I've got some non-UST Mavic rims that I'm planning to make tubless with Stans rimstrips (cheap from ebay).

The instructions say to drill out the inner bit of the rim around the stem hole but this seems like something that a cack-handed me could quite easily ruin my rims doing – is it necessary or will it work ok without drilling?

It'll work alright, you'll just have a bit of a bump at the valve hole.

Thanks, I'll give that a go and drill if the bump causes a problem.

Paul

you dont need to drill all the way through, just the inner wall of the rim. use a drill bit 1mm smaller than they say and file it smooth after.

You don't even need to do that, I never did anything to my Olympics, in case I wanted to go back to running just yellow tape/valves.

I'm curious, why you are running rimstrips, njee? I've only ever used tape on mine, and wondering what the rimstrip actually gains you?

I ran rimstrips for a while, it made tyres far far easier to inflate. Just use tape/valves on my Rovals, but it's much more faff than the rimstrips.