'90 GSX-R 750
Carbs are '90 stock Mikuni BST38SS with dynojet stage 3 jet kit. (I have drilled one lift hole larger on the slider and drilled main air jet, as listed on instructions)
Airfilters are K&N RU-2922, as listed on dynojet stage 3 jet kit. They have been washed and oiled.
Exhaust is full vance&hines SS2R.
I have never been able to test these 38mm carbs with stock jetting.
Dynojet kit is E3335.
http://www.dynojet.com/pdf/european/E3335.pdf
Problem:
No power on high gear, first 3 gears goes all the way to redline, but then problem gets worse. Been changing now main jets.
DJ146 (same as mikuni 137)
- Very poor top end power, no power on fourth gear. Max speed 140kmh.
DJ150 (same as mikuni 141)
- Little bit better top end power. No power on fifth gear. Max speed 180kmh.
DJ155 (same as mikuni 146)
- When going over half throttle, starts stuttering on fourth gear. Max speed 160kmh.
Tried so far:
Carbs are '90 stock Mikuni BST38SS with dynojet stage 3 jet kit. (I have drilled one lift hole larger on the slider and drilled main air jet, as listed on instructions)
Airfilters are K&N RU-2922, as listed on dynojet stage 3 jet kit. They have been washed and oiled.
Exhaust is full vance&hines SS2R.
I have never been able to test these 38mm carbs with stock jetting.
Dynojet kit is E3335.
http://www.dynojet.com/pdf/european/E3335.pdf
Problem:
No power on high gear, first 3 gears goes all the way to redline, but then problem gets worse. Been changing now main jets.
DJ146 (same as mikuni 137)
- Very poor top end power, no power on fourth gear. Max speed 140kmh.
DJ150 (same as mikuni 141)
- Little bit better top end power. No power on fifth gear. Max speed 180kmh.
DJ155 (same as mikuni 146)
- When going over half throttle, starts stuttering on fourth gear. Max speed 160kmh.
Tried so far:
- Ultrasonic cleaned carbs.
- New carb gasket kit with with needle valves.
- Synced carbs.
- Changed main jets. Instructions says that 150 is the correct one.
- Changed new spark plugs. Tried with NGK CR9EK and CR10EK (current).
- Tested spark. It seems good strong blue.
- Measured coil resistance, both are ok.
- Fuel lines are replaced.
- Battery is charged.
- No visible air leaks.
- Carbs diaphragms seems ok.
- Float level adjusted.
- New fuel tap.