generate

I'm about to purchase my first modern road bike. I have been riding fixed for awhile now, and I also have a classic road bike that feels a bit big for me. I am very confident fitting myself to a track bike, but I have some confusion when it comes to road bike fit.

I have done online calculators that say I should be somewhere in the range of 52 ST and 52-53 TT. Most of the 52cm road bikes I'm looking at have a 52ish ST and a 54ish TT.

I guess my confusion is this: I know I'm comfortable with a 53cm effective TT on a track bike. Should I feel a bit more stretched out on a road bike as far as the TT goes?

I'm just trying to narrow things down before I pull the trigger...

carleton

It sounds like you are expecting to have a longer effective top tube on the road bike. This will only be the case if your track bike has a really aggressive seat tube angle (like 75 or 76 degrees) and your handlebars are low. Such a seat tube angle allows low bars because your entire body is rotated 2-3 degrees forward with your BB being the axis of rotation. This loads up a lot of weight on the hands, which isn't an issue for track sprinting being that the events are only a few minutes long. Track endurance riders typically use riding positions similar to their road setups with the bars higher providing even distribution of weight. With the aggressive sprint position, the rider's reach is the same, it's just tilted down, but this requires a slightly shorter cockpit when measured level to the ground.

So, the answer is...it depends. But you shouldn't feel more stretched out either way.

Do you know the geometry of your current bike?
What is the make/model/size?
Do you want a similar riding position?
Can you post a pic of the bike from the side?

tFUnK

in general track geometry will have higher BB (resulting in higher standover height), steeper angles, and longer top tube compared to road geometry in similar size. from personal experience a 53 track frame will feel like a 55 road frame, a 56 track frame will feel like a 58 road frame. that's why when people want to ride track bikes on the road, they generally size down one size from their normal road frame size.

carleton

I would very much like to dispel this myth.

I ride a custom track bike with an effective top tube of 57.1cm. My road bikes have always been 57 or 58cm. I have ridden 55/56cm track bikes and there is no way that they fit.

The "you should buy a track bike one size smaller" myth is just as bad as the "you should buy a bike based on stand over height" myth.

Maybe the OP should go and actually ride some bikes at a few shops instead of ordering online blindly using calculators.

generate

My felt tk2 has a 52 ST and a 53ish effective TT, seattube angle of 74 and a headtube angle of 75:


My rossin road bike has a 55 TT and a 54 ST and it feels long. Could I also attribute this to less of a saddle to bar drop since the ST is longer?

I'm looking at a BMC racemaster. Size 52 has a 52 ST and a 54.5 TT

carleton

Nice bike.

The seat tube on the TK2 isn't super agressive. There are road bikes with a 74deg seat tube angle.

How does the TK2 fit without the angled seatpost? That effectively changes your seat tube angle to maybe 72 or something. Setback seatposts are more like problem solvers than anything. They move your butt further away from the BB, and closes up the hips, when most people are trying to get closer to the BB. However, it does shift the weight off of the hands a bit.

Your profile says that you are in NYC. I think your best bet will be to go a few shops and sit on a few bikes and take notes, then go home and look up the specs. Notes like:

Bike: Specialized Tarmac
Size: 54cm

Lookup on the internet:
ETT: ___cm
STA: ___ degrees

Bike: Trek Madon 3.1
Size: 54cm

Lookup on the internet:
ETT: ___cm
STA: ___ degrees

That way you will have a better idea as to what you dig.