Sgtsalt

My current frame has a 57cm seat tube. The bike I am considering whether or not to purchase says it too has a 57cm seat tube. But it doesn't say how high the bottom bracket rests off the ground. My current frame is a regular road bike, a Schwinn Le Tour. This second bike is a track frame. It is my understanding that the bottom bracket will probably be a bit higher on this track frame.

So which is worse? going too small or too large? If it is too small I can always raise my seat up. If it is too large, well, I can only lower a seat post so much.

But honestly, I'm deciding between a 57cm seat tube and a 56cm one. Not a big deal ultimately, right? I'm just a bit of a perfectionist and I have a lot of hopes tied up into this frame purchase.

Helllellellellellp!

JoelS

Seat tube height is irrelevant. Proper fit is in the top tube and how stretched out you want to be (or not).

dervish

it is not completely irrelevant...it helps to have proper seat tube and saddle height when riding longer distances, or any distances really. but yes, to the OP, make sure you measure the TT as well

Sgtsalt

Hrmmm intriguing.

I understand the importance of the frames size and how each tubes length will affect how I rest on bike, but I guess I didn't think about that.

calf man

Joel is saying that seat tube length is not as critical as top tube length given the ease of adjusting the seat height. Generally, for an average build, a 57cm frame is good if you are about 6' tall. If you are long-legged 6', a 56cm would probably be better.

https://www.sheldonbrown.com/frame-sizing.html

beethaniel

Read this.....

https://www.rivbike.com/article/bike_...izing_position

zsm

In my opinion, too large of a frame is worse than having one too small. With a smaller frame, it always seemed easier to make it fit to you than a larger one.

bbattle

I guess I'll have to be Captain Obvious and suggest you go test ride the bikes in question.

pyze-guy

But thats for a proper bike fit, not fixed uberhipsterdom bike fit.

queerpunk

There is no "proper" bike fit. There are just guidelines for different types of fit based on different purposes.

I'd say it would be worse to have a bike fit too small than a little bit too large, but it depends on a lot of things.

lukewall

Fit really comes down to reach and saddle-to-bar drop. You really need to get a lot of miles in to understand how you like your cockpit set up; and even then, your fit can change over time.

If you really like the fit on your current bike, take your reach and drop measurements and setup your new frame the same way. The 1cm seat tube isn't going to make too much difference. What i would look at is TT length to make sure it's not too long and i need to run a stem less than 90mm and head tube length to make sure the HT isn't too long or too short to get my bars at the height a I want them.

Ken Cox

You can make a small frame bigger with a longer (or setback) seat post and a longer stem, but you can't make a big frame smaller.

The higher bottom bracket won't make the track frame "bigger."

If you like your 57 road frame you'll like the 57 track frame.

Cyclist0383

It all depends on the geometry of the frame and how it's measured. I have 56, 57, 59, 60, and 62cm bikes that all fit me fine. The only way to know for sure is to ride the bike.

icyclist 

>Fit really comes down to reach and saddle-to-bar drop<

I want to buy a FG/SS bike (my first - I better hurry up 'cause I'm old).

My road bike - a 56cm Specialized Roubaix - has a tall head tube, the saddle is just a little higher than the bars, and that's how I like it - it's a very comfortable ride. On my 58 cm, 1962 road bike, the drop from saddle-to-bar more significant - the head tube is a lot shorter. I don't like the ride as much as when I'm my Roubaix, but a after a few minutes in the saddle, it feels fine.

As I don't race, I don't think there's one "best" bike for me.

But the salesperson at my LBS, when I looked at FG bikes a few days ago, thought I shouldn't be on a bike with a noticeable saddle-to-bar drop. Frankly, I'm not as interested in being comfortable on a FG as I am on my Roubaix - I want some drop on that kind of bike, and aesthetically I like a little more, rather than a little less, seat post rising up out of the frame.

I think it comes down to, within reason, what I want, based on the relative merits of comfort/efficiency/looks, etc.

synapsemusic

i'm pushing 6'5" with a 36" inseam and my 60cm kilo seemed too big at first, but after getting used to the ride and getting my seat up to the proper height it's a perfect fit. i don't think you can "test" a bike for 3 minutes and know if it's going to work out for you...that said, i'd much rather have a bike thats too small than too large. anything bigger than my bike would be a stretch for me

longbeachgary

Just a couple of comments... The height of the bottom bracket doesn't really mean anything. Your seat height is going to be measured from the pedals not from the ground and a more important measure is the top tube. Second, a bike that is too big or too small has to be fitted by changing the stem. A stem that is too long or too short will change the way the bike handles. Also, people with the same height and torso/leg length can be comfortable on different size bikes. It's not just simple science - it's more of an art. (I personally am more comfortable on a larger bike).

exhibitx

Unless it's too high

But yeah, otherwise, I usually base my choice on top tube length ... other things like headtube length, headtube angle and bb drop should be taken into concideration but if you get the right top tube length you've nailed 80% of the sizing

adriano 

it does if youre fixed!

conor

right. i'll always choose a longer seat tube over a shorter, since it gets the bars higher up, which means that i'll be less hunched over over longer distances.

www.rivbike.com

read up on it.

edit: oh, ****. beat to the punch.

edit2: lbs. for serious. talk to 'em.

carleton

If you are THAT worried about it then why buy a bike without trying it on first? There are lots of things that are easy to buy sight-unseen. But, a bike isn't one of them UNLESS you know that a Bianchi 57 or a Trek 58 fits you.

You will get all kinds of suggestions and advice from this forum good and bad. But, only your butt, legs, arms, and back will know if that bike will fit you or not. NOT US.