I rejetted my bike 96 gs500 with a dyno stage one.  After this the idle was reeeeaaal slow, so I adjusted the idle screw now it stumbles on take-off.  Any suggestions?

Stumble on take off... = rich. You have stock pilots in it??? if so... check your floats, if you have 40's check your air screw. Set that to 3 turns if its more, or screw it in 1/2 turn at a time if its already at 3.
Cool.
Srinath.

Guys what are the odds that one of my carbs is not working?  I had a second or two at lunch and tried adjusting the pilot screws and noticed a difference only on the left one.  The right one could be screwed all the way in or out withput any noticable change.

OK right one is sucking air... it runs at higher throttle openings right... then air.
Cool.
Srinath.

It took awhile but I stilll have issues with this bike.  I tried the wd40 check for leaks and found nothing.  Where do I check next?  I'm at a loss.  Is it time to take it to a mechanic?

Shay

Does the bike seem like it is running on one cylinder at idle?
If so, it might be that the carb is not fully clean. Check by idlling the bike from cold and feel for heat at the header pipe. If the pipe does not heat up, try cleaning the carb out and blowing the orifices with compressed air.

Quote from: caddmonkey1Is it time to take it to a mechanic?

Up to you I guess, but any shop work will be $$$.  If you get desperate, you might "unjet" the carbs back to stock and make sure the original setup still works.

If not, it kinda sounds like you're running on one cylinder, which is more likely electrical than fuel-related.  (Especially since the air/fuel mixture screw had no effect on the one side.)

Thanks guys I'll try to find out more tonight.  If it is electrical what could I have screwed up by removing the carbs ( 15 million times)?  Can anyone tell me the proper procedure to check the float height to get it right I've had these carbs off and on too many times to count.

 


Shay

I can't think of anything you could do to the carbs that will cause an electrical problem.  I just thought that maybe something unrelated to the carbs may have changed.

Feeding off of zlei's post:   If you have any reason to suspect that the left carb is not totally clean, you may want to do a good carb cleaning before you're all finished.

Meanwhile, checking the float height is easy; adjusting it is the hard part.  :mrgreen:   See my Float Height Check page for the first procedure.  For instructions on how to adjust the float height, see Step 7 on this page from the Haynes manual.  The only missing bit of information is that the measurement in figure 9.7 should be 14.6mm +/- 1.0mm.

If it's electrical, in your case, a pulling of the sparkplug wire off the sparkplug to see if that sparkplug is not firing, would be simple enough.

But, yeah, check the carbs.

OK guys I adjusted the  float height.  It is now good.  I then took the plug wires loose and when I removed the right one the engine died.  I had no change when the left one was removed. OK,  I am  running on one cylinder.  I then pulled the plug and cleaned it. No change where should I go from here?

Thanks in advance

Shay

I hate to do this to ya, but ...

...try giving a read through the first two pages (!!) of the old thread Narrowing down the problems to a broken bike.  There are a couple of detours and delays in the "narrative", but by the time you reach the checklist at the bottom of the 2nd page you should have a good feel for why you're checking the listed resistance values, and where to check.

Let us know if you get stuck, or what your results are.

Before you get TOO far along, you may want to follow A_Rivers' lead.  (Read his 2nd post in the thread Need help already... searched.)

Sounds like he's having similar problems....

I have a progress report and a question.

I switched the left plug to the right side.  NO change
I tested all the wires and connectors discussed in previous threads.  They were all good.

Ignition coils good.

For some reason I decided to start the bike again and disconnect the plug wires.  When I disconnected the left side plug wire I dropped it.  I noticed as it was setting against the cylinder Head that the plug wire was sparking through the body of the plug wire cap to the Cylinder head.  It also sparks from my hand to the bike frame. Should this happen?


Shay

Yes it will and the other ine should as well... 30,000+ volts will go through anyhting ...
Cool.
Srinath.

Quote from: caddmonkey1I noticed as it was setting against the cylinder Head that the plug wire was sparking through the body of the plug wire cap to the Cylinder head.
Shay

Should not spark THROUGH the cap - from the open end of the cap to the frame/cyliner it should.  If it sparks through the cap then the cap is cracked or otherwise bad.

OK

I had the bikes compression tested today.  Its good.
Changed the spark plug caps, so they're good now.
I had a chance to talk with the mechanic while we were checking the compression, he said it has to be the carb.  So I brought it back home and lowered the float height a tad on the left side. No change.
So I tried the yamaha carb cleaner. No change.  
I took the carbs off exchanged the float and float needle from left to right.
NO change.

Anybody got a suggestion.  

Maybe drain a little gas and add a match?

Shay

Quote from: KerryIf you get desperate, you might "unjet" the carbs back to stock and make sure the original setup still works.

OK look for rips in diaphragm or some like that, or send it to me.... I'll sort it out and send to you, just pay shipping, of course dont send me carbs with 1/2 the parts awol....
Cool.
Srinath.

Hey guys

Good News.  The bike now runs on both cylinders.  Pilot jet was clogged.

Now the bike bogs down in mid range.  4000 rpms or so.

I'll do some searches to see if I can find out how to solve this.

Thanks to everyone for your help.

Especially Kerry and Srinath

Shay