2002 GS500, no mods (although I backed out the pilot screws a couple of years ago)
- Ran great last Oct/Nov, gave it a full tank of fresh gas w/recommended amount of Sta-Bil.

- 2wks ago and now:
Starts great, takes it's usual sweet time to get warm, once warm, however, it goes bonkers!  The idle will suddenly clim to 4-5,000rpm and stay there.

I've fiddled with the idle adj screw in hope of a temp fix to no avail.
I've also since drained the tank, added back one gal of fresh gas with a does of BG44 (trying the cheap/easy things first in hope of staving off a knock-down, drag-out afternoon with the carbs in pieces).

2 Q's for the group:
1) What could be causing this, and how would it be related to sitting for 3mos?
2) Re the idle screw - now that I've fiddled with it, what happens at each extreme, fully in and fully out?  What (# turns out) is a good starting point to get things back to normal?

Thanks.

The first thread in the FAQ section might offer some things to check.

http://gstwins.com/gsboard/index.php?topic=41199.0

Quote from: DoD#i on March 03, 2010, 06:39:08 PM
The first thread in the FAQ section might offer some things to check.

http://gstwins.com/gsboard/index.php?topic=41199.0

Thanks - have you had any experience with this after storage, specifically?

The checklist is great, but the idle screw posn was OK before storage, I'm trying to avoid a carb tear-down, etc.

 

I try to run mine every month or two when it's stored, and despite various people claiming this won't work, it has for me, thus far - so I don't have any direct experience with the problem, after storage or otherwise.

Just directing you to the stored knowledge of folks who have, or have solved, the problem, since I see it mentioned frequently enough here.

have you checked that you do not have a vacuum leak? i live in Arizona so its riding season 355 days out of the year, i have no storage specific help. However had a similar idle problem replacing the vacuum line fixed it... until my petcock dumped a tank of gas and had to be replaced .

Not yet...I'd like to avoid tearing in there if poss.  I'm hoping fresh gas will help, since that's the only thing that (theoretically) should have changed over the past 3 months. Tnks.

...all seems well again, thanks for the input.

I drained the tank as completely as possible, refilled with one gallon of fresh gas + some cleaner stuff.  It then settled into +/- normal behavior after a few 5-10min garage warm-up sessions (with lots of idle screw fiddling).  Took it out for a 35mi ride and everything was great.

I can't say if was the gas or the system cleaner stuff, but I'm glad to have at least temporarily escaped a carb job.  The carb work itself is no big deal, but the R&R process is a PITA.

Betcha one of your cables was stuck, Choke maybe, and screwing with it, etc un-froze it.

I would inspect choke cable.

Good points, both.  'Tis the season for going over all of that stuff.  Tnks.