Low

How's the compression?

160 on both cylinders ; open throttle; HOT (icing finger tip now) engine

[jhaines]

So.... I adjusted my idle circuit, as best i could as the engine was blistering hot. I counting the gap between the rich and lean engine stalls and set it in the middle. It idled great and and I was able to turn my throttle set screw WAY down.

However....

Now the bike stalls under acceleration.
If I screw it way out (around the 2, 2 1/2) mark bike runs rich, but runs under accelaration.

Before I jump to any conclusions I want to do a more precise adjustment with a cooler engine, but I wanted to give y'all time to think

[IronMick]

Originally Posted by jhaines

So.... I adjusted my idle circuit, as best i could as the engine was blistering hot. I counting the gap between the rich and lean engine stalls and set it in the middle. It idled great and and I was able to turn my throttle set screw WAY down.

However....

Now the bike stalls under acceleration ...

Blistering hot is good for setting the idle [unless it prevents you from doing a good job of it]. You had it set correctly for idle so put it back. Next you need to install a larger slow jet to solve the acceleration problem.

[jhaines]

Originally Posted by IronMick

Blistering hot is good for setting the idle [unless it prevents you from doing a good job of it]. You had it set correctly for idle so put it back. Next you need to install a larger slow jet to solve the acceleration problem.

Understood, it was just hard to count screw turns:

1......2......3......4

[IronMick]

My experience with counting turns is that it cannot be done accurately with the carb on the bike. Once i get it running well i take the carb off the bike, put it on my carb stand, check the number of 1/4 turns [using a better sized screwdriver] and write it down. It is always different from what i had thought.

Too hot, too crowded, screwdriver too small, etc. Only accurate off the bike.