My VF250 Montesa originally had a Bing 54 38mm Carbie which has worn slide, needle, needle jet & body like most of them. I would prfer to keep the Bing but parts are just so expensive and the Spanish Bings are even more difficult to get parts for. I have a 38mm Mikuni VM installed. Can anyone suggest a conversion for the jetting.
Bing Jetting
Slide No23?
Main jet 175
Pilot jet 50
Needle 8G3
Needle jet 2.84
Current Mikuni jetting
main jet-280
pilot jet-40
needle-6FJ6
needle jet-159Q6
With the Mikuni fitted the bike runs but will not run at low speed under load (just dies if you try to ride it) It looks like to pilot jet is way lean as to get the engine to run OK in neutral the air screw is only 2/3 turns from fully in.
I thought someone may have some way of converting the Bing settings to Mikuni equivalents or at least ball park values. Jared Bates, SW Montesa supplied the jetting values but they would be for his location in the US although I would think the needle, needle jet and slide should be close.
Any suggstions?
