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Main Area => General GS500 Discussion => Topic started by: abronco1 on April 19, 2005, 09:29:16 PM

Title: Help, GS revs up to 3500 in warm weather!
Post by: abronco1 on April 19, 2005, 09:29:16 PM
So when I first started riding I noticed that in warmer conditions and/or when I'm in heavier traffic the revs on my bike automatically shoot up to about 3500 rpms.  This happens with the clutch FULLY pulled in I figured out if I just "touch" the friction zone that it slows back down.  This happened to me twice today (it was about 80 in MI) today, I did twis the "brass colored" knob directly underneath the gas tank which increases or decreases idle speed.  Any ideas why it sticks at 3500-4000 when it warms up or gets too warm?
Title: Help, GS revs up to 3500 in warm weather!
Post by: abronco1 on April 19, 2005, 09:31:02 PM
to avoid any confusion the revs don't "automatically" increase to 3500, BUT when the clutch is fully pulled in it gradually increases to that rev speed, takes it about 5 seconds or less to do so, and the ONLY way I know to lower the revs (constantly after each time I pull the clutch in) is to hit the friction zone....thanks again for any replies!
Title: Help, GS revs up to 3500 in warm weather!
Post by: Ry_Guy on April 19, 2005, 10:08:45 PM
I'm not all that competant on the subject, so this is just me thinking....

It happens under hot conditions. Maybe something expanded...fuel lines, intake boots...maybe the tip of the float needle got too warm/bendable and let too much fuel in.
I know that when you have a vacuum leak, the rpms hang high. Too much air gets thrown in with the fuel and it runs faster, but leaner. If it happens again you should check your plugs as soon as you can.
I don't know why you'd have a vacuum leak when it gets really hot, cause won't the rubber expand and plug up any air leaks?
I wonder if anyone has ever had "vapor lock" before on the GS...
Again, me just thinking. Sorry I can't give you any concrete answers.
Title: Help, GS revs up to 3500 in warm weather!
Post by: JCH on April 19, 2005, 10:17:11 PM
Its running lean.  ;)   I've had enough issues (including that one) to know that.   Srinath will probably be along with how to fix it (probably turning the air intake screw (?) a turn or so...
Title: 40"s
Post by: The Buddha on April 19, 2005, 11:13:58 PM
Yea mix screw out 1/2 turn, and/or 40 pilots ... When you have it apart 125 mains and 1 #4 under needle if you're all stock.
Cool.
Srinath.
Title: Help, GS revs up to 3500 in warm weather!
Post by: Larry on April 20, 2005, 07:00:31 PM
Srinath, I just posted a question on the same issue.  Sorry I should have looked first.

Question, can I get the brass cover off of the air mix screw without removing the carbs?  What is the best method?
Title: Nope
Post by: The Buddha on April 20, 2005, 11:03:46 PM
Brass caps on the air screws will ahve to be drilled out preferably with a left handed drill bit ... make sure you dont drill into that air screw also ... and no way to get it wiht carbs on the bike. But once its off, adjustments are easy wiht carbs on bike, and replace float bowl phillips heads with allen heads and you can take off the floats too with carbs on the bike ...
Cool.
Srinath.