I have recently bought a cota 200 and am very pleased with it other than one niggling thing.

The engine is a bit loud for my liking. The noise it is making is hard to describe but seems to be in the heart of the engine and not a rattle from one side or another. This noise happens as as you kick it as well but does not get worse with revs. Just mainly at idle and slow running. The bike starts first time and runs a treat but this noise is worrying me.

Could it be mains? or maybe a clutch rumble?

It needs to be checked out to be on the safe side so where is the best place to get it looked at in the UK (midlands would be good)

Cheers Ed

I have a 242 that has the same annoying sound. Much like the bottom end is about to fall out or the piston is about to seize. I've been told it is the nicasil cylinder coating is the reason for noise. Not sure but it is aggrevating.

Thats a thought, I will take the head off tomorrow and have a quick look.

Could be something else, this is just what was suggested to be about mine.

the 200 cylinder is just steel no nicoseal (unsure on the 242 ) if it sounds like sand in the engine its more than likely the mains ,if its rattling could be cylinder wear, more of a knocking big end

another thought is are the rubber dampers fitted inbetween the cylinder and head fins as these stop a lot of noise

After investigation I found it is the drive side main bearing at fault. The oil in the clutch/gearbox was very low and smelled of petrol. I think the drive side bearing is lubricated by the gear oil and has burned away and thus let petroil in.

Oh well engine out and sent off.