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Main Area => General GS500 Discussion => Topic started by: Krazer12 on May 17, 2025, 01:45:15 PM

Title: Carb issues I cannot figure out
Post by: Krazer12 on May 17, 2025, 01:45:15 PM
Hello all, I'm back.  More issues I can't figure out, and it's frustrating.

So, to start, I had a post on here a while ago about vacuum leaks.  I found that leak, it was on the vacuum port of the right carb where there was a small amount of corrosion.  So, I actually went ahead and bought a set of clean carbs off a low-mileage wrecked GS500.  I put them on, and voila!  The bike ran.   I *did* also put on new carb boots, just because it was apart and I had a brand new set.

After that, the only issue it had was 7500(ish)RPM and up WOT bogging, and ash-white plugs —running lean.  I identified it as being lean from the aftermarket exhaust.  So, I went up from a 130 main jet, to a 140 main jet.  Still had that bogging, starting either the same or maybe slightly lower at 7000(ish)RPM, with *slightly* more tan (but still pretty white) plugs.  Ugh.  So I put in 150s, and I swear it's gotten worse yet.  And now, one plug is a bit darker and one is pretty damn white.  For reference, my test rides are generally 5-10km, and I got the jets on Amazon (maybe makes a difference, but idk).  This is all a PITA, and I'm sorry for having to come back to the board with questions.

Krazer12
Title: Re: Carb issues I cannot figure out
Post by: Armandorf on May 19, 2025, 07:11:10 AM
Low mileage could still be clogged if not stored correctly, are the idle mix screws tapered?

Title: Re: Carb issues I cannot figure out
Post by: Armandorf on May 19, 2025, 07:14:01 AM
Also, check your valves clearances, and sync the carbs(take note of current position)
Title: Re: Carb issues I cannot figure out
Post by: cbrfxr67 on May 19, 2025, 11:30:17 AM
I'd go back down and go through those carbs too,...  You'll get it but it takes a few times and patience.  Keep messing with them,..