Mountain Biking - Newbie to Mt Bike Terms - Need some Help

I'd normally search to find this out but I'm not even sure what to search for. Been riding road for a few years and am used to the road terminology. Just bought a Giant Talon 29er 1 yesterday and I'm looking at wheels for it.

What are the sizes all about. Example: looking into Crank Bros Cobalt 2's. Have choice of 9mm or 15mm by 135mm. What does that refer to?

It's axle size.
9mm is a standard quick release. Other ones are larger diameter axles, some through axles.

I can't say for sure without looking at a link to what you're looking at, but I'm fairly certain that's talking about axle size(the 9 or 15mm) and the width of rear triangle it will fit(the 135mm). For example, in the front a MTB could have a 9mm quick release axle, a 9mm through axle(I think), a 15mm through axle, or a 20mm through axle. In the rear there are a few choices as well. Then it could be 135mm wide in the rear or a couple other sizes if single speed, etc.

http://www.giant-bicycles.com/en-us/bikes/model/talon.29er.1/9041/48915/ This guy?

Sooo...I don't want to tell you what to do, but I'd upgrade that fork before I changed the wheels. You might take a bunch of rotating weight off with the wheels, but a solid fork will do absolute wonders for your ride. Way more important, IMO. Cobalts aren't cheap...for that same money, you could probably put a Float 29 on there. Your bike has a 15QR, right? I think Fox makes a Float with a 15QR, so you wouldn't need a front wheel yet. Looks like you'd need a 1-1/8 steerer, but it's hard to tell from the picture.

http://www.giant-bicycles.com/en-us/bikes/model/talon.29er.1/9041/48915/ This guy?

Sooo...I don't want to tell you what to do, but I'd upgrade that fork before I changed the wheels. You might take a bunch of rotating weight off with the wheels, but a solid fork will do absolute wonders for your ride. Way more important, IMO. Cobalts aren't cheap...for that same money, you could probably put a Float 29 on there. Your bike has a 15QR, right? I think Fox makes a Float with a 15QR, so you wouldn't need a front wheel yet. Looks like you'd need a 1-1/8 steerer, but it's hard to tell from the picture.

Yes, that's the bike. I have a Pro account with Crank Bro's so the wheels are a much better price than retail. What do you mean solid fork?? What is on there right now and what would be the difference? Also where would I get the specs to tell what axle sizes I would have on my bike. Could not find it on the giant website for the model I have.


Thanks guys!