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Layback seatpost to increase horizontal length(5 posts)

Layback seatpost to increase horizontal lengthtrainerjosh
Apr 29, 2003 8:02 PM
I'm riding a 62cm Jamis which, according to my fit from www.zinncycles.com/fit/, is a good fit for all of my vertical measurements, ie: seat tube length, bottom bracket height, and seat height. The problem is my horizontal measurements. Zinncycles.com suggested a 130mm stem; my bike has a 120. Also, my top tube length is supposed to be 59.4-61.3. The top tube of my bike is approx. 57.5-58. I was thinking that if I got a layback seatpost and then pushed the saddle all the way back on the rails, that would help get me to my number. What do you guys think? Do you know of any layback seatposts that might give me 2cm or so? The cheaper the better, as always. Also, I'm looking for a good bike rack for the bed of my truck. Any help here appreciated as well{:^)
Nothing cheapMR_GRUMPY
Apr 30, 2003 4:57 AM
The Easton EA70 costs about $70 and the EC70 is about $110
Both have lots of setback.
re: Layback seatpost to increase horizontal lengthSpiderman
Apr 30, 2003 7:34 AM
moving your saddle back would effect your knee-over-spindle measurement. Usually, to attain proper upper torso length, a longer/shorter stem is used. Also, not that i am doubting Leonard Zinn, but designing your "ideal" fit over the web may not be the perfect solution. I know if you ask ten people how to get fit, you will hear 10 different answers, but there is always your local bike shop who can actually see what they are doing. Not forcing anything on you, merely a suggestion.
wrong approach...C-40
Apr 30, 2003 9:24 AM
Stem length should be used to change your reach, not the saddle position. With a 62cm frame there is nothing wrong with using a 130 or 140mm stem.

The saddle position is supposed to be fine-tuned for the optimum combination of torque and cadence to produce the most power. If you push the saddle back 2cm, you will probably lose cadence and have to make it up with more torque.

Have you ever checked your position relative to the bottom bracket? That's where bike fitting starts. After the saddle is set, then the stem length can be adjusted for the proper reach.

Try www.cyfacusa.com for decent fit info.
Not necessarilymarron
Apr 30, 2003 2:16 PM
My personal experience (TIFWIIW) is that you are better off extending the "reach" in both directions. I don't buy the KOPS argument that there is some magic sweet spot relative to the pedal. If you're tall, you're probably better off with a much more rearward position than is possible with most frames. Why do you suppose Merckx uses a 71.5 seat tube angle on his large frames?

While there is nothing wrong with a 140 stem on a frame that size I bet it will balance and handle better with a 130. On the other hand if all you do is ride in a straight line and never turn "in anger" than just stretch out the front end.