Thanks very much for all your help guys, I thought this might be quite an involved job,my mate is planning to do the scottish 2 day so I guess the Delorto is out of the question, so does anyone know what carbs would be permitted or failing that, has anyone got a similar carb on their cub & is running ok? if so what jetting/needles etc etc do you use, the ignition is a new pvl from Millers so I would at least think that that should be OK,although I know even new products can give problems, but unlikely I would think.