If I have a tiagra compact 9 speed chainset with a 34/50 how easy is it to get a 46t ring so that it’s more suitable for cross racing. I assume the mech and everything else will be fine with a little adjustment.

Can’t tell with rings if they have the right pcd,speed,ramps and pins? Also they seem to be ridiculously expensive £40 or more.

Anyone done it and able to convince me it’s cheap and easy?

Use Spa Cycles. The Stronglights are cheap, and the staff will confirm if they’ll fit.

In theory any 110 rings should fit…in practice you never know. But make sure you get a 46 outer and not an inner.