Steve Campbell
Elite Veteran
Location: Baton Rouge, LA
| Mark,
As you know, I am very familiar with that machine. We broke the 61 LX in very carefully on the bench, and from Day One it has been exemplary.
Anytime you change something (as you did with the muffler), you will usually have to make a change somewhere else (needle settings, etc.). I have always been of the opinion that the pressure fitting on Hatori headers can have a negative impact on engine tuning. Lots of us seal that opening and re-install the fitting on the can (muffler body) somewhere.
Toby fried a plug one day when he tried Mach 7 fuel. I know, I know, everybody says Mach 7 is the same as Cool Power, but you won't convince me. I've seen too much evidence otherwise. I don't want to get into a urination competition over that (or anything else), but the only time that engine EVER burped was when we used different fuel without adjusting the mixture first. Of course, you don't know HOW to adjust the mixture until the engine "talks" to you. In this case, it ran lean and toasted a plug.
What I think you're seeing is a lean high-end coupled with a rich mid-range. Try moving that pressure fitting, then lean the low end no more than a quarter turn, and richen the high end about three clicks. Remember that you always want to get the high end right FIRST; then adjust the low end for a good idle and mid-range.
Also, keep a close eye on that aluminum gasket. They are famous for leaking. An exhaust leak, even a small one, can cause the lean high-end condition you noted.
Steve |
Is there a low end needle setting on this enging and if so, where is it?
Where is it?
