fury413rb
Been Around the Block
Right now I cant control the idle on my KZ. It races up to about 3,000rpm right after you start it. The only changes I made were pulling the float bowls off and changing just the main jets. Went from 97.5 to 107.5. I did not remove the carbs from the bike this time.
While it is running I have sprayed all over the carb boots and the carbs themselves trying to find a vac leak - nothing at all.
This is where it gets weird. I fill the float bowls and pull the tank off and start it.
BAM idles at 1500 rpm and you can blip the throttle and it returns back to idle fairly normally. BUT then I notice I forgot the plug the vac line for the petcock. As soon as I plug that the bikes instantly revs to 3,000rpm and becomes hangs really bad when you blip the throttle. It runs better WITH A VACUUM LEAK.
I pulled all of the float bowls again - all the floats are fine, don't appear to have moved and are free - not hung up on anything.
Fill the float bowls again - started the bike with the vacuum line unplugged so it was idling at 1500rpm again. Spray carb cleaner all over the place and didnt get any rpm spikes - sprayed it into the vacuum line and it revved up so at least the bike responded.
The idle thumbscrew has no effect on lowering the idle in either scenario so something is still wrong. I readjusted the throttle cables to no effect. If I do force the throttle shut the small amount that it can go the bike does rev down.
The outboard plugs are super black and the inboard plugs are not so black.
Could I have the wrong jets? I posted this on the KZ forum I am on and no one and any input other than what I have already checked. The only thing I can think to do is put the old jets back in. They appeared to be identical to the 107.5 jets thought.
The bike has green dyna coils, new wires, NGK plugs, vm24 slide carbs with the accelerator pump bowl replaced with a standard bowl (this had no effect on anything either and it has new diaphragms), kerker 4-1 with a fresh packed baffle (removed baffle to no effect), new points and condensers (ran fine for weeks before - changed to old set to no effect) and has a stock airbox that I checked for obstructions and has a fresh filter. The carbs have air screws, not pilot screws and they have not been touched. I would not think a main jet change would necessitate an air screw adjustment as I did not change the needle position or pilot jet.
Literally the only thing I did was pull bowls, change main jets and reinstall the bowls. I am really really stumped. I don't think its ignition related because they are paired at the coils as 1&3 and 2&4 which isn't reflected by the color on the plugs.
Am I missing something stupid here?
While it is running I have sprayed all over the carb boots and the carbs themselves trying to find a vac leak - nothing at all.
This is where it gets weird. I fill the float bowls and pull the tank off and start it.
BAM idles at 1500 rpm and you can blip the throttle and it returns back to idle fairly normally. BUT then I notice I forgot the plug the vac line for the petcock. As soon as I plug that the bikes instantly revs to 3,000rpm and becomes hangs really bad when you blip the throttle. It runs better WITH A VACUUM LEAK.
I pulled all of the float bowls again - all the floats are fine, don't appear to have moved and are free - not hung up on anything.
Fill the float bowls again - started the bike with the vacuum line unplugged so it was idling at 1500rpm again. Spray carb cleaner all over the place and didnt get any rpm spikes - sprayed it into the vacuum line and it revved up so at least the bike responded.
The idle thumbscrew has no effect on lowering the idle in either scenario so something is still wrong. I readjusted the throttle cables to no effect. If I do force the throttle shut the small amount that it can go the bike does rev down.
The outboard plugs are super black and the inboard plugs are not so black.
Could I have the wrong jets? I posted this on the KZ forum I am on and no one and any input other than what I have already checked. The only thing I can think to do is put the old jets back in. They appeared to be identical to the 107.5 jets thought.
The bike has green dyna coils, new wires, NGK plugs, vm24 slide carbs with the accelerator pump bowl replaced with a standard bowl (this had no effect on anything either and it has new diaphragms), kerker 4-1 with a fresh packed baffle (removed baffle to no effect), new points and condensers (ran fine for weeks before - changed to old set to no effect) and has a stock airbox that I checked for obstructions and has a fresh filter. The carbs have air screws, not pilot screws and they have not been touched. I would not think a main jet change would necessitate an air screw adjustment as I did not change the needle position or pilot jet.
Literally the only thing I did was pull bowls, change main jets and reinstall the bowls. I am really really stumped. I don't think its ignition related because they are paired at the coils as 1&3 and 2&4 which isn't reflected by the color on the plugs.
Am I missing something stupid here?
