Dellorto UB22 BS Carb Tuning.

Tux 120 · Post by **Tux 120** » Tue Oct 25, 2011 9:22 am

I have fitted a megaphone type silencer to my Gilera 124 5v, removed the air filter and wondered if anyone has any knowledge of jet sizes that may be required for this set up.

I have fitted a 110 main, up from 95, and fitted an adjustable jet screw in place of the float bowl securing nut. The idea being, if the main is to big, I can close it down a little with the screw, and up from 260 needle jet to a 262.

The bike starts well, and after warming up, runs well too, however it will not idle, it seems to race at about 2000rpm, and will eight stroke if slowed down, suggesting a rich mixture. Turning the mixture screw has little or no effect on this.

I fitted yesterday, a NOS Dellorto UB 24 BS that I came by. This has yet to be road tested, but the idle problem is the same.

Any help would be appreciated!

Thanks