Singlespeed & Fixed Gear - BD bikes frame geometry?

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Walfredo
06-18-09, 02:28 PM
Sorry for another sizing question. About to pull the trigger on a BD bike after tons of mind-numbing research. My brain still can't comprehend the frame geometry #'s and what is track vs road geometry exactly.

I want to get back into riding for fun and exercise basically around urban streets. I'm fairly tall at 6'3" but with a long waist. My inseam is barely 34" from my dangly bits probably closer to 33.5"

I test drove a 07 rush hour 57cm and it felt good. I had about 1.5" of standover room. But the LBS wanted $550 for it, which is more than I want to spend now. At that price I'd spend the extra # for a One Way or Steamroller. So for now I'll get a BD bike. I'd prefer brakes and the ability to run SS and fixed but not a deal breaker.

Rush hour specs (08 couldn't find 07) 22.4" top tube length, 32.16" Standover, 74° seat angle, 74.5° head angle

Moto Mess: 22.44" top tube length, 32.5" standover, 73° seat angle, 73.5° head angle
Kilo TT: 22.6" top tube length, 33" standover, don't know angles,
Dawes/Windsor: 22.16" top tube length, 32" standover, 74° seat angle, 72° head angle

Any advice or feedback on how these bikes will differ in fit and which one may be my best bet is greatly appreciated. I was initially leaning toward a Dawes/Clockwork but think that one may not fit the best.

Regards.

UPDATE: Thanks for the feedback guys. I'm not going to sweat the little differences as I'm now confident that 58 range is best for me. I prefer slightly small over too big and I think the angles of the Clockwork will be nice for my style of riding. So I ordered the Clockwork orange last night in 58cm. I'll fine tune things after some time with the bike as mander suggested. Review to follow after I get it and get some miles in.


devilshaircut
06-18-09, 02:35 PM
From what I know about bike sizing, reach matters more than inseam. So I would pay attention to the top tube length. But you can also adjust reach sizing (fairly dramatically) by changing the stem you are using. The Messenger appears to have the most similar geometry to the Rush Hour that you liked. I think any of those sizes are fairly similar though.

On the Kilo TT, the top tube is longer and the standover is taller. So it is just going to be bigger in both directions for you. The Windsor is slightly smaller.

However, the differences are fractions of inches, which can easily be compensated by adjusting seat post or your stem.

mander
06-18-09, 03:17 PM
57-58ish cm sounds like it'd be in the right ballpark for you. With your long upper body, I think a slacker seat tube angle might put more of your weight behind the BB and therefore help keep your weight balanced better front to back. That said, city riding is not very demanding of a precise fit and I think any of those bikes would be fine basically out of the box. After you get one and have ridden it around for awhile you'll be in a better position to make fine adjustments to fit.

Track bikes meant for mass start races (ie not pursuits, time trials, etc) tend to have steeper angles than road bikes. This puts the rider farther forward and decreases the bike's wheelbase. The net result is that handling, comfort and performance over rougher conditions are all compromised. In return you get better handling on a smooth track, especially under extra g forces in a banked turn.


Turbo Mini
06-18-09, 03:48 PM
I'm 6'2" with a 33ish" inseam have the 60cm Dawes SST AL and I think it fits me very well. Stand over and reach are very comfortable for me