2006 Gs500f carb problems

[lucas]

Cool, good job on the pictures.

Does the engine backfire if you have the airbox/air filter installed?  With the carbs open like that I think you can expect it to not have the proper fuel mixture.

If i am not mistaken those orings are not necessary for the operation of your carbs.  I have the older style carb so I don't have first hand knowledge about that, but the stuff i have read on this site leads me to believe that.  Also in the photo the oring does not appear to be making a seal around anything and the cap seems to just have a blind hole, perhaps that is an optional thing in the Mikuni carb body that Suzuki decided not to drill out for the GS500.

Also looking at the part diagrams for your year I don't see an oring under the cap.

Here check out the diagram
http://www.partzilla.com/parts/search/Suzuki/Motorcycle/2006/GS500F/CARBURETOR+%28MODEL+K4-K5-K6%29/parts.html

It looks like your carbs are missing items 48 and 49... these newer style carbs have lots of parts and hoses and things.  Verify that you have all the necessary bits.

[GsSA_TX]

Numbers 48, 49 are a breather tube that was just hanging down and attached to nothing. I removed it because it was cracked all around and falling off.

Also it seems that the left cylinder works only when it wants to, intermittently.

I put the air box on and set the mixture screws to 3 turns out and the backfiring is less frequent.

The bike acts like it is fuel starved, will idle for a minute and then slowly die

[lucas]

I heard from someone on this board that the breather tube should be placed somewhere with relatively little air turbulence.  That air pressure variations at those air vents can cause an unpredictable power variations while at speed...  I have not experienced this, but keep it in mind if this something you notice while riding.

[lucas]

If you search for discussions on this forum about backfiring then you will find lots of advice.


Have you checked your valve clearances?

[GsSA_TX]

Since this bike uses a single point signal generator and not a dual point like the older models, if it were bad would the bike not fire at all??

Thinking it could be bad and making one cylinder not fire, but the wires all read 0 ohms and it LOOKS fine, no cracks in any solder joints.

I did take the little block box off of the signal generator and the magnet inside of it was detached and had a chunk broken off of the middle.
I wire brushed everything and put it back together. The bike ran the same.

Could that be an issue??

[lucas]

On my bike the magnets were not glued to the backs of the sensor but were kept in place by the plastic thing.  I think that is normal.  The magnet should not be broken though... that's odd, but it sounds like your broken magnet is still able to send a signal to the CDI.

My intuition is that since you only have one sensor then a bad sensor wouldn't  cause a failure in one cylinder.


You might have a fuel mixture problem, clogged jets, vacuum leak, valves out of adjustment... or something else going on.

You can check for small vacuum leaks by liberally spraying with wd40 and listening for changes in idle.  This doesn't work for big leaks, like intake boots torn to hell.

You can also pull the spark plug wire while the engine is running and observe if the idle changes.  If no change then the cylinder isn't contributing.  You can hold the wire close to the engine or pull the spark plug as well and pop it into the spark plug wire (while the engine is not running) and observe if the spark is intermittent.

It isn't terrible to get shocked by an engine, it is just a bit uncomfortable.  If you don't get your fingers too close to the sparky metal bits you won't get shocked.