Reply To: 2007 GT250R – carb help [Solved]
Did you change the Pilot Jets ? (if yes they should stay at Size 20 forever) and is the airbox ON ? They don’t really like to run without the OEM airbox attached to it.
(Weird upside down CV carb physics)
It sounds silly to say this but have you checked the sparks on both cylinders?
Also, remove the intake pipes going to the cylinders and check their o-rings. Just even a tiniest leak from there runs the whole bike as they are very fussy when it comes to that , its easy to lose vacuum without realizing it. The previous owner may not have touched them since it was new, but enough heat cycles over the years will necessitate the replacement of those O-Rings.
Find something like this exactly:
Spray the inside the AIR FILTER CATRIDGE or the AIRBOX INSIDE = About 3 seconds worth of spraying. Then fit everything back in nicely including the tank.
Do this outside the garage if possible as this stuff can light up in flames if anyone is smoking near you or weird sparks happening from electric sockets in garage, etc…. I can’t stress this enough.
Put the bike on Full Choke. Start it and let it scream for 2 mins on choke, make sure it has fresh new fuel.
Slowly wind down the choke lever and adjust the Idle Screw Tickover at the same time until it revs around 1500 rpm cold (it will rise to 1800 max when its hot which is maximum recommended) although Hyosung says 1500 max all day , i find 1800-1700 sweet enough. Don’t exceed 1800 rpm as you will be very slowly cooking pistons idling in hot traffic.
See if these tips helped ?