What size cassette

[robgul]

am assuming like dogtrousers that you were speaking of combinations which might "jam", not just cause a bit of rattling/efficiency loss. If you are rob, though this might be fine for you, I don't trust myself.

Not really - my concern is really wear on the components - e.g. my Galaxy has a triple and 34T cassette - it works fine in all combinations BUT the chainline angle must be ripping the teeth and chain quite badly at the extremes and rubs on the front mech (although as it's a bar-end friction changer that can be tuned out).

Rob