Yup, I have a dark side. I've got a KAM KA125-5. It's a Chinese CG125 clone with the OHV 156FMI engine and a PROPER carb with a SLIDE, not like the bloody awful Diaphragm one on the Neco! Also like the Neco nobody wants to service it, so technical advice will be requested.
There's nothing wrong with a diaphram carb ! Buy the Haynes manual on Chinese motorcycles, all info is there and here !
Found the manual! I've ordered a new set of sprockets to give the KAM some slightly longer legs. Moving to a 17 tooth front and 38 rear, which works out at about 2.23:1 ish. I just don't want the "5th gear at 40MPH is 7K RPM" vibration because the frequency resonate with my fillings.
The gearbox has pretty low ratios (IMO) to start, so I think 2.2:1 is about as low as I dare for final drive. After all, the poor bugger only has 7HP to play with!
No terrorising the MOPEDS on the KAM! Still at least it means the engine is very under stressed, so hopefully expensive mechanical noises won't occur very often.
OKAY, new rubber fitted (Continental 120/80-16 rear, Metzeler 2.75-18 front), meaning it doesn't "Tramline" now! Also swapped the cogs for the 17/38 combo I mentioned earlier in this thread, which has made a big difference (I can keep up with traffic without my fillings vibrating in resonance with the piston!). The only trouble I've found is that the new front cog means I can't refit the cover to the engine. It doesn't affect rideability, bit it is a small annoyance. I've kept the OEM 14 tooth front sprocket, so if all else fails I can just put that back on for the MOT and swap it back. 14 front and 42 rear gives a final drive ratio of 3:1. The new ones give 2.2:1. 2.2 is probably about as low as you can get away with on an unmodified engine. At least I'm not being gapped by mopeds now!!
