Rite, got my hands on some 110 Pit bike,to sure on brand, random Chinese... I have looked at others though and they all seem pretty generic. The gearbox is basically raped, works in some gears but yeah... needs replacing, I have found them on eBay for £30 for thumps and the like. Is it possible for me to change this without something going from bad to worse, the bike otherwise seems alright bar rear wheel and I would quite like to do it for a bit experience. Anyone got any ideas or views? Big reasons for me to avoid doing this? I know the bike is not worth a huge amount but would be cool to get it going..