Bike Fit - Some Opinions?

In article <[email hidden]>

K-Paws said:

I have several bikes. My 'A' bikes are both size 63 Trek 2000's, one from
around 1999 and the other an 06. I really do love riding both of them,
despite my ineptitude at adjusting Shimano derailleurs, (only matched by my
LBS). The Treks, as most Treks tend to be, are very traditional geometry.

For a winter bike (as I have become more keen on riding recently), I thought
I would buy a Specialized Allez, sized 61, it seemed like good value and it
does look very nice indeed. Can't be that much difference I thought. I feel
every bit as comfortable on the Allez, perhaps more so, but I can't generate
ANY power or speed on the brute, it's horrific. I can get up to my
theoretical maximum HR and it still feel as if the axles tied to a heavy
weight or something.

I intend to have it's perfectly acceptable components relocated to a
'traditional' frame, but I am so stumped by this. It just shouldn't be this
bad. Every now and then I think I will try it again, it will be better this
time. But, no it isn't, it's hell itself. Any thoughts I am just amazed
there's such a big difference.

Put the bikes next to each other so the bottom brackets are lined up -
what's in a different place? Stand each bike up with the near pedal at
the bottom, holding the saddle and handlebars, and gently push the pedal
away from you with your foot - is one of the frames significantly easier
to spring? Put the Trek wheels on the Allez - does it ride better?

K-Paws said:

Any thoughts I am just amazed
there's such a big difference.

I've always found it really difficult to set up different bikes so that
they feel the same when you ride them, even if you get all the main
dimensions the same.

Check the following on the Specialized and adjust as far as possible to
get near the Trek geometry that you are obviously happier with. You'll
need a spirit level and plumb-line (ie bit of string with a weight on
the end) to measure accurately:

- saddle height above centre of bottom bracket
- saddle nose distance behind centre of bottom bracket
- height of saddle above top of handlebars (easy to alter unless you've
already cut your Aheadset forks too short - DOOH!)
- reach from nose of saddle to centre of handlebars (may need to alter
stem for a longer or shorter one)

Also check the cranks are the same length as this can make a fair bit
of difference to the feel of a bike.

If the Specialized still feels "dead", maybe it's just the frame
stiffness (or lack of) or the frame angles that feels odd compared to
the Trek. Not much you can do about that but change the frame.
Generally, a stiffer frame with more upright seat tube geometry will
feel faster but give a harsher ride.

in message <[email hidden]>, K-Paws

(') said:

I have several bikes. My 'A' bikes are both size 63 Trek 2000's, one from
around 1999 and the other an 06. I really do love riding both of them,
despite my ineptitude at adjusting Shimano derailleurs, (only matched by
my LBS). The Treks, as most Treks tend to be, are very traditional
geometry.

For a winter bike (as I have become more keen on riding recently), I
thought I would buy a Specialized Allez, sized 61, it seemed like good
value and it does look very nice indeed. Can't be that much difference I
thought. I feel every bit as comfortable on the Allez, perhaps more so,
but I can't generate ANY power or speed on the brute, it's horrific. I
can get up to my theoretical maximum HR and it still feel as if the axles
tied to a heavy weight or something.

I intend to have it's perfectly acceptable components relocated to a
'traditional' frame, but I am so stumped by this. It just shouldn't be
this bad. Every now and then I think I will try it again, it will be
better this time. But, no it isn't, it's hell itself. Any thoughts I am
just amazed there's such a big difference.

Where you touch the bike is the triangle saddle/bottom-bracket/bars. What's
the difference in the dimensions of that triangle between the Allez and
the Trek?

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