itguy1984
08-09-2010, 12:43 PM
Hello,
I am a local bike shop owner (Small business) and we are having some very odd issues with a 95 GSXR 750.
the bike came in with a laundry list of issues. To help bring the bike back to life we did the following
UltraSonic clean the carbs
Carb Jet Kit (122.5 Main Jets + Needle work)
4 rebuild kits for the lower end of the carbs
All new OEM Wires + ignition
K&N Air Filter kit
When the bike came in it it was DOA. After the carb work we got the bike back up and running with a dead spot around 2.5K. After riding it for a while it was getting worst. We took the carbs back apart to find that the O-Rings we used for the Internal Choke system were a little to big and they would not allow the tubes to sit correctly. We got a set of rebuild kits for the lower end. This got the bike to run and run very well. The issue is the 122.5 Jets are a little to rich and now the bike is killing spark plugs. We down Jetted the bike and now it will idle (Pilot Jets seem great) but when we crack the throttle it kicks out a bunch of black smoke and wants to bog/die.
When the carbs came off last time Carb#3 had the return slide spring smashed up in the top of the cap (Bike was still running VERY strong). So we repaired that issue and down jetted to
Carb1: 112.5
Carb2: 110
Carb3: 110
Carb4: 112.5
(Before Jetting Change)
Plug 1: Rich
Plug 2: Perfect
Plug 3: Rich
Plug 4: Rich
My question is...
Has anyone on this forum had a run around with these Mikuni carbs? My thoughts are to up jet it just a little more (117.5 all around) and bump the needle a little richer (from 3 to 4).
We have over 20 years of experience with carbs and normally do not have much issue at all but for some reason this bike seems to have some ghosts.
Either way. Any war stories or opinions would be much appreciated. Looking for educated opinions.
Thank you in Advanced
I am a local bike shop owner (Small business) and we are having some very odd issues with a 95 GSXR 750.
the bike came in with a laundry list of issues. To help bring the bike back to life we did the following
UltraSonic clean the carbs
Carb Jet Kit (122.5 Main Jets + Needle work)
4 rebuild kits for the lower end of the carbs
All new OEM Wires + ignition
K&N Air Filter kit
When the bike came in it it was DOA. After the carb work we got the bike back up and running with a dead spot around 2.5K. After riding it for a while it was getting worst. We took the carbs back apart to find that the O-Rings we used for the Internal Choke system were a little to big and they would not allow the tubes to sit correctly. We got a set of rebuild kits for the lower end. This got the bike to run and run very well. The issue is the 122.5 Jets are a little to rich and now the bike is killing spark plugs. We down Jetted the bike and now it will idle (Pilot Jets seem great) but when we crack the throttle it kicks out a bunch of black smoke and wants to bog/die.
When the carbs came off last time Carb#3 had the return slide spring smashed up in the top of the cap (Bike was still running VERY strong). So we repaired that issue and down jetted to
Carb1: 112.5
Carb2: 110
Carb3: 110
Carb4: 112.5
(Before Jetting Change)
Plug 1: Rich
Plug 2: Perfect
Plug 3: Rich
Plug 4: Rich
My question is...
Has anyone on this forum had a run around with these Mikuni carbs? My thoughts are to up jet it just a little more (117.5 all around) and bump the needle a little richer (from 3 to 4).
We have over 20 years of experience with carbs and normally do not have much issue at all but for some reason this bike seems to have some ghosts.
Either way. Any war stories or opinions would be much appreciated. Looking for educated opinions.
Thank you in Advanced