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Main Area => General GS500 Discussion => Topic started by: dirk on December 16, 2020, 11:33:07 AM

Title: Accelaration problems
Post by: dirk on December 16, 2020, 11:33:07 AM
Hi guys, I own a GS500 from 1993. Everytime the engine reaches 8500 rpm it falls dead. Cleaned already the carburettors, changed the needles, air filter, fuel filter, .... Even changed the electronic module. Nothing seems to help. Has anybody had the same problem or an idea to solve the problem? Thanks.
Title: Re: Accelaration problems
Post by: Dipper on December 16, 2020, 09:29:23 PM
I would be checking the main jets.

What do the spark plugs look like?
Not sure what area you are riding in. Here in chicagoland I always change jets based on the season. You need bigger jets in the cold weather or you will be running lean. Try restricting the air intake with some tape and see if it gets better or worse.
Title: Re: Accelaration problems
Post by: herennow on December 16, 2020, 10:57:47 PM
I'd also check main jets, what size do you have in there? I'd suggest too big. Bikes run well when slightly lean, until they blow up. ;-)
plugs are good?
Title: Re: Accelaration problems
Post by: gruntle on December 20, 2020, 05:34:17 PM
Check brain, always worth checking brain first...
frequently wrong...
:angeldevil:
Title: Re: Accelaration problems
Post by: mr72 on December 23, 2020, 06:00:14 AM
mine did exactly this with too large main jet.
Title: Re: Accelaration problems
Post by: Meukowi on December 24, 2020, 10:04:08 AM
So did i, also wot accleration were coughing and struggling to gain speed. Changing mainjet to smaller size fixed it.
Title: Re: Accelaration problems
Post by: nurms on January 07, 2021, 03:52:46 AM
Old GS:s are the best :icon_mrgreen:  I live in northern europe so quite cold out here. My GS works perfectly (at least if you ask me  :hithead:) and I changed this setup last summer: ORIGNAL air filter (vacuum carbs so original is the best), main 127.5, idle 40, needle one groove up from middle (assuming you have same adjustable needle) and mixture screws 3 full rounds open to compensate new bigger idle jet.

works great, mine did not work at first due to hi-flo airfilter. With original, everything works great  :cheers:
Title: Re: Accelaration problems
Post by: herennow on January 08, 2021, 05:54:39 AM
where di you get original Air filter? I struggle to get them in EU?.

Thanks
Title: Re: Accelaration problems
Post by: mr72 on January 08, 2021, 07:50:12 AM
Quote from: nurms on January 07, 2021, 03:52:46 AM
Old GS:s are the best :icon_mrgreen:  I live in northern europe so quite cold out here. My GS works perfectly (at least if you ask me  :hithead:) and I changed this setup last summer: ORIGNAL air filter (vacuum carbs so original is the best), main 127.5, idle 40, needle one groove up from middle (assuming you have same adjustable needle) and mixture screws 3 full rounds open to compensate new bigger idle jet.

works great, mine did not work at first due to hi-flo airfilter. With original, everything works great  :cheers:

This may be cold weather only kind of thing.

In the summer, my GS with 127.5/40 and a UNI air filter was too rich. I think I'm back to 125 jet. Maybe 122.5 (stock). I can't remember. But 127.5 was way too much in the TX summer. It was like 95F+ every day.
Title: Re: Accelaration problems
Post by: sledge on January 08, 2021, 11:21:26 AM
Where exactly are you?

Going from your description it sounds like your bike could be restricted.