That would be an interesting article. I ride a 55-56cm road bike with a 56 cm top tube for road and a 53-54 top tube for tri positioning. That seems to work well for me.

I ride a 17.5" or 18" mountain bike with a 23" top tube (44.5 cm and 58 cm top tube). I keep the seat about a centimeter lower on the mountain bike--lower center of gravity and better handling in singletrack. It's hard to say how I came to that conclusion other than it feels right. But, a lot of the mountain bike websites have rider height ranges listed with bike sizes since so many just come in XS, S, M, L.

---

Brandon Marsh - Website | @BrandonMarshTX | RokaSports | 1stEndurance | ATC Bikeshop |

Thanks for the reply, -Tex.

I also go with what feels right, but I have been proven wrong for my road bike position. I wonder how the body angles translate into Mountain Biking and I would really like to see Dan's knowledge applied to mountain bike riding. I should probably mention that I have a x-country bike and that is the kind of riding I am interested in.

While I am at it, I wonder if Cervelo ever considered building mountain bikes. Imagine a X-country version of the Prodigy!

Good question... I also have a X-country bike that I plan to race this summer and I've been fiddling with the saddle position. Right now the saddle is farther back and flatter than I would have thought was good, but it's working for me. I, of course, have no idea what I'm doing as far as positioning on a mountain bike, it just feels good this way.

I'm 5'10 with long arms and legs and I ride a 56cm Kestrel KM40 with a shortish stem (100mm) and the saddle all the way forward. My mountain bike is a Large Trek Fuel 98 with Monkey Lite low risers, and my saddle is almost all the way back on the rails, and parallel to the ground.

Any advice?

---

___________________________________



http://irondad06.blogspot.com/

http://irondad.blogspot.com/

Since we are on the subject of non road bikes... what is the difference between a road bike and a cross bike besides the brakes and the fork?

Could you take an old road frame and use it as a cross bike?

Assuming you mean Cyclo-Cross and not a Hybrid bike, the basic difference is the frame geometry of a Cross bike has a little longer chain stay for tracking stability, a higher bottom bracket for clearance and a larger main triangle opening to allow for shouldering the bike easily. Generally, the cross frames will ride much like a touring bike and often people will use them for commuting. They are great as a winter bike. But to really appreciate a Cross bike, you need to race Cross, it's as much fun as you'll have on two wheels. Awesome workout, and great for bike handling skills.