Can float height affect idle?

[Incubus]

My floats are set at 25mm. I am running a Uni foam filter in the stock air box, allowing freer breathing.

Is if possible that a rich running condition, combined with the easier breathing allowed by the UNI filter, could be causing my high idle situation? And I pooibly could solve it by raising the float height a mm or so?

It runs like a scalded cat over 3,000 rpm, but I want it to idle too.

The high idle situation is worse when the engine is hot.

Patrick

[Winterhawk]

Have you tried syncing the Carbs?

[webbcraft2150]

I am running a UNI with a drilled air box and have had no problems so I doubt it is causing your high idle problem. As much as I hate say it, sounds like it is still a carb problem. I think we need to put my carbs (80's model) on your bike and see how it runs. This would pretty much eliminate the carbs as your issue. After this weekends rally, we need to to get together and try this. Neither one of us have anything to lose 'cept a little time. I could pull them off and have you pick em up and try em. Ain't no big deal to be down a little while to help a fellow XS'er.

[Incubus]

I certainly haven't ruled out carbs. It's always the carbs. When that's what it proves to be, though, I have to figure out what it is about the way I've set up these carbs that is making it do this. They are sparkling clean now, and I'm going with stock settings. The needle valves seal. The only thing I can think of is the seals around the butterfly valves, which I haven't messed with. Neither did I immerse the carbs in cleaner, though.

I have to get out my parts carbs and at least figure out where these butterfly seals are. Perhaps I can scavenge parts for a fix...

Patrick

[randy]

Patrick.

Don't waste your time swapping used seals. If you're going to change them, buy new ones. Also, Didn't see your answer to the sync question - did you sync?

Rather than rich, your symptoms are of a lean condition, check boot-to head seal, use gaskets, not RTV.

BTW, won't the idle come down when you adjust the idle stop screw?

[Incubus]

I bench synched the carbs, Randy.This has been going on forever, through two sets of carbs, and they're always been at least bench synched. I bench synched these after I pulled the carbs yesterday just to bench synch them.

And that's the weird thing. I agree that this smacks of a lean condition, but the plugs are coming out sooty. I was considering that maybe I had a lean condition, complicated by an overabundance of fuel. That would explain, in my mind anyway, why the idle revs way high right up until it won't idle anymore. Like it has too much air and fuel until you back off the throttle enough to cut off the air altogether.

I'm running out of places to look for a vacuum leak. I have new carbs boots, I have new aftermarket non-vacuum petcocks from Mikes XS, I have new vacuum line and new caps on the carb vacuum adjuster tubes. I've tried two different vacuum pumps and two different pickup coil plates, mixing and matching all the parts, with no change of condition. The only constant through all this is the top end itself and carb number four, which I had to move from the first set of carbs to the second set of carbs because of a broken float mount. I'm thinking I have to take a closer look at that carb, or maybe all four.

If it idled, it would be done - at least with anything that makes me hesitant to ride it.

[underdog57]

The shaft seals are right at the outside edges of the carb body.
I'd think you could do the wd-40 trick to see if you have leaking shaft seals ...
to remove the butterflys , I ground the swaged back end of the screws off . they are really easy to strip the slots out otherwise .

I have a lot of extra SS screws for butterfly screws .Let me know if you need them ...

On my carbs I left the little inlet screens out , might be my mistake. # 4 carbs started leaking out the airbox after my long ride today ...R they available new??, mine were in bad shape ...

Bob

[underdog57]

On the bench synch , mine were way off when I did the trans fluid home made sync tool .
When I did mine I put the tube in a loop , attached it to a yard stick . put the 3 ft of fluid in .
I did two carbs only , 1 to 2 , then 3 to 4 . To 2 to 3.
When you do the screw for 2 to 3 they move 1, 2 together and 3, 4 together . hope that makes scence .

Bob

[randy]

As I wrote to Patrick,

check boot-to-head seal, use gaskets, not RTV.

This may be where your vacuum leak is. Don't ask me how I know!


P.S. you'll have to make the gaskets, can't buy 'em!