gitaneusa.com :: View topic - Seat post diameter for '86-87 Team Pro?

tjchad

I had a cursory bike fit check done last week at the local Trek store and it was recommended that I raise my seat. My post is already at the minimum insertion line so I guess I'm looking for a longer post... YAY! what would be the diameter of the seat post I need?

sandranian · Site Admin

I think it is a 26.4, but can verify tonight. Might it be that you need a bigger frameset?

tjchad

Bigger frameset? Possibly. My standover puts the toptube just touching. This frame is 55cm ctr to ctr. I had to shorten the stem on it also.

sandranian · Site Admin

Checked. Mine takes a 26.6.

tjchad

Thanks man. Now to decide if I can get away with this frame or... what.

sandranian · Site Admin

I don't understand: If the standover height is "just touching", why would you need a long(er) seatpost? What kind of seatpost did you have in there?

tjchad

Standover refers to top tube to crotch with both feet on the ground, right? When I had the basic bike fit done I was told the seat was too low and had too much "bend" in my knees- I think it was appr 38*. I'll have to grab the print out to be more exact. I had always thought just setting the seat height so that your extended leg can just touch the lower pedal with the heel was all I needed and now I'm told I need more height to the seat. I don't know... The bike feels OK to me.

sandranian · Site Admin

Your first "fitting" technique is more accurate. You should just be able to touch the pedal on the down-stroke with your heel. Be careful for "Trek" professional bike fitters. You will likely be too high in the saddle, which will lead to "rocking" and then to hip/back pain.

tjchad

The measurements from the fit put the angle of my knee at 48* and he said it should be more like 30-35*, maybe even 28*. I did raise the post a little (that's why it is now at the minimum insert point) but it was already pretty close- I could only raise it a few mm's.

Thanks Stephan! I'm still looking into getting the frame painted to the correct color with new decals. I LOVE the original blue color of the Professionals- sexy bike...

verktyg · Last edited by verktyg on Sun Jul 04, 2010 10:27 pm; edited 1 time in total

Many so called expert bike fitters fancy themselves as ballet maestros!

They think that fitting a bike is like molding little girls into totally artistic but unnatural ballet positions and moves.

Once you get past 18 years old, you body becomes set in it's ways. The older you are the less likely their theories can work for you.

A lot of these theories are based on trying to develop world class cyclists not to adjust YOUR bike for a comfortable fit for YOU!

In the early 70s I read the Italian CONI book (their Olympic Team guide book) cover to cover a number of times. I finally realized that I was over 30 and not one of their 14 year olds they were trying to mold into future champions!

Late last year (against my warnings) one of my riding buddies took the advice of one of these fit Nazis with a Trek or some other program - different bars, stem and saddle - down on the drops, ass up and head down.

After several weeks of that crap, at 47 years old he ended up at the chiropractors to get his back straightened out! He could hardly go to work much less ride!

In a properly fitting bike unless you are looking to became a competitive cyclist, it's more about weight distribution than aerodynamics!

You should be looking for a weight balance between your seat and legs with a minimal amount on your hand, arms and shoulders.

Minor adjustments to you seat height, angle and forward to rear position can make a world of difference in riding comfort.

Same thing with the bars but you have the additional issues of stem length and bar reach.

I find that a seat height adjustment of as little as 1/8" or 1° angle can make a big difference in comfort.

Also, after I haven't ridden for a while I sometimes have to drop the seat a little and raise it back up again later.

A friend of mine was on several US National Teams. The first time we rode together (on a social ride) my friend said my toes were pointing inward and that's why I had knee problems. Sure enough that was it.

My point is that achieving a comfortable ride is more important to casual riders than forcing your body to adapt to an uncomfortable position!

Frenchbuilt

Your right! I was 16 when I bought my TDF and the bike felt good no matter what and I changed around lots of things. But when I got cleats put on
I started to have knee problems and my doctor put me on aspirin to reduce swelling. I found out that my feet were canted and pointed out on one side and being locked in so tight to the pedals my knees were hurting and swelling. What I remember doing was grinding away the narrow slot in the cleat to give it more clearence for rotating and once everything loosened up
things got better. But my back hurts no matter what from 30 years sitting poorly over the drawing board and so I put on the silly looking Mafac Randonner brake levers (see in photos of my 30$ bike) , like my first Varsity, and this really helps.

Dan

tjchad

thanks guys! I ended up finding a longer seatpost. I may end up with it where I started but I have a little more room to play around now. I put a shorter stem (110mm) with a slight rise to replace the 130mm one I had on there.

verktyg

I had a bike out for a spin today that I hadn't been on in over a year.

After about 3 miles I stopped and adjusted the seat and bars.

I raised the seat about 1/8" (3mm) and tilted the nose up several degrees because I was feeling too much pressure on my hands. Finally I rolled the bars back a few degrees so that my hands felt more comfortable on the tops just behind the levers.

After another mile I stopped and dropped the nose back down about a degree. The rest of the ride was perfect - like I'd been riding that bike non stop for the past year. Very Happy

I've developed a system for setting up my bikes. I have a cheap plastic dial protractor with magnetic base that I use for setting the seat and bar angles.

http://www.thefind.com/family/info-magnetic-polycast-protractor

My seat angle at the very rear is 10° nose down- last year it was about 11-12°.

The flats of my bars are about 5° downward angled at the rear of the levers.

With a crank arm parallel to the seat tube at the bottom of it's rotation, I measure the distance from the pedal spindle to the top of the saddle. This year it's 87cm - last year it was 86cm.

tjchad

Thanks Chaz, I have a sweet digital Mitutoyo protractor I use as well. I just don't believe bike set up is as "exact" as the guy doing my "fitting" tried to make it out to be- your experience shows how you have to play with the setup a little sometimes. I myself see how my two different size bikes both seem to fit me fine- my Gitane's seatube is 56 cm ctr-ctr and my Performance is 58 cm. And let's face it- I'm not Lance Armstrong and Trek, or anybody else, isn't going to build a bike to my exact specifications anytime soon! Very Happy