bike fit
Last Post 08/07/2013 06:46 PM by Steve Lindell. 7 Replies.
Author Messages
THE SKINNY

Posts:409

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08/05/2013 08:52 AM
after riding for years i've finally gotten to the point where it's become painful to ride my current setup. my kneecaps ache and my neck would get a kink in it. i splurged for a bike fit after getting good reviews about the local shop from some of my fellow riders. first off my saddle was way to low and to far back hence the knee pain. my saddle is way to soft but i left in on for now. next some inserts for my shoes to push my knees away from the top tube and get them more in line with my hips and feet. next was the bar height and reach. my current bike is from the last millennium so i'm stuck with a quill stem which made swapping parts difficult (actually impossible because they don't have any stems or adapters for a 7/8" steerer tube). we ended up raising the stem quite a bit but the reach was still to far. it felt much better but not great. i rode 55 miles on saturday and i didn't start aching until about 40 miles in. the soft saddle and the taller saddle position worked against each other and my soft tissue areas after a while so i'm swapping the saddle to something more firm. i'm in the market now for a new bike. the problem is i sort of fall between two different sizes. i need more height in the head tube and less reach in the top tube. i could go with a larger frame and a short stem and fewer spacers or a smaller frame with a longer stem and a stack of spacers. the endurance frames tend to have taller head tubes. i don't race so i'm more about comfort than quickness.
How we spend our days is, of course, how we spend our lives.
Cosmic Kid

Posts:1136

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08/05/2013 09:56 AM
Did the fitter give you a table of coordinates and measurements following your fitting? Specifically, did he give you a suggested "Stack & Reach"? Those are the key corrdinates you need to compare against different size frames from different manufacturers. S&R elimiates the variables of different angles, "effective top tubes", etc.

Just because you fall between two different sizes form one manufacturer doesn't mean that applies to all manufacturers. Check other bike options form different brands to help find the "right" fit.

Based on your descriptions above, I woudl definitely lean towards a "Gran Fondo" type bike, which will give you more height and less reach than a "standard" road frame.
Just say "NO!" to WCP!!!!
THE SKINNY

Posts:409

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08/05/2013 10:21 AM
as far as the saddle position, i've got s&r. the bars we couldn't get due to lack of swapable parts. i'm in the ballpark though.
How we spend our days is, of course, how we spend our lives.
Cosmic Kid

Posts:1136

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08/05/2013 10:39 AM
Hmmmmm...S&R should be independent of saddle position. S&R are based on dimensions from the end of the rear wheel. Once you have your S&R set, you saddle is then measured based on your current saddle position relative to the BB.
Just say "NO!" to WCP!!!!
THE SKINNY

Posts:409

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08/05/2013 10:58 AM
i've got the saddle position set based on the stack & reach from the bottom bracket.
How we spend our days is, of course, how we spend our lives.
Cosmic Kid

Posts:1136

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08/05/2013 11:06 AM
OK, so if you have those numbers, it is basically a math game at this point. Compare them against the S&R of other frames youa re considering, add / subtract distances for the stem length, additional spacers, etc.

Your biggest "challenge" will the fact that you don't have an exact HB position, only one that is "pretty close". So you'll have to guesstimate where your "ideal" position should be. But with the large variety of stem choices, you should be able to get dialed in pretty easily.

Slowtwitch (I believe) has a database of S&R numbers for most of the major brands on their website. You may wanna dig around a bit.
Just say "NO!" to WCP!!!!
THE SKINNY

Posts:409

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08/05/2013 01:46 PM
the stack and reach was super easy to transfer to my other bike. i used one of those squares that they use for cutting sheet rock. just stand the bike up straight and set the square on the ground with the vertical arm centered on the bottom bracket. a tape measure and a level are all that's needed to get the dimensions.
How we spend our days is, of course, how we spend our lives.
BlueCooper

Posts:2

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08/07/2013 06:46 PM
If you are coming from an older bike with older handlebar/brake lever setup be sure to factor in the changes in the handlebar reach and drop and that the shifters are longer and tend to be higher up the curve. Measuring to the contact points on the shifters and bars will give better numbers than to the end of the stem.


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