ctcycler

I am 5'6" and have long legs. I am currently riding a 54cm Scott, with a short stem. Ciould've gone with a 52 and a longer stem, but liked the 54cm

ob1left

I'm between 5'7 and 5'8 and ride a 52

tagaproject6

I ride a 54.

Elkhound

You might inquire at the Hobbiton & Bywater Cyclery, right across from the Green Dragon.

Bostic

5' 7". Either 52 or 53.
Pedal Force RS 53cm, 53.5cm top tube, 14.5cm head tube, 10cm stem
Jamis Eclipse 53cm, 54cm top tube, 13.5cm head tube, 90cm stem
Specialized Steel Allez 52cm 53.7cm top tube, 9.7cm head tube, 10cm stem
Fuso steel 53cm, 53cm top tube, ? head tube, 9cm quill stem

Most 54cm bikes have longer top tubes and will come with 172.5 cranks which are not my ideal.

Bobsled

Seems to be all over the map, I'm 5'9" w/ 31.5' inseam and I ride a 55cm and a 56cm.

terribletiger

ride a 54. i used to ride a 54 and i switched to a 52 and it didnt feel that great.

StalkerZERO

I ride a 52" 2005 specialized roubaix. And it has served me well. But even though I love my little bikey I'm afraid I'm going to have to retire him soon.
I expect to be upgrading to a new roubaix frame and it will most likely be a size 52 as well.
I'm 5' 8" by the way.

gundom66

I'm 5'9" with a 30 inseam. Went to Trek and sat on a 5.2 at 56 and at first, I felt a bit stretched out. Tried a 54 and it was fine. Tried a Medium on a Giant Advanced Defy 2 since it's supposed to fit my size. Granted it had a 100mm Stem, that damn bike was too much of a stretch for me. Tried a Roubaix on both 54 and 56 didn't feel right. Those bikes are supposed to be a good comfort bike, but it didn't feel right for me. Tried a 55 Infinito and that was dead on! The RS on a 54 was dead on too! Went back to Trek to actually test ride a 56, and that time around, it was darn fine and comparable to the Infinito. Though power pedalling was a bit twitchy on the handle bars... which didn't occur when I was on the Infinito nor the RS. I will try the 54 on the 5.2 this weekend when I pick up my MTB and see if there is a difference.

What I'm trying to say is that it doesn't matter what the LBS proposes, whether it be a 52, 54, or 56. It depends what suits you best on whatever brand of bike you sit on.

gospastic

I'm 5'7", and I feel best on a 53cm top tube.

longbeachgary

I'm 5 ' 7 and ride a 55 Merckx. I hate feeling cramped when I ride so that's why the 55.

mconlonx

5'7", ride a 53cm IRO Rob Roy, been told I'd fit a 52cm Trek H2 fit by others who have years of fitting experience. Most people will fit a couple sizes with various adjustments. Some people are lucky, and some brand makes a bike the perfect size for them. The rest of us make compromises.

If you're looking at higher end bikes, you could certainly ask a shop to size you to a couple bike sizes on a trainer or test rides to figure out which size will be better out of the box, then pay for a professional fitting for details like stem length, bar width, etc.

Unagidon

A bike with a reach of approx. 375 to 385mm.

Looking at Trek, the 52cm Madone comes with eff tt of 53.4cm with 74.2 degree seat tube angle. If seat tube angle is steeper, you'd probably want something with shorter reach, and vice versa.

Also look at the head tube length to get a ballpark stack. For less drop, maybe you can even go 54cm on certain bikes, and just get a shorter stem.

sharp.point

I'm between 5'6 - 5'7, 28.5 inseam; ride a 52, 170cm crank. When I first started out, I have shorter stem with large angle; now using 90cm - 6 degrees.

charliekeri

any frame with about a 54.5 top tube. Usually that is a 54 or 55 frame. Any frame smaller has too small a headtube and drops me too far down in front. Any frame larger stretches me out too much.

That is just a my body thing, you got a your body thing to deal with...

bhop

5'7" here.. 53cm Bianchi Via Nirone. My fixed is a 50cm, both bikes fit the same though.. *shrug

neneboricua

I'm 5'8". Ride a Fuji Team Pro (race geometry) which is a 52cm but with a stem slightly angled up (slowly moving spacers down as I get more flexible).

I've also got a Novara Divano as a winter training bike and that's a 54cm.

I was professionally fitted to the Fuji when I bought the bike. Later when I got the Novara, the LBS just matched the same fit to the Novara since it was working for me. The two bikes feel almost identical now (in terms of positioning and such). The 54cm does have a taller head tube so they had to flip the stem to reproduce the same saddle-to-bar drop (about 4-5cm for me currently) and reach proportions. But in the end, they feel identical (although they ride very differently).

neneboricua

Zokya

5'8" (173cm) with 30.7in (78.5cm) inseam. Short legs / Longer Torso.

Frame sizing between different brands are all over the place so you need to look at the geometry.
I ride a 53cm with a 53.5cm effective top tube.

I (think) I'm about to get a Cannondale in a size 52 with a 53.5cm effective top tube and run a 100mm or 110mm stem.

If you take a look at Cannondale's geometry for SuperSix / CAAD you'll see there's only a 1mm difference in "reach" between at 52 and a 54 so either could work depending on your drop preference / inseam. I have shorter legs so I'd be looking at the smaller size but could probably make either work for me.

kabex

1.72m (5'8?) 52cm

sci_femme

5'7"" leggy girl and I ride 54 Tricross. I have been told that in roadie sizes it is more like 5'6".

I guess it is all depends on your proportions.

SF

Hulley

5'8" on a good day and I ride a 2011 Scott CR1 in a small (52). I road many bikes before buying this one 5 weeks ago and the 54s seem to be a little strech for me.

learnmedia

A hair under 5'9". 30 inch inseam. Ride a 54 Fuji Team. 110mm stem. 170mm cranks.

JoelS

5'7" and a 54 cm TT

Jandro 

5'8 here with ~30-31" inseam. I rode a 54 Scott Speedster S40 for ~6 months and it was comfortable, but I couldn't get the seat-to-bar drop that I wanted. Just picked up a 52cm (53.5cm top tube) Specialized Allez Elite and it feels so much better.

My advise, like others on this thread, would be to go to a few LBS and just start trying the models you like in both sizes. Find the one that feels/fits the best and roll with it. A 52cm in one brand is a 53 or 54cm in another so you really just have to try them out.

My $0.02

Gios78

5'7 with approx 29.5 to 30 inch inseam. I ride a small BMC Streetfire with a 52.8 ett and a 120 stem and no spacers. I do use a setback seat post. I could probably go one size smaller or larger depending on what handlebars and how much drop I wanted.