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Old 21-10-08, 01:03 PM   #1
cat0020
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Question Erratic idle

Hello everyone,
Newly purchased a 02 SV650S off Craigslist, stock bike, little over 4900 miles on the bike, I think the bike has been sitting for a while and I just put in some fresh fuel amixed with carb. cleaner in the tank.

The engine starts well, idles well with choke. I take it out for 6 mile ride, during the ride the engine seems to surge around 4000-45000 rpm, mild durging but noticable. Once the engine is fully warmed up, I came to a stop, the engine stays at 2500 rpm without choke, then idles goes down to 1400-1600 rpm.. then it drops down to 1000-1100 rpm every few seconds and back to 1400-1600 rpm. Engine doesn't die on its own, but the irratic idle continues, even after the radiator fan kicks on.

I wonder what the problem could be? dirty fuel filter?

-fresh fuel (w/carb. cleaner) mixed with old fuel?

-carbs need a throttle sync?

-weak or leaky fuel vacuum?

Can anyone suggest what could be causing the surging at 4000-4500 rpm? or irratic idle?
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Old 21-10-08, 06:10 PM   #2
BILLY
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Default Re: Irratic idle

Possibly a stuck choke plunger!! or your choke cable stuck at the joint under the tank!
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Old 21-10-08, 06:21 PM   #3
cat0020
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Default Re: Irratic idle

I didn't think of that one.. I'll have to check on that..

How to get the front seat off?
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Old 21-10-08, 06:30 PM   #4
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Default Re: Irratic idle

Sounds lean. Air leak or bad carb balance or idle circuit is partially blocked.
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Old 21-10-08, 06:32 PM   #5
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Default Re: Irratic idle

Quote:
Originally Posted by BILLY View Post
Possibly a stuck choke plunger!! or your choke cable stuck at the joint under the tank!
Definitely try find my thread on it it'll detail exactly what I did. Think it was 'how to remove carbs?' or 'curvy running funny' something like that.
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Old 22-10-08, 03:00 PM   #6
cat0020
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Default Re: Erratic idle

Search function seems to be disabled for me, it keeps telling me that I need to wait 15 seconds to perform the search, I try again in 30 seconds.. still the same message.

Can anyone post a direct link?
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Old 22-10-08, 06:17 PM   #7
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Default Re: Erratic idle

took some finding http://forums.sv650.org/showthread.php?t=115371&page=3

Post #22

Prepare to hinge your tank up and attack the screws on the side of the carbs to remove the choke plungers (follow the choke cable if needs be) easier to find the one on the front carb (which is less accessible) and then look on the rear one now you know what to look for, if that makes sense.
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Old 22-10-08, 06:21 PM   #8
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Default Re: Erratic idle

Front one is a right git to get to, easier to detach top of cable and remove carbs. Screws will be stuck solid. But it still doesn't sound like chokes to me.
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Old 22-10-08, 06:24 PM   #9
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Default Re: Erratic idle

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Originally Posted by yorkie_chris View Post
Front one is a right git to get to, easier to detach top of cable and remove carbs. Screws will be stuck solid. But it still doesn't sound like chokes to me.
It sounds to me like what mine was doing. Also after a quick blast then stop a the lights the revs would tick over at 2.5rpm as apose to 1.5 and on normal tick it'd jump from 1 to 1.5.
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Old 22-10-08, 06:28 PM   #10
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Default Re: Erratic idle

p.s I've got a vid of an easy way to get the screws out. Let me know if I should b rsed posting it somewhere
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