Since I have some down time waiting on parts I decided to check the carb-pull the bowl off and make sure everything is clean. Everything is where I set it but I have a question on the throttle valve adjustment-the wide open setting is adjustable so that the slide can be moved up or down in the body. My question is do you adjust it so that the entry side is flush with the venturi or so that the exit side is flush? If you have it set with the entry flush then the exit protrudes a few mm into the venturi. I think that setting it so the exit is flush would be correct but I can't find any info to back it up.


Anyone know the answer???

 

This came up awhile back...can't remember who was asking it then, but I don't think there was any bottom line answer. I'd bet you'd have to do a dyno test to see if there was actually any performance difference. The Mikuni tuning materials don't even address it...at least none I've seen for the pumper series. There might be something out there somewhere. As long as you're getting a full throttle bore exposure, I think it would be surprising if the KLX would benefit from much more than that.

 

Cycle Magazine found a noticeable drop in cfm decades ago while testing a carb with a small amount of the back of the slide protruding into the air stream compared to no part of the slide running interference. Enough for them to suggest you make sure to everything is out of the way.

I adjusted my TM36 so the back of slide was just a tiny bit above the top of the bore so nothing is hanging into the air stream..