I didn't think it was too lean, its only on the base HSN setting (3.5 turns out), and smokes like a good'n. []

The only other change has been to run a ultra cool plug as this was the only way I could get the temprature down.
Could this have caused it??
Mind you, it has been stalling alot recently.

I guess I switch back to 20% as there was no damage after 1 gallon went through it and persevere.
What is the worst that could happen? Either way a new piston and sleave will be on the cards soon I guess. []