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It’s from ‘96 so very old, and likely revved long beyond when the bearings wore out.
There’s only one used cylinder available on ebay for £150. Considering there’s at least one stud with nut still on the outside, I bet it needs some work too.
As I understand it looking at the parts stockist, the rod alone (if available) will cost as much as the NOS crank assy, even before labour on top. Maybe I just bite that bullet on the new assy.
pdlouche
@Jung
That looks like a plated cylinder to me, probably Nicosil - in which case, you don't bore them. They get replated and honed, usually at a fairly extravagant cost. It looks worn, but you really can't tell unless you measure it. Generally if you can't see any evidence of hone marks, plated cylinders are usually in need of redoing.
If you've up and down play in the crank, it needs rebuilding for sure. Unless new cranks are very available and cheap, you usually press out the pin (with a bloody great 20ton press) and fit a new rod kit with big end bearing as a set. It would be weird to do all that and not replace the rod. It shouldn't be too expensive.
I'd look around on the bay for a less used cylinder - Nicosil bores last a frigging age if they're looked after. I'm surprised to see that wear on a trials bike - my CR250 is 2001 and on the original cylinder!