Air mixture screw o-rings?

davmo · 650Rider Supporter Joined: Aug 21, 2006 Posts: 27

This my first post, although I have been hanging around about every day for months . On to my problem. I have a 79 standard with stock carbs , uni-pods and shorty reverse tip megaphone mufflers from Mikes. I have been fighting a problem with my idle for about a month. For lack of better terms, I have the pops and farts that I have heard described on here. This what I have done so far . Rebuilt carbs (also cleaned). tried 1 size bigger pilot jets, played with air mixture screw and problem got worse. I get 1 side running decent the problem moves to other side(like it is possesed). Today I removed the mixture screws and both o-rings are broken and one just broke into pieces. Is this my problem? Where can I find these? Thanks, you guys are great! David Confused

Xumi · Posted: June 20, 2007, 6:24 pm Post subject: Re: Air mixture screw o-rings?

Hi and welcome!

Well - those O-rings would definitely contribute to your problem... Not sure where you could source those. Hopefully someone else will.

In general, you will need to look at your main jets. Typically, the best course for tuning this beast is to get your mains correct first, then needle, then pilots. There's a pretty good chance that you will need to increase your mains to fix the popping.

Also make sure your slides are moving freely and that you don't have any holes in your diaphragms.

Xumi · Posted: June 20, 2007, 6:25 pm Post subject: Re: Air mixture screw o-rings?

And one more thing.. check your floats - if your floats are off, you could be starving for gas.

jimdi · 650Rider Supporter Joined: Oct 27, 2005 Posts: 512

Ok correct me if I am wrong - but if you change the pipes or put on pods (non stock) you must re-jet the carb.

xsjohn · Posted: June 27, 2007, 3:59 pm Post subject: Re: Air mixture screw o-rings?

If temperatures rise.........

John

Xumi · Posted: June 27, 2007, 6:31 pm Post subject: Re: Air mixture screw o-rings?

If you change the intake you will definitely have to rejet. If you change the exhaust... you might get away with a turn out on the screw, you might not. Depends on the exhaust, your carbs, your engine, the phase of the moon...

davmo · 650Rider Supporter Joined: Aug 21, 2006 Posts: 27

Just tought I would reply back . I found that I had new air screws with o-rings in a carb rebuild kit I had sitting around. Old age does some weird things to the memory bank. I should have time this week end to mess with the old girl again and will report back. Thanks, David

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