slowly dying idle...

Here is something that I've been fighting with for a while. After the engine is warm and the enrichment is turned off, my bike will want to ever so slowly start to lose RPMs until it will eventually stall.

So far I have checked and made sure valve clearances are in spec: 500 miles ago. Church of clean, replaced ALL seals: 500 miles ago. Adjusted idle fuel to best idle and synced carbs 3 times the last few weeks.

If I raise my idle, it will hang up when coming to a light, then fall to 1000-1050rpms. If I adjust idle so that it is 100-1050 rpms, it slowly starts to fall.

Bike runs great otherwise. Maybe just a little low on MPG. But that's due to my tune in the carbs.

I'm up for any suggestions...

 

Here's a quote from the preacher himself:

"A lean pilot circuit condition can be responsible for a creeping or hanging high idle, where the rpms stay high then slowly drop down to the set point."

Go have a read in the "fuel system" section of the xj4ever catalog

Are there any mods to the exhaust or intake?

Heres some more gospel:

- Fuel levels that are too low will cause a lean condition.

- Pilot fuel circuit that are partially or completely clogged.

- Fuel jets that are too small for your application.

- Pilot mixture screws being set too far "in".

Since you have gone to church I'd guess your mixture is off and your pilot screws need adjustment, or your fuel levels are lowwww

 

Would an overly rich condition do the same?

I ask because the fuel levels are on the high range within spec. I am running 41 pilot jets with close to 4 turns out on the needles. However, it won't even hold an idle with any less.

If I am lean, then it's time to invest in some smaller air jets. I don't think hitachi has 42+ size pilots.

I believe I have 205s installed right now. I may need to go back to the 195s or see if Len has them in smaller sizes.

By the way, I am running pods. Have been for the past 5+ years. It ran great in Nevada, good in New Mexico, but poor idle here in TX. Runs great above 2500rpm.

 

If it ran well in Nevada and New Mexico but it's giving you trouble in Texas, Maybe there's some water in your gas and it's gotten into some of the float bowls.

 

The altitude difference may be biting your butt.