Hi,

As i look down they inlets in my engine with the reed valve removed, i can see marks on the crank webs where the piston skirts have been catching at bottom dead center. Does this indicate imminant disaster?

If you are sure that the piston is making contact with the cases, or the crank, then I would suspect there is something wrong.

Now I am no expert, but I base this on the fact that the piston shouldn't be contacting anything top or bottom.
_________________
Charles Gallant

Yeah, i wondered if anyone could tell me specifically which part or bearing is worn or failing for this fault to occur. Does it mean a full crank replacement or just the small end bearings? Anyone had this problem before?

Tom,

it could be the small end bearing, or the big end bearing.

For the piston, you shouldn't have any play at all on the small end. Side to side maybe, but nothing else. The big end will have some play, and that is outlined some where on NSR-WORLD (I am sure, just don't know where off the top of my head). But again, I think its mostly side to side play. If you got slop in the crank, then you will need to replace the entire crank.

Thanks,
_________________
Charles Gallant