The gfriend and I are doing the Way of the Roses in a few weeks with her work colleagues.
I will be doing it on my road bike, the gfriend on her MTB. To help I was looking at putting some slicks or semi slicks on.
Can anyone recommend semi slicks for a MTB?
I think that a lot depends on quite what you're looking for in the tyre. If she's looking for optimum performance there are plenty of very narrow (1.5" or less) fully slicks for mountain bikes right up to 2.35" (or possibly more) semi-slicks like Schwalbe's Super Motos. I ride a rigid mountain bike on road and off and like something to cushion things, so ride 2" Michelin Hard Terrains (now discontinued sadly). Schwalbe Sammy Slicks are fine if you want something the fatter end of the spectrum.