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Main Area => General GS500 Discussion => Topic started by: Iautorico on November 23, 2014, 11:28:12 PM

Title: Slight backfire from right carb
Post by: Iautorico on November 23, 2014, 11:28:12 PM
Anyone know what can cause a slight backfire in one of my carbs. Engine runs generally smooth.
Title: Re: Slight backfire from right carb
Post by: Atesz792 on November 24, 2014, 03:05:50 AM
Well, we'll need more info than that. It can happen with a healthy engine, or you could have problems, but who knows?
There's a saying in medical circles, a good anamnesis is half a diagnosis. Sometimes even more.
To provide some kind of an answer: mine does that sometimes when the weather's real cold, I warm her up until the cylinders are too hot to the touch, ride off and close the choke. Still only does it when I blip the throttle during shifting, until she's fully warmed up.. I don't think it's much of a problem, maybe a valve clearance check is more urgent than I thought.
Title: Re: Slight backfire from right carb
Post by: Iautorico on November 24, 2014, 07:47:55 AM
Engine is freshly installed 600 miles on engine. Carbs off 01 original engine. Jetted with jets from Buddha( I probably misspelled that).  Exhaust is a wide open shorty I made myself out of a big Gixxer can I had laying around.  Original engine ran fine until I blew the transmission. Carb bowl gasket on that side is leaking. Backfire is minimal and runs fine when off idle. Thoughts?
Title: Re: Slight backfire from right carb
Post by: Atesz792 on November 24, 2014, 03:52:44 PM
Well, if that carb bowl gasket lets something out (leaks), maybe it also lets something in (intake air leak)?
Are your idle mixture screws set up properly?
Or maybe you have some tiny cracks in your intake boots that don't produce any more symptoms?
Out of spec valves?
Or, maybe your bike is completely fine.
Title: Re: Slight backfire from right carb
Post by: Iautorico on November 24, 2014, 05:35:27 PM
I'm leaning towards carb bowl leak.
Mix screws set
Intake boots ? Doubtful
Maybe it is just fibe
Title: Re: Slight backfire from right carb
Post by: Iautorico on November 24, 2014, 05:36:20 PM
(http://tapatalk.imageshack.com/v2/14/11/24/048ff1004cf8f26b5d5f405293875df6.jpg)
Title: Re: Slight backfire from right carb
Post by: Atesz792 on November 25, 2014, 03:19:22 AM
Nice ride! Gotta keep it CLEAN with those lights tho :icon_lol:
Maybe a video would be helpful :icon_question:
Title: Re: Slight backfire from right carb
Post by: The Buddha on November 25, 2014, 08:35:00 AM
Quote from: Iautorico on November 24, 2014, 07:47:55 AM
Engine is freshly installed 600 miles on engine. Carbs off 01 original engine. Jetted with jets from Buddha( I probably misspelled that).  Exhaust is a wide open shorty I made myself out of a big Gixxer can I had laying around.  Original engine ran fine until I blew the transmission. Carb bowl gasket on that side is leaking. Backfire is minimal and runs fine when off idle. Thoughts?

Yea fix the leak, so with all the blue lighting you wont see it light up on fire.
Cool.
Buddha.
Title: Re: Slight backfire from right carb
Post by: Iautorico on November 25, 2014, 01:28:36 PM
Found a gasket in town going to pick it up after work and tomorrow... I ride and I'll post some day time picks
Title: Re: Slight backfire from right carb
Post by: Iautorico on November 25, 2014, 01:29:16 PM
(http://tapatalk.imageshack.com/v2/14/11/25/a5318b0e9a01e2ea82ccdd1386a003c3.jpg)

What yall think about the headlight?
Title: Re: Slight backfire from right carb
Post by: Janx101 on November 26, 2014, 01:35:54 AM
Purty! ... what's the on road beam pattern like? .. good or great?
Title: Re: Slight backfire from right carb
Post by: Iautorico on December 05, 2014, 06:17:43 AM
It's great!
Title: Re: Slight backfire from right carb
Post by: dennisgb on December 05, 2014, 10:35:21 AM
Quote from: Atesz792 on November 24, 2014, 03:52:44 PM
Well, if that carb bowl gasket lets something out (leaks), maybe it also lets something in (intake air leak)?
Are your idle mixture screws set up properly?
Or maybe you have some tiny cracks in your intake boots that don't produce any more symptoms?
Out of spec valves?
Or, maybe your bike is completely fine.

All of the above. Carb leak must be fixed first. Then I would lean toward idle mixture, either you have dirt in there (even when we think they are clean they aren't), pilot(s) are the wrong size, or the screw position is not adjusted correctly. All those that say to just turn the screw a certain number of turns are wrong. Manual setting is for start-up after a carb rebuild to get the engine running. The screws need to be "tuned" to the engine when engine is hot. Each screw needs to be adjusted. Should be set to highest RPM and then idle speed adjusted to proper idle RPM with the idle speed screw on the linkage.
Title: Re: Slight backfire from right carb
Post by: MeeLee on December 05, 2014, 01:47:34 PM
Last time i had it, i think the carbs where out of sync. A piece of rust clogged the idle/mid jet. So far most of my issues with this bike have been rust finding it's way in the carb, clogging the jets.
This bike MUST have a fuel filter. I used a high flow fuel filter. Looks funny, but is functional.
Title: Re: Slight backfire from right carb
Post by: dennisgb on December 05, 2014, 05:58:10 PM
Quote from: MeeLee on December 05, 2014, 01:47:34 PM
Last time i had it, i think the carbs where out of sync. A piece of rust clogged the idle/mid jet. So far most of my issues with this bike have been rust finding it's way in the carb, clogging the jets.
This bike MUST have a fuel filter. I used a high flow fuel filter. Looks funny, but is functional.

I run fuel filters on all my bikes. Dirt and rust will wreak havic with the small orifices.