Grand Prix 125
Main Motorcycle: 97 speed triple
Join Date: Mar 2016
Location: Raleigh NC
98 t509 cutting out at idle- when warm
Hey! Thought I would ask you all. I am not able to figure this out. I’m mechanically inclined and I am stumped!
I won this bike at a copart auction a couple months ago.
The bike is a 98 with 21k mile. It did not run when I got it- no key got a key made and it fired right up but would cut out at idle when warm.
Compression test came to 110 on 2 cylinders and 105 on another. Granted I think the gauge is off as my friends cb550 could only do 60 compression on all cylinders.
The bike when warm will develop a miss and cut out at idle.
Coil packs (used)
Spark plugs (old ones were fine)
Professionally cleaned fuel injectors (injectors were clean already doh)
All vacuum lines to iacv- I kept the check valves
Fuel lines in tank look fine, I replaced clamps with fuel injector hose clamps.
The air box does not go on super tight it will sit on the throttle bodies snug but a good tug takes the air box right off.
This didn’t help.
After I checked compression the bike did get a check engine light. I’m assuming this will go away after a couple of cycles.
Any ideas I’m thinking maybe it’s the fuel pressure regulator
I’m connective the top fuel pump line to the long line that is on the left side of the bike.
Short line to the bottom fuel pump line.
At this point I’m going to give it a tune ecu scan but that will take a day or 2 as my friend has an Android and I do not haha.
Thanks in advance!!
98 t509 roulette green raleigh, nc