High idle...

[dhgeyer]

Lots of people here in the States do things to their carburetors to make them run richer - rejet, shim the jets, and other mods that I don't pretend to understand. I've never been tempted to do this, for the simple reason that the leaner it runs, the less gas it uses. As long as it doesn't start knocking or running so hot as to do damage (unlikely with a 250), I say lean is good.

[chandlerbingfl]

Well thanks for all the input! I ride every day so this is the first anamoly I've come across. The bike sat during the day (I work noghts) and started as it normally would. Idle crept up a bit so I adjusted the idle screw and things leveled out to where it felt normal. Unfortunately when I got up to temp the idle crept back up to I'm guess 1500-2k rpm, rides normally shifting through the gears and all. Throttle adjustment appears to be ok.

I thought at first someone was screwing w/ the idle adjustment but I still think its choke related although the choke is not something I would normally use, lever action is normal..

Keep it coming - TIA
chandler

p.s. One thing I have noticed, when shutting it off I do get one pop of backfire?!?!?!

[blaine]

Your getting a backfire because the bike is revving when you shut it off.I to think it is choke related.Take it apart at the carb end and clean plunger and bore.Move choke lever to make sure plunger is operating.Fitting is 14mm.This is a common problem on suzuki models. :rawk:

[alantf]

Originally Posted by dhgeyer

I say lean is good.

Sorry, can't agree with that. Lean can do all sorts of damage, including engine running hot, & valve problems. I believe that the European model is set up as the designers designed it. The only reason yours is set up lean is because of American emission laws. Mine gives better performance, my valves need adjusting MUCH less often, & I'm still getting the same mpg as the American bikes. This is probably because I'm using less throttle in any given circumstance. :2tup:

[3-D Video]

A lean mixture will produce an overly hot combustion; not good for the engine. And, just like a rich mixture, produces less power; not good for mileage (kilometerage?).
You can smell the difference. Too lean has an acrid smell to it. To rich has a "heavy" kind of oily odor. If you adjust your carburetor by sniffing the exhaust, do that last… you may need to sit down for awhile

[blaine]

Originally Posted by alantf

Sorry, can't agree with that. Lean can do all sorts of damage, including engine running hot, & valve problems. I believe that the European model is set up as the designers designed it. The only reason yours is set up lean is because of American emission laws. Mine gives better performance, my valves need adjusting MUCH less often, & I'm still getting the same mpg as the American bikes. This is probably because I'm using less throttle in any given circumstance. :2tup:

:plus1: :plus1:

[chandlerbingfl]

Originally Posted by blaine

Your getting a backfire because the bike is revving when you shut it off.I to think it is choke related.Take it apart at the carb end and clean plunger and bore.Move choke lever to make sure plunger is operating.Fitting is 14mm.This is a common problem on suzuki models. :rawk:

I checked the choke and the plunger is operating so I know it's not a cable issue...when I pulled the plunger and started the bike still excessive rpms. I can be in 3rd and still no throttle and do ~25mph...

Could something in there be stuck or gummed up?

TIA,
chandler

[blaine]

Originally Posted by chandlerbingfl

I checked the choke and the plunger is operating so I know it's not a cable issue...when I pulled the plunger and started the bike still excessive rpms. I can be in 3rd and still no throttle and do ~25mph...

Could something in there be stuck or gummed up?

TIA,
chandler

Put some carb cleaner in the tank,SEAFOAM or BERRYMANS B12 work well.
GO for a long ride,if it helps put some in the next couple of fill ups.

[chandlerbingfl]

How does the choke work? I see the plunger thing but does it work a butterfly valve or something?

chandler

[Easy Rider]

Originally Posted by chandlerbingfl

p.s. One thing I have noticed, when shutting it off I do get one pop of backfire?!?!?!

I think THIS might be important, as well as your statement that the idle "started creeping up".

All that can also be a sign of a vacume leak. Check the boots on both sides of the carb for loose, cracked, etc. Also the vacume line going to the petcock.

I'm kind of surprised that the problem hasn't affected engine performance when riding; if it gets worse, it probably WILL. If it is a vacume leak, it can cause the engine to run hotter than normal due to the leaner mixture.