Question on transferring fit from 1 bike to another

Triathlon Forum
1

Hi all,

further to my wheel ponderings, I’m now pondering a frame change next year if I decide to go 700 rather than 650 (oh the slippery slope). Last year I had a John Cobb fitting, and went away very happy with how the bike felt, and with a page of measurements so I can put the bike back the way it should be after each trip to a race. It’s been very comfortable since then.

Now, would those measurements be the same on a different bike.

The sort of distances I have seem to me to set my body in the correct position, which should be close to ideal regardless of what you change around it. The measurements that put your skeleton in a set position won’t change, so could I set another bike up the same way.

measurements are:
a, Bottom bracket to top of seat (3.5" from nose)
b, bottom bracket to saddle nose offset
c, nose of seat to center of handlebar
d, nose of seat to center of steering tube
e, nose of seat to center of shifter mount
f, center of front axle to center of shifter mount
g, center of front axle to center of elbow pad
h, width of aerobars
i, width of aerobar pads

of these, the ones that I think should remain the same are a,b,c,e,h,i. the others would vary according to the geometry of the frame and the wheel size.

Reason to ask is, as I live in Borneo, I would have to mail order a frame, build in with the 105 parts off the current bike, but larger wheels, and set it up according to JC’s measurements.

Is this right, or would I be missing something important.

Cheers,

Justin.

2

Seems reasonable, but d, f and g will vary a bit depending on frame construction, does not need to be equal to your current frame.

3

Hey Justin,

Check out www.cyclemetrics.com

The Fit Stick is the best thing to transfer position from one bike to another. I have one, and it is the best positioning tool I have used…much more precise than a level and measuring tape. All of my bikes fit exactly the same using this tool…I can get off of one and get on another and not tell the difference. It’s $140 USD, but worth every penny!

Make sure your new frame has the same top tube length, or close…within a few millimeters. Even if the seat tube angle is a little different, you can change the effective seat tube angle with the seat position.

Good luck with the new bike!

John

4

Thanks for the link John. I’ve been though the website and must admit I don’t see it being worth $140. If you’re in a shop environment, it might be very neat for speedy setups, but for me, I don’t see it being more accurate than using a tape measure and inclinometer carefully and taking my time.

When I had my setup, all the measurements of the bike were done with a tape, and that’s how I rebuild it each time. I can get everything within a couple of mm, and a tape is much easier to pack into the bike box.

Neat it does look mind.

Cheers,

J.