Whacked a rock right on the kick start shaft, then the nasty whirring noise started. Bike started and ran but making hideous noise. It was exiting the last section so just rode it back 500 metres to the van.

Any ideas?

is it an sy2t?

Edited November 30, 200817 yr by godzilla

Yes it is.

Best thing to do is drain the oil and water remove the kickstart and the brake lever. Remove the bottom water hose too. This will expose the kickstart gear. from there you should be able to get a better idea of what the problem is. I would expect that when you drain the oil it will look like metallic paint.