XS250 VM32 carbs

Hi,
I present myself, my name is Diego and I have been trying to build a Yamaha Xs250 as a cafe racer for over 2 years. I have done almost everything to get the engine work as it should, changed piston, piston rings an so on (the engine wouldn´t start when I bought it). The engine is now runing as I have changed the carbs form BS-32 to VM-32 both Mikunis, But the engine is runing Way to rich in every curve of the throttle, it runs for 20 minutes and the plugs goes all black. I' am usinig the following set of jettings 90 main,35 pilot, 6dp7 jet needle2.0air jet, 159q-6 needle jet. Does some one have used the VM32 on an xs250? do you know the jettings I should use?

diego84 said:

Hi,
I present myself, my name is Diego and I have been trying to build a Yamaha Xs250 as a cafe racer for over 2 years. I have done almost everything to get the engine work as it should, changed piston, piston rings an so on (the engine wouldn´t start when I bought it). The engine is now runing as I have changed the carbs form BS-32 to VM-32 both Mikunis, But the engine is runing Way to rich in every curve of the throttle, it runs for 20 minutes and the plugs goes all black. I' am usinig the following set of jettings 90 main,35 pilot, 6dp7 jet needle2.0air jet, 159q-6 needle jet. Does some one have used the VM32 on an xs250? do you know the jettings I should use?

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Hi Diego. Did you ever work out what was the problem? I am now in a similar problem, have just rebuilt an xs250 and put on VM 32s, plugs go black after 5 mins? Any Ideas?

Thanks mate
Cheers
Paul

vm32 is way to big for that bike for street use im not sure you can get them right

i use vm28 baby 28s small form factor