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Main Area => General GS500 Discussion => Topic started by: flambert on August 14, 2019, 04:22:09 PM

Title: Gs500E trouble cruising
Post by: flambert on August 14, 2019, 04:22:09 PM
Hey guys,

I currently have problems with my gs500e, when I try to stay at one speed after a little time it loses power, I am able to give more throttle to accelerate. If I add choke it runs better, so that tells me that it's missing fuel.
I have tried to adjust the fuel mixture screw without success, don't know if I am doing it wrong..

The carbs are clean.

If anyone could help that would be awesome:)

Ps. It's EU version with less hp (A2)

Title: Re: Gs500E trouble cruising
Post by: Bluesmudge on August 14, 2019, 04:42:08 PM
Do you have an in-line fuel filter?
Are you running the stock airbox/airfilter and exhaust?

AFAIK the mixture screw only affects the idle circuit. It won't do anything for you here
Title: Re: Gs500E trouble cruising
Post by: Watcher on August 14, 2019, 06:35:01 PM
Quote from: Bluesmudge on August 14, 2019, 04:42:08 PM
Do you have an in-line fuel filter?

If that were the issue then the choke wouldn't fix the problem.

Quote from: Bluesmudge on August 14, 2019, 04:42:08 PM
AFAIK the mixture screw only affects the idle circuit. It won't do anything for you here

I think the same.



It almost sounds like the slides are slowly falling at speed.  He can accelerate just fine so a large change in vacuum does raise them up, but holding a steady throttle loses power, so perhaps the slides are having trouble staying up.
Possible vacuum leak?
Title: Re: Gs500E trouble cruising
Post by: flambert on August 15, 2019, 02:01:13 AM
It gets enough fuel in the carbs just not in the engine, maybe I should triple check for vacuum leak? Everything is stock.

But in case it's not a vacuum leak any other suggestions?
Title: Re: Gs500E trouble cruising
Post by: flambert on August 19, 2019, 06:09:18 AM
Haven't been able to locate any leaks, any possibilities that it is something else? :)

Title: Re: Gs500E trouble cruising
Post by: herennow on August 19, 2019, 07:20:42 AM
what happens if you run it on prime?
What are float levels (clear tube method check takes 5 minutes)
Title: Re: Gs500E trouble cruising
Post by: The Buddha on August 19, 2019, 08:46:58 AM
Steady throttle problems are because of being too lean. Its called a lean surge.
You need to check what jets you have. The restriction just prevents the slide from coming up fully right.
That wont affect jetting, I don't think. But your throttle position correlation will be useless. Its effectively like you're at 1/2 throttle even when at full throttle. Anything up to 1/2 is what the actual position is, and over 1/2. its 1/2.

Either way, all stock bike 01+ right ? 20 and 132.5 is you right jet size 3 turns and 1 washer. 89-00 would be 40 and 125/3/1.

Cool.
Buddha.
Title: Re: Gs500E trouble cruising
Post by: Bluesmudge on August 20, 2019, 12:29:59 PM
Quote from: herennow on August 19, 2019, 07:20:42 AM
what happens if you run it on prime?
What are float levels (clear tube method check takes 5 minutes)

Yes, any change when running on prime or reserve?
Title: Re: Gs500E trouble cruising
Post by: flambert on August 21, 2019, 01:03:30 PM
In Germany you are not allowed to change the jets since that it's "tuning"

On prime there's no difference.

If I cruise at 70km/h after a while it will lose power, if I give more throttle it's accelerating properly.
Sometimes it backfires after losing powers.

Could it be the ignition that fails?

Title: Re: Gs500E trouble cruising
Post by: qcbaker on August 21, 2019, 01:44:21 PM
Quote from: Watcher on August 14, 2019, 06:35:01 PM
It almost sounds like the slides are slowly falling at speed.  He can accelerate just fine so a large change in vacuum does raise them up, but holding a steady throttle loses power, so perhaps the slides are having trouble staying up.
Possible vacuum leak?

I think Watcher has the right idea here.
Title: Re: Gs500E trouble cruising
Post by: flambert on August 22, 2019, 12:11:03 AM
Quote from: qcbaker on August 21, 2019, 01:44:21 PM
Quote from: Watcher on August 14, 2019, 06:35:01 PM
It almost sounds like the slides are slowly falling at speed.  He can accelerate just fine so a large change in vacuum does raise them up, but holding a steady throttle loses power, so perhaps the slides are having trouble staying up.
Possible vacuum leak?

I think Watcher has the right idea here.

I think aswell, but just haven't been able to locate any leaks, I think it might be in the membrane/throttle head.
Is there a better way to detect if there is a leak than using starter fluid? any instruments?
Title: Re: Gs500E trouble cruising
Post by: Ugluk on August 25, 2019, 09:05:14 AM
Do you by any chance have the hose to the carb bowl vents in the wind?
I did and it caused these exact symptoms. I had unknowingly routed mine to accompany the drainhose down behind the right side of the engine and experienced mid throttle highway surge. After spending a few hours on this forum i found out about "crosswind surge" and found my problem.
By then I had alreday cleaned my carbs, dissasembled my petcocks, serached for cracks and leaks and moved around my needles dozens of times to no avail.
Title: Re: Gs500E trouble cruising
Post by: flambert on August 28, 2019, 11:13:53 PM
Quote from: Ugluk on August 25, 2019, 09:05:14 AM
Do you by any chance have the hose to the carb bowl vents in the wind?
I did and it caused these exact symptoms. I had unknowingly routed mine to accompany the drainhose down behind the right side of the engine and experienced mid throttle highway surge. After spending a few hours on this forum i found out about "crosswind surge" and found my problem.
By then I had alreday cleaned my carbs, dissasembled my petcocks, serached for cracks and leaks and moved around my needles dozens of times to no avail.

That could be it!! I will check today or tomorrow.

Do you have any links about it, don't find anything when I search for it :)
Title: Re: Gs500E trouble cruising
Post by: flambert on August 31, 2019, 02:51:16 PM
Quote from: Ugluk on August 25, 2019, 09:05:14 AM
Do you by any chance have the hose to the carb bowl vents in the wind?
I did and it caused these exact symptoms. I had unknowingly routed mine to accompany the drainhose down behind the right side of the engine and experienced mid throttle highway surge. After spending a few hours on this forum i found out about "crosswind surge" and found my problem.
By then I had alreday cleaned my carbs, dissasembled my petcocks, serached for cracks and leaks and moved around my needles dozens of times to no avail.

Wuhuuu, that was it, now it's an amazing machine :D send me a pm with your paypal, then I will buy you a beer :)

Thanks!