2" tires on 20mm rims - go narrower?
 

I've been reading up on rim vs tire width. My Specialized Hardrock has 2" tires on 20mm rims. I'm not going to spend the money to replace the rims. When the tires get replaced, should I look at putting a 42 or 45mm tire on it?

Will a 700C tire work on a 29er rim?

Thanks.

Quick Google search showed i can use 700c tires. Maybe I'll put my 40mm mso's on and see how they perform.

Are you mountain biking with the bike? Or just riding on pavement and gravel?

There's probably no particular need to go narrower. OTOH, experimenting is part of the fun.

Single track. Going narrower it seems would sacrifice grip for tire stability. I'll have to check my current tire size. Thought it was 2" but they seem wider than that.

Why would you go narrower if on the dirt? (unless it's a gravel bike or cyclocross bike) Most folks are looking to go the other way--to put on the widest possible tires for a more supple ride and more grip. The skinniest I've ever run was a 1.9 in the early 90s and while it rolled fast, it was sketchy in turns and downhill. I've only run 2.1 or 2.2 since. Newer tires designs roll fast and have great grip. Currently, I have a 2.2 on the rear and a 2.35 on the front. (your rims are probably too narrow to support the 2.35 but could handle a 2.1 or 2.2--FYI, many tires are actually a tad smaller in real width than stated width)

Unless you're struggling with tire squirm or pinch flats, keep it around 2.0 - 2.1.

I don't understand why you want to go narrower. You can easily go with wider if you wanted. I would not think twice about running a 2.3.