Moab moutain bike

I just purchased a Moab 2 Aluminum, Used. I paid about 350 for it, it looks brand new. I am about 5'9" and 155 pounds, this bike is a 15" bike. It looks a bit smaller than the other moutain bikes I have seen, I am an old BMXer so the size of this bike seems about right to me; it fits me good. What is the advantage of the larger bikes, 17" 21" etc...? Is there a general rule for what size of bike a person should ride?

 

Hi KW
The advantages of larger bikes I'll leave to somebody else to discuss, but for me Small is best, My first MB was a 20" frame and it was a cumbersome tub of crap, My bike is now a 17" frame and it is as a pleasure to ride, my mate rides a 14" Marin and to see him weave in and out amongst the trees is a joy, so for me small frame MB's are the best.

I don't know for sure- there are far better qualified people here than me-but I think frame size is more important on a Road bike.

By the way Roadies, If my inside leg is 32" what size frame should I be looking for when I purchase a road bike.(the request to buy a road bike has been passed by my boss(wife) so it's just a matter of going around to find the best deal I can get)

 

You are 5'9" and your bike is a 15"?? That is WAY TOO small for you. Size is part preference and part math. I couldn't begin to tell you the mathematical formula - but I'll bet you that you are not getting the most power possible from your legs on climbs - because you can't possibly be able to fully extend your leg on a 15" bike. If your seatpost is too high, that's bad too. Check out some websites on bike sizing and I'm sure you'll see what I'm talking about.

 

I disagree that your frame is too small. I have a 16.25 frame and I'm 5'10. I also have a very long seatpost and a 110 mm stem. A small frame is easier to throw around on tight singletrack, and the bike usually ends up being lighter. Same goes for road bikes.

 

16.5 is a little better - but I bet it's too small for you too. The longer the seatpost is, the less stable it will be too. Think about the physics of it - all your body weight being held up by that little pole.... the longer it is, and the more stress that's on it...... = not good.

 

I don't recommend it for everyone, but I am using a high-end steel frame, a top of the line seatpost and I only weigh a buck-35. Just keep your seatposts below the max height line kids. I would personally not go above 17. I know the salesmen at the shop would disagree, but I get such an advantage on technical terrain, and no noticible downside anywhere else, I can't see going back to big frames.

 

So here's the scoop, that there 15" is pretty small, because the Schwinn's were spec'd with a measurement from the center of the bottom bracket to the top of the top tube. Long ago, I had a Rocket 88, which is the same geometry as the moab and the homegrown. I'm 6'2" but I have a mutant like 32" inseam, so the 19" bike fit me just fine with the seatpost maxxed. The 21" I tried felt like a pig.

Since you're 5" shorter than I, and the bike is only 4" smaller than the one I rode, I would venture to guess that a 17" in that model would have been better, but I prefer running seatposts at their maximum, they're more flexible at that point and if you have them in the frame beyond their min. insertion point, everything is going to be just peachy. Plus you won't bash your knees or jewels on the top tube on rough terrain. Enjoy, BW.