dannydan

I'm looking to get the Trek Domane 4.3 and debating between a 54 and a 56. One shop I've been to told me I'm a 56 and another said 54. According to Trek's sizing chart I'm 56. I've test driven both and they feel fine, but I can't really tell from a 5 minute ride around a small parking lot.
I am 5 9" with an inseam of 30.5". Thoughts?

Thanks in advance!!

deapee

54 without a doubt.

Don't let the bike shop talk you into a 56 because it's what's on their floor. And if you like the colors of the 56 better, just order the 54 in the right colors.

Looks like the Trek sizing chart for Domane puts you right at the top end of the 54 or the very bottom of the 56.

Garfield Cat

One thing is to go to a bike fitter who is not connected with any bike shop. Tell the fitter what you want to do and ask how the fitter may help.

GoWolfpack

For your height, definitely 54cm. Having ridden both under-sized and slightly over-sized bikes, under-sized is easier to deal with.

jefnvk

Tis all subjective to the individual. All mine are oversized in most people's opinions, but I find them easier to handle and more comfortable.

SkyDog75

You and I are almost identical in height and inseam and I typically ride 54 cm frames. I can comfortably ride 56 cm frames, too, especially on a modern frame with a sloping top tube. I'd just need a slightly shorter stem.

Either would work for me, but I'd prefer the 54. I'd guess you're probably in the same boat unless you've got oddly-proportioned t-rex or monkey arms.

Wilfred Laurier

I would guess 54, although both would probably be acceptable. There is often a range of two or three sizes of a model of bike that a person can fit, not a binary 'right' or 'wrong'.

bruce19

Bike fitting has little to do with simple height measurement. I am now down to 5'9" with a 32" inseam and I can ride from 54-58 with proper mods.

Wheever

Another vote for 54. I'm about your height, but with a 33" inseam, and I ride a 52 Domane. Accounting for the difference in inseam puts you on a 54.

fietsbob

30.5" include your feet? You Do the stand over, lift the front wheel test? how far did you get the wheel Up?

Im 5'9" (down from 5'10" at 65+) my horizontal top tube 56 has a 565 top tube and a little over a Fist width of post out.

A sloping top tube would have more post out ..

Bars height relative to the saddle matter ? go fast, Racing, bent way Low, or something more comfortable for Century rides ..

trailangel

56 without a doubt. You have short legs and a longer torso, you need longer top tube of larger frame.

philbob57

How did you measure your inseam?

I'm 2"+ shorter than you, my cycling inseam is 30.75", and my torso is long for my height - I comfortably ride a 1973 MKM bike with a 54 seat tube, 56 top tube, and 10 cm stem. That's all within the French Fit recommendation from Competitive Cyclist. A 56 bike's top tube would be jammed up against my pubis.

I think there's a good chance you measured your inseam wrong for cycling.

canklecat

That's getting into the A Lot of Money category, at least on my skinny budget. I'd pony up for a bike fit to be sure, since it's a fraction of the cost of that bike. With my history of neck pain even a seemingly slight change in riding posture matters. Heck, for that kinda money, I'd hope the shop would include a fitting (assuming I didn't beat 'em to death over the asking price).

Camilo

I have opposite experience and opinion. But....

I agree, either is very likely to be acceptable - I believe both the seat post and stem lenght would be within normal for both (probably longer for both in the 54, shorter for the 56). The length and height of the top tube (these are the things that determine the "size") probably would work for either.

To me, you should simply look at the head tube length and decide which suits your handle bar height needs better.

If you like the bars relatively lower compared to the saddle, get the 54. If you like the bars closer to the saddle height, get the 56. Of course you might able to achieve either preference with both, depending on where you want the bars and whether minimum or maximum spacers would do it for you with either frame.

But if you like a lot of saddle-bar drop, get the 54, if you like minimal saddle-bar drop get the 56, you probably can't get both of those extremes with both frames.

That's why I said I had the opposite opinion to the first quote above - I happen to like my bars up close to saddle height, and that's a little easier to do if I "err" on the larger side if I'm in between two sizes. I just like the feel of a taller bike too.

The person quoted in the first quote probably has the opposite preferences to me, therefore it's easier to get what he wants with by erring to the small side.

