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Another Fitting

Muirenn2011-04-18 17:20:49 +0000 #1
I finally got around to having a real fitting for my old steel bike. The geometry was off, I knew the handlebars had to be raised and the stem was at max, but I didn't expect this!

Before and after below

The lbs ordered a new seatpost too. The current seat post is original to the bike and very short. Plus the diameter is 26.8, so they didn't have any in stock.

Took it out for about 15 miles afterwards. The tall stem is a little odd to get used to, but the fit is right.

In another post, I used the fit-kit numbers to ask about compact steel frames. Wrong numbers since bikes are measured differently for sales purposes. I knew it was off, but didn't know how to fix it.

I need a seat tube of about 56 with an effective top tube of 53. Not really standard, but I'll figure it out eventually
TxDoc2011-04-18 17:34:56 +0000 #2

as a disclaimer, please be aware that I am not an bike expert and neither a fitter... but frankly this seems a very odd way to solve the problem. In other words, it seems more like 'patching' a problem rather than truly solving it.

Realistically speaking this is what I would have done/suggested for the same issue:

1 take out the current headset, quill stem, and fork

2 get a threadless headset with a bit of stack and a new fork

3 take your body measurements and cut the steerer tube of the new fork at the correct length for your fit

4 use the above body measurements to get the correct length/rise stem for your fit

5 rebuild the bike with the new headset/fork/stem

Again - don't take me seriously, I don't build bikes for a living...

but what's been done here seems very odd to me.

I'm sure the real experts will chime in soon with some more helpful comments.
Muirenn2011-04-18 18:02:49 +0000 #3
It's definitely a patch-job. He offered to do about what you said, but didn't advise it. This is a 20 dollar yard sale bike, and going to that expense just isn't worth it. He actually recommended selling it. Which I might do in the future after putting it back the way it was. This old-school geometry (men's) isn't even close for me.

I'm just using it to go to the coffee shop to avoid paying parking fees without worrying about it getting stolen. I lock it up, of course, but my other bike isn't practical as an around-town bike.

Thanks Doc! Nice to see a real solution. But the bike just doesn't fit. The bike in my avatar (and in the background of the first picture) is women-specific. And even that has a shorter stem than what came on it.

I'm wondering what bike I can possibly get off-the-shelf that will fit well. The C'dale is actually too small. But at least the top tube is fine.
TxDoc2011-04-18 18:04:14 +0000 #4

Originally Posted by Muirenn

I'm wondering what bike I can possibly get off-the-shelf that will fit well.

I hear ya, sometimes being able to fit on stock bikes off the shelf becomes quite hard.

One way to look at it is to go custom. From the 'perfect fit' standpoint is probably the best decision, but of course it takes more time and can be expensive.

Another way to solve the problem - is to start by determining the top tube length needed, and let that determine the size to pick. Then, to decide among the stock geometries available with that TT length, use the other measurments to determine the bike model that will fit the required measurements (seat tube length, seat angle, hed tube etc) with the least adjustments. This is actually what some of the racers do, since they have a limited choice due to sponsorship. Some sponsors build them customized bikes, others just fit them the best way they can on what is stock production.

With longer legs and shorter torso, then the TT determines the size and then (provided that the athlete is flexible enough) the seat tube length gets 'made up' with the seatpost, sort of. Of course all staying within reason

and trying not to look like this...

So you would have to look for a frame geometry that is already set for you body proportions. Right off the bat I cannot think of anything - I am actually the opposite and always try to stay away from short TT...

But - I can tell you a few that I tried and recall as having 'terribly short top tubes' for me... which could put them on the list of bikes for you to look into: Cervelo S2, Lapierre FdJ (I tried to fit on that one desperately

), and the Ridley with the integrated seatpost. The Cervelo I recall as the one that felt the shortest.

Not sure this helps but good luck!



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