Mountain Biking - Should I get a small?...

I'm shopping around for a mountain bike. I'm a bmx'r but I want something with some gears so I can climb hills and commute a little further.

I understand how a mountain bike is supposed to fit but the small ones feel A LOT more natural to to because I'm used to a bmx bike. I'm comfortable with my knees coming up high and having a low center of gravity.

I think I'm just going to go with a small bike.

Is there anything I'm forgetting to take into consideration here?

Thanks.

I think you should buy a small.

I understand your leaning to a small bike since you ride BMX. But, you will get used to a MTB that is fitted to your size. You will feel cramped on a smaller bike and you wont be able to make the manouvers that are required for MTBing. Trust me you will get use to it....:thumb:

I tried the same thing the first time I went mountain biking. I had the option of a well-fitting 18" frame & a small 16", & went with the 16". I could have had the seat all the way up to utilize all my leg muscles while sitting for the flatter portions of the trail, but I put it all the way down because I used to race BMX & that was what felt right to me. I ended up completely exhausted only half way through the trail & thought that mountain biking just wasn't for me. Then I was convinced to give it another shot on a larger frame with the seat up a bit higher & loved it. I know the BMX fitting feels right, but mountain biking is a whole different kind of exhausting & mountain biking with a 26"-wheeled BMX bike is only fun for freeriding when you're standing up 90% of the time anyway. When you've been riding for 10 miles & have had the option the entire time to sit while still properly extending your legs to pedal, you'll be glad you have a well-fitting mountain bike.

Personally, I find a BMX bike to be a blast on MTB trails. Nice and nimble, for those twisty areas. I do keep my seat cranked up, so I can sit on the flatter areas.

If, you're going to get a mountain bike, you should probably get one that's properly fitted. MTBs are designed for a different riding style, than BMXes. You can't just set one up like a cruiser.