thegreatwent

I currently have a 57.5cm (measured center to top) Bridgestone RB-1. After some time out after a spill I've found I've lost some flexibility and I feel a little too stretched out on it and I get a pain in the neck. It has a 57.5cm top tube and I have a 120mm stem.
I'm considering trading it for a 54.5cm frame which has a 55cm top tube. On the 57.5cm frame, when on the hoods, I can see the front hub is behind the handlebars. I understand that the ballpark position you want to be in is to have the handlebars obscure the front hub. It appears that I have about 2cm or so to go, so the 55cm top tube on the 54.5cm RB-1 would put me in a better position horizontally. I have a 120cm stem on the 57.5cm, and I know the 54.5cm RB-1 came stock with a 120mm stem.

My concern is saddle to drop difference. On my current bike, I have a moderate amount of seat post showing - maybe a fistfull and a half or more. There is a difference of 3cm in seat tube length on these two frames or just about 1 1/2 inches. I AM looking for a more modern/competitive fit, but I also don't want to break my back and/or have to jack the bars up to the point that it looks ridiculous.
I had the bars pretty low on the 57.5cm.

I also have a 54cm track frame with a top tube of about 55cm and considerable saddle to handlebar drop and I've never really found it uncomfortable.
I don't race, but I enjoy the look and feel of a modern fit, and I like riding fast, alone or in groups, and I ride quite a bit and use my bike as part of my commute.

Do you think 57.5cm to 54.5cm is too significant a difference? I don't have the smaller frame to look at as it's on the East Coast and I'm on the West.
I suppose I could try and find a bike in a shop that matches the new dimensions and see how that goes, but I'd like to see if anyone thinks I'm way out of line before taking the time to do so.

Any input would be appreciated. Thanks!

brian416

how about going down to a 100mm stem?

thegreatwent

I'd thought about that, but I also thought that I'd rather get a frame that is ideal fit, rather than have a frame that's to big and making adjustments from there.
I believe the 57.5cm is just a tad too big and want to go smaller but I just don't know if 54.5cm is too small..

Flash

+1

on my 53cm RB-1, I always felt too stretched out with a 100mm stem. I went to an 80mm stem and that fixed things. Plus you can raise the quill a bit for more comfort.

bostongarden

I'd test out the 54.5 first and see if you can get comfortable...I raced on a 53 (54.5 toptube) RB-1 with 120 stem in the early to mid 1990s and came back to racing about a year ago...like you, I lost some flexibility...I now ride a bike w/ 525 toptube and 100 stem...there are other factors involved too...I went with feel to make my purchase and adjustments...indeed, drop is a factor, but, with a smaller frame, you could end up with more drop, so, be alert to this...

bostongarden

Indeed, I would make these adjustments first...raising the quill does remarkable wonders...then, if needed, go with a shorter stem (and, of course, quill that goes with it)...

thegreatwent

I've got a stem adapter on the RB-1. I wasn't happy with the available bar options, even though I'd really like to use the beautiful Ritchey stem that came with the bike, so swapping stems hasn't been an issue. I started on the bike with a stem of 100mm and got out to 120mm as I got more and more used to the bike and dropped the bars lower and lower as well to give me a nice aero position.
I'm still not convinced that I should swap stuff out to try and make a too big frame fit. Wouldn't it be better to work a frame that's too small than too big?