Finally got a '99 vintage Ls650.  16,000 miles, supertrapp, 16mm travel on cam chain tensioner.

I did the white spacer mod to half thickness, then noticed the darned idle mix has been exposed and stripped.  I OCCASSIONALLY backfire when advancing gears, but the plug color is acceptable over a series of throttle chops.

I don't like the backfire though.  Any suggestions on removing and replacing the strip mixture screw?

Thanks, reelthing.  No, no leaks.  Checked that very thoroughly.  Like I said, the plug looks good, I just have to get stuff perfect and so knowing that adjuster is stripped plays havoc on my brain.  I can get the screw out with an easyout no problem.  My concern was replacement.  Anyone ever removed their idle mix screw and can give me dimensions?  This is my daily driver, so I'd like to have the new screw in hand before I pull the old one.

bsdnfraje wrote on 04/19/08 at 07:20:44:


The idle mixture screw isn't just a typical machine screw, it has a needle on the end. If you need a new one you have to buy one for that particular carb, either from the dealership, or online. You could take the screw out and cut a new slot in it, just make sure that the threads are clean with no burrs as the carb is aluminum and those threads will strip out easily.

Yes you can get a pilot air screw (that's what the stealership calls it) and it is only between 2 and 5 bucks.

Awesome, I'll hit the stealership later this week then.