Hope that makes sense.

dannydan

I measured it according to the guidelines here. I just double-checked and same result - 30.5" inseam.
Btw, here are the results I got from that calculator:
[TABLE]
[TR]
[TD="bgcolor: #fefefe"]The Eddy Fit (cm)[/TD]
[TD="bgcolor: #fefefe"]
[/TD]
[/TR]
[TR]
[TD]Seat Tube Range c–c:
Seat Tube Range c–t:
Top Tube Length:
Stem Length:
BB–Saddle Position:
Saddle Handlebar:
Saddle Setback:[/TD]
[TD]51.4 - 51.9 cm
52.9 - 53.4 cm
54.1 - 54.5 cm
10.1 - 10.7 cm
65.4 - 67.4 cm
53.9 - 54.5 cm
7.4 - 7.8 cm[/TD]
[/TR]
[TR]
[TD="bgcolor: #fefefe"]The Competitive Fit (cm)[/TD]
[TD="bgcolor: #fefefe"]
[/TD]
[/TR]
[TR]
[TD]Seat Tube Range c–c:
Seat Tube Range c–t:
Top Tube Length:
Stem Length:
BB–Saddle Position:
Saddle Handlebar:
Saddle Setback:[/TD]
[TD]50.2 - 50.7 cm
51.7 - 52.2 cm
54.1 - 54.5 cm
11.2 - 11.8 cm
66.2 - 68.2 cm
53.1 - 53.7 cm
6.2 - 6.6 cm[/TD]
[/TR]
[TR]
[TD="bgcolor: #fefefe"]The French Fit (cm)[/TD]
[TD="bgcolor: #fefefe"]
[/TD]
[/TR]
[TR]
[TD]Seat Tube Range c–c:
Seat Tube Range c–t:
Top Tube Length:
Stem Length:
BB–Saddle Position:
Saddle Handlebar:
Saddle Setback:[/TD]
[TD]53.1 - 53.6 cm
54.6 - 55.1 cm
55.3 - 55.7 cm
10.3 - 10.9 cm
63.7 - 65.7 cm
55.6 - 56.2 cm
6.9 - 7.3 cm[/TD]
[/TR]
[/TABLE]

I'm totally confused by this - according to these results should I go for the 54 or 56?

Paul Barnard

What you are finding out is that, like most riders, you can comfortably ride two different sizes.

MRT2

I think the answer is, you need a 55 cm.

Spartacus713

You are not more or less manly based on if you have a larger bicycle frame size.

Buying a bicycle size is like buying clothes. Get one that you will be comfortable with. In your case, I suspect that is the 54.

philbob57

It looks like you measured right but mis-typed your height in your OP - 69" instead of 66".

I'd say go for the 54, if you're choosing between 54 and 56. Based on my experience, I'd recommend checking out a 52.

I owned a 1972 58 cm Gitane for a year or so, until I came down on the TT too hard - until then, though, it worked for me. I followed that with a 1971 50 cm Gitane for 6-7 years, and it was really too small, more because of TT than ST. Over-reaction.... Right now, I'd like a little more space between me and the TT, but I weigh a lot more now than I did 35 years ago, and I've probably shrunk a bit, too.

I'd like a 52, which is why I recommend it to you. There may be something wrong with that reasoning....

dannydan

Not sure what you mean. I am 5'9" (176cm) tall.

dim

use the eddy fit (top results) ..... you need a 52

SkyDog75

...except that a 52 cm Domane's top tube is too short. A 54 cm frame is the one whose effective top tube length is in the 'Eddy Fit' range. If he went with a 52 cm frame, he'd need a long 120 mm stem to get the same saddle-to-bar reach.

A 54 cm frame also meets the top tube length for the 'Competitive Fit'. A 56 cm frame gets him into the 'French Fit' range.

philbob57

Sorry. I used CC's calculator over a year ago. I did not create an ID. I did not ask the site to save my data. When I clicked your link, I saw data, which I assumed was yours. Nope, it's mine. I am getting less and less happy with the Opera browser.

Maybe the shop would give you a real test ride. For the price of Domane, you ought to get more than a ride around the parking lot. Alternatively, perhaps they'd provide a good price an a frame of a different size, if you find the size they recommend to be uncomfortable.

But based on CC's numbers, your size is most likely to be 54, with 52 as the next best alternative, and 56 third. Based on Trek's height-only chart, it looks like it's a coin flip between 54 and 56, but it's based on measured height, and assumed numbers for other measurements.