Re: Bike fitting and used bikes

In article <BOydnWwqhdSog4rVnZ2dnUVZ_uadnZ2d@xxxxxxxxxxxxx>,
"Bruce Gilbert" <bgilbertREMOVE@xxxxxxxxxx> wrote:

"Ralph Barone" <invalid@xxxxxxxxxxx> wrote in message
news:invalid-81DF99.22134328042008@xxxxxxxxxxx
Can anybody offer up some suggestions on how much adjustment capability
is in modern road frames? I'm looking at a few used bikes which seem to
be smaller than what I think I should be buying, but I don't have a good
feel for how bad it would be to buy an undersized frame and then just
crank up the seatpost and maybe lengthen the steerer tube.

PS: I'm 5' 10", 32" inseam, and the two bikes I was looking at were 50
cm and 54 cm frames.

For a man of your size, a safe bet would be to look for a bike with about a
55cm effective top tube. That is still the best way to measure a bike. Look
for how to measure the frame for effective top tube and go from there.
Unless you have unusually long legs and a very short torso, or vice versa,
the 55cm top tube should get you reasonably close to a proper fitting frame.

The 50cm, as others have noted will be too small to work. Depending upon the
manufacturer and their respective geometry, the 54 may work well. I have
seen what were called 54cm frames go from a 53 top tube all the way to 57.
Therefore, measure the top tube and forget what size the manufacturer
describes the frame as. With the advent of compact geometry bikes, the
effective top tube measurement has become increasingly important.

I hope this helps,

Bruce

Thanks to all. No time to post more now, but I will digest and follow
up later.
.

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