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Main Area => General GS500 Discussion => Topic started by: Masterflies on February 24, 2020, 01:36:29 PM

Title: Carbs, troubles on full throttle
Post by: Masterflies on February 24, 2020, 01:36:29 PM
Hi! Dear Carb Gurus, please kindly show me the direction to dig ) I've adjusted floats, put brand new float needles, their seats and o-rings, works well on idle, but on full throttle all goes weird:



Whyyyy ((( Needle jet? Diaphragm? Please help

Title: Re: Carbs, troubles on full throttle
Post by: herennow on February 24, 2020, 01:42:36 PM
All jets original?
Title: Re: Carbs, troubles on full throttle
Post by: Masterflies on February 24, 2020, 02:00:39 PM
Needle jet is not, I think it could be the cause, but better to ask before, cause I'm really tired of this carbs dismounting exercises )
Title: Re: Carbs, troubles on full throttle
Post by: mr72 on February 24, 2020, 04:17:03 PM
check that the slides are moving correctly, then diagnose from there.
Title: Re: Carbs, troubles on full throttle
Post by: Masterflies on February 25, 2020, 02:53:12 AM
Quote from: mr72 on February 24, 2020, 04:17:03 PM
check that the slides are moving correctly, then diagnose from there.

Which slides you mean? Butterflies? They move perfectly
Title: Re: Carbs, troubles on full throttle
Post by: Masterflies on February 25, 2020, 02:57:08 AM
The Buddha, you know everything, please help )

Trying to understand if it is Main jet, Pilot jet or Needle jet problem...
Title: Re: Carbs, troubles on full throttle
Post by: mr72 on February 25, 2020, 05:07:33 AM
Quote from: Masterflies on February 25, 2020, 02:53:12 AM
Quote from: mr72 on February 24, 2020, 04:17:03 PM
check that the slides are moving correctly, then diagnose from there.

Which slides you mean? Butterflies? They move perfectly

I'm getting too old for this. SMH
Title: Re: Carbs, troubles on full throttle
Post by: The Buddha on February 25, 2020, 05:56:09 AM
Quote from: Masterflies on February 24, 2020, 01:36:29 PM
Hi! Dear Carb Gurus, please kindly show me the direction to dig ) I've adjusted floats, put brand new float needles, their seats and o-rings, works well on idle, but on full throttle all goes weird:



Whyyyy ((( Needle jet? Diaphragm? Please help



You're giving it full throttle in neutral when stopped ? - sorry I didn't watch the video cos I'm at work.
Cool.
Buddha.
Title: Re: Carbs, troubles on full throttle
Post by: Masterflies on February 25, 2020, 06:32:11 AM
yeah but thats just for the video - it loses power before the throttle is full
Title: Re: Carbs, troubles on full throttle
Post by: The Buddha on February 25, 2020, 07:04:01 AM
Jetting depends on throttle position, so at what position does it start to lose power and what does it do when it loses power - misfire ?
Cool.
Buddha.
Title: Re: Carbs, troubles on full throttle
Post by: Masterflies on February 25, 2020, 07:17:11 AM
That's hard to describe by words, but it's on the video ) So if you have 2 min after your work plz kindly take a look ))

It starts to lose power definitely after 4-5k RPM
Title: Re: Carbs, troubles on full throttle
Post by: The Buddha on February 25, 2020, 07:38:31 AM
4-5k when riding ? Or at idle. At what throttle position. I may not be able to till tomorrow. You should describe it as well.
Cool.
Buddha.
Title: Re: Carbs, troubles on full throttle
Post by: Masterflies on February 25, 2020, 07:44:58 AM
At idle. when opening full throttle and constantly keeping it fully opened, RPM goes down, and starts 'waving', like, 1sec below 1k, 1 sec tries to rise, and then again goes below 1k...
Title: Re: Carbs, troubles on full throttle
Post by: The Buddha on February 25, 2020, 11:04:58 AM
You're getting 1k and lower at full throttle ?
Where is the idle set ?
It will idle but full throttle does less than idle ?
You've got a completely plugged pilot circuit.
What does it do on the choke ?
And what type carbs 89-00 or 01-02 or 04-09 ?

Cool.
Buddha.
Title: Re: Carbs, troubles on full throttle
Post by: Bluesmudge on February 25, 2020, 02:04:07 PM
Does your tank have any rust? Are you sure you put the needles and diaphragms back together correctly?

Bike is clearly not getting enough fuel to maintain the throttle position you are at. That surging is weird though...I'll let buddha and mr72 continue to chime in because I've never seen that before.
Title: Re: Carbs, troubles on full throttle
Post by: mr72 on February 25, 2020, 03:10:06 PM
I'm done chiming in. Y'all can help this person figure out what the slides are.
Title: Re: Carbs, troubles on full throttle
Post by: Bluesmudge on February 25, 2020, 04:34:12 PM
Slides are the things that.....slide. Around the needle. You can lift them with your finger to test the function. Not the butterflies.
If anything with the diaphragm or spring or needle was installed wrong you may be able to tell based on the slide function.
Title: Re: Carbs, troubles on full throttle
Post by: The Buddha on February 25, 2020, 07:46:25 PM
Oh jeez, it revs and revs and revs and open the throttle full and it falls on its face, I'm thinking you've still got a plugged fuel passage.
Slides not lifting also possible, but you don't rev to full throttle under no load to find their problem, it will rev fine and run great to 1/2 throttle but never get over that if your diaphragms are bad, causing slides to not lift.
Cool.
Buddha.
Title: Re: Carbs, troubles on full throttle
Post by: Masterflies on March 01, 2020, 05:10:13 PM
Thank you guys,

Changed Main jet + Needle jet - all good now!!!
Title: Re: Carbs, troubles on full throttle
Post by: The Buddha on March 02, 2020, 04:32:37 AM
Quote from: Masterflies on March 01, 2020, 05:10:13 PM
Thank you guys,

Changed Main jet + Needle jet - all good now!!!

OK then. Any idea what the numbers on the mains were ? and needle as well, assuming you installed a knitting needle or something in there so it will make you a new sweater.

PS: I get it, you installed the jets from the rebuild kit from your other thread. You could have cleaned the original mains, that was likely the problem, but its fine, you're good, sorry for being an a$$ - and I'm leaving that comment as proof I was an a$$. LOL.

Cool.
Buddha.
Title: Re: Carbs, troubles on full throttle
Post by: herennow on March 02, 2020, 02:10:09 PM
Quote from: Masterflies on March 01, 2020, 05:10:13 PM
Thank you guys,

Changed Main jet + Needle jet - all good now!!!

Knew it  :woohoo:  !!