Singlespeed & Fixed Gear - How much does seat tube length matter?

OK, here's the issue:

I've decided my current conversion is a tad too large (58 c-t st and 56 c-c tt), and so I want a new training bike. Basically, I'm considering two options. The first is to get a 53 cm IRO mark v (53 c-t st and 54 c-c tt). The second is to really deck out a univega super-ten that I already have and have been using to get groceries with for a while. At the moment it fits alright, but isn't configured for hard riding, so I can't tell how it would be as a new training bike. The super-ten measures 51 c-t st and 54 c-c tt.

Everything else aside, how much would having a 2 extra cm on the seat tube matter? I'd prefer to just use the old frame and spend the $250 I save on a brooks swallow or something.

Can't you just lower the seat 2 cm to compensate?

that's sort of the basis of my question. But the extent to which the seat post is exposed changes the hieght of the stem, right?

Yeah.
If you lower the seat you wont have the same reach angle so you might want to lower the stem as well.
But, 2cm is not very much at all.
Whenever I buy a frame, I worry much more about the top tube length than the seat tube length when it comes to sizing.

????
Are you trying to achieve the same saddle to handle bar height relationship and can't tell if you can raise the seat post and bar stem accordingly? Can't you tell from the "do not go" marks on the parts? Does the univega have a threadless steerer tube?

if your 58cm c-t seat tube bike is a 'tad' too large then a bike 7cm smaller is going to either 1.) be adorned with a strange looking mountain bike or technomic stem, or 2.) be savagely uncomfortable. i have a friend at 5' who rides a 48cm bike. i ride a 55cm bike at 5'11".

You want to meaure effective toptube. that is measure in a line, level with the ground, from the top of the head tube to the seatpost or tube. This will give you a better idea of the length of the bike, to compare to your old frame. The length of the seat tube is not to big a deal, not as big as the angle anyway. This assumes you can get a long enough seatpost. I like a compact frame, they are lighter, stiffer and easier to toss around. However I like the way a conventional frame looks.
If you go wiht a way smaller frame you will have a queer, slow steering bike because of the real long stem neede to get enough reach.

My question got answered. It was a pretty minor point. Thanks guys. Now to decide whether to get a threaded stem or a threadless adapter.

if your 58cm c-t seat tube bike is a 'tad' too large then a bike 7cm smaller is going to either 1.) be adorned with a strange looking mountain bike or technomic stem, or 2.) be savagely uncomfortable. i have a friend at 5' who rides a 48cm bike. i ride a 55cm bike at 5'11".


Yeah, I'm 5'8" and riding a 58 cm. I come nowhere near making the stand-over height (and in fact my pubic bone doesn't even clear the top tube). By 'tad' too large, I mean there's a half-fist of seatpost showing and I have a 50mm stem on it and I still have almost no bend in my elbows. Just not the right setup, you know?

Yeah, I'm 5'8" and riding a 58 cm. I come nowhere near making the stand-over height (and in fact my pubic bone doesn't even clear the top tube). I saw 'tad' too large because there's a half-fist of seatpost showing and I have a 50mm stem on it. Just not the right setup, you know?

gotcha. i assumed you were a bit closer to the proper size.

threaded stem.

Yeah, but a warning, if I go threaded, I'm probably going to get one with a removable faceplate, all of which are pretty fugly (someone prove me wrong).

I'm afraid this bike is going to be all about functionality.

Yeah, but a warning, if I go threaded, I'm probably going to get one with a removable faceplate, all of which are pretty fugly (someone prove me wrong).

Do a search on the board for Cinelli Frog and Salsa SUL quill stems. Both have removable face plates and are actually decent looking. There are others as well, but I forget their names off the top of my head.

Yeah, but a warning, if I go threaded, I'm probably going to get one with a removable faceplate, all of which are pretty fugly (someone prove me wrong).

I'm afraid this bike is going to be all about functionality.

removable faceplates might not look the best but they make so much sense. i ride brakeless and i want to switch around my bars pretty often and it makes it easy as hell. AND you don't have to worry about scratching your bars as you wiggle it through the small opening like other stems.

Yeah, Its probably going to be this one:

http://aebike.com/site/page.cfm?PageID=30&SKU=SM6373

Which I think looks similar to the Salsa stem (its just a branding thing, right? Aren't Salsa and Profile both owned by QBP?).

I haven't been able to find the Cinelli Frog anywhere online.