Mountain Biking - Stem degree and hand position

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Eman
06-10-06, 06:38 PM
I have a rookie question about stems. Would a 105mm stem with a 7d rise (such as a stock Gary Fisher Genesis geometry) allow me to stretch out more than a 105mm with a 25d rise (such as I have rode on some 26 inch mountain bikes) and in effect give me more reach length?

mx_599
06-10-06, 06:41 PM
I have a rookie question about stems. Would a 105mm stem with a 7d rise (such as a stock Gary Fisher Genesis geometry) allow me to stretch out more than a 105mm with a 25d rise (such as I have rode on some 26 inch mountain bikes) and in effect give me more reach length?
use the Pythagorean Theorem

wait...i mean trigonometry. remember SOH CAH TOA

Peek the Geek
06-10-06, 11:44 PM
I have a rookie question about stems. Would a 105mm stem with a 7d rise (such as a stock Gary Fisher Genesis geometry) allow me to stretch out more than a 105mm with a 25d rise (such as I have rode on some 26 inch mountain bikes) and in effect give me more reach length?
The short answer is, "Yes." Unfortunately, I failed Calculus and Pre-calc more times than I can remember, though, so I can't tell you how much more reach you'd have.

roccobike
06-11-06, 06:42 AM
Yes, that change will lower your hand position and stretch out your overall position.
Being an old phart I'm going in the opposite direction to protect my neck discs. I wish I was lowering the rise like you are because you should improve handling since the lower stem will place more weight on your arms and distribute your weigh more evenly across the bike.
By the way, I did pass math, all the way through Diffy Q, just don't ask me to remember any of it.

rm -rf
06-11-06, 07:01 AM
This stem angle chart (http://www.habcycles.com/fitting.html) will help. The chart is based on horizontal angles, not the actual stem angle, so add (90-73)=17 degrees to your stem's degrees to place it on the chart. Use google to convert cm to inches: searching "1 cm in inches" tells you it's .4 inches.

Eman
06-11-06, 11:26 AM
Thanks guys, that helps a lot! With that info I should be able to fit a Gary Fisher very nicely.