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Main Area => General GS500 Discussion => Topic started by: vinny on April 07, 2012, 07:50:18 AM

Title: Problems Atfer Rejetting
Post by: vinny on April 07, 2012, 07:50:18 AM
97' bike, UK spec.

Decided to re-jet since i was cleaning the carbs. It now runs rough, wont accelerate unless given WOT, and dies occasionally as if its out of fuel. It also has a hanging idle, and its hard to start once warm.

Went From: 40 pilot, 122.5 main
To: 40 Pilot 125 main, 2 turns out on mixture screws.

Im going to check the throttle and choke cables and go to 3 turns out tomorrow... Any ideas what else could be wrong?..
Title: Re: Problems Atfer Rejetting
Post by: Roxtar on April 07, 2012, 08:45:49 AM
other mods? filter? exhaust?
Title: Re: Problems Atfer Rejetting
Post by: vinny on April 07, 2012, 12:21:50 PM
Air Filter = stock (And clean)
Spark Plugs = Recommended (And newish)
Exhaust = Stock-ish (Nexxus end can bodged on)

Everything else is standard.
Title: Re: Problems Atfer Rejetting
Post by: jestercinti on April 07, 2012, 05:25:22 PM
What you describe is typical lean mixture.  Kinked fuel line?  I'd do 3 turns out on the screw like you mentioned.  Out = Richer.  In = Leaner.
Title: Re: Problems Atfer Rejetting
Post by: vinny on April 10, 2012, 11:01:52 AM
Ok, i feel stupid. Part of the problems were solved by simply putting fuel in. Was so low it was running on reserve, but i had it on the ON setting. Ooops.

The hanging idle is still there, so ill lube the throttle soon.

Need to adjust the carbs too, at 2.5 turns out so far..
Title: Re: Problems Atfer Rejetting
Post by: vinny on April 12, 2012, 07:56:45 AM
At 3 turns out (roughly), and with a lubed throttle, she runs almost perfectly!
The hanging idle was still there.

Went for a 60miles hard run, with a hanging idle @4k rpm (dont do this, its difficult to ride properly), and the idle was at 4-5k.. Hmmm what have i changed recently?... jets, a/f screws, idle screw.... f***

Turned the idle screw a bit, idles perfectly at 1500rpm. Im an idiot.

For the record:
Stock air filter
Stock plugs
honda crf450x fuel tap
jets: 40 pilot / 125 main
nexxus end can bodged on
Runs great, hardly any hesitation with rolling on throttle at 60, 70, 80mph.
Sounds beautiful, no popping, no backfiring
Yay