MTB holiday insurance

the aa covers you as long as its not for competition. I think snowcard.com or something like that will cover you for competition. they do insurance for off piste skiing etc and where covering people for the mega avalanche
If you are a VHI member they do a multitrip insurance thing for €49, covers you for the year
Multitrip.com (all the adds on the radio) do good value cover including mtb cover wintersports etc if you want it. Discounts for having private health insurance, not needing cover in the States etc. From memory I got a worldwide annual policy including mbt and all other class 1 and 2 hazardous activities plus wintersports cover for about 60 bills-you cant go wrong.