Hello
I have a problem with choosing correct size of CAAD10 frame.I put my measurements in 2 calculators (pedal force and competitive cyclist) first one recommends 53cm top tube and second one 55cm.
I'm 5'10" (178cm) height, 32" (81.5cm) inseam.Im very flexible with strong core and usually riding aggressive.
I'm kinda torn between 52 (53.5 top tube c-c) and 54(54.5 top tube c-c) CAAD10 frame size.
I will try to get on both to check it out but what would You recommend ?
Thanks for any advice.

First look at the seat tube angles of the two frames. If they aren't the same, then you have to correct one of the top tube lengths to make them comparable. The 52 has a 1/2 degree steeper seat tube angle, so it's top tube is really 0.5 cm longer in practice than listed as compared to the 54. That is because you have to push the saddle back that much to get the same position over the bottom bracket. So there is almost no difference between the two top tubes in effect on reach, just 0.5 cm. If I were you I would make my decision based on how much seat post you like exposed and on the heat tube lengths. If you don't want much saddle to bar drop, pick the larger frame. If you want a more aggressive position, pick the smaller frame.

All the sizes that you mention, for someone who is 5'10", are really too short. I would highly recommend that you check out some bikes with more like 56 to 56.5 cm top tubes. I am only 5'6" and ride bikes with 52 -54 top tubes. Look at Peter Sagan, he's about 5'10" and his Specialized has a 56cm top tube and a 140cm stem.

52 is too small for even an uber flexible rider.
54 is very racy...would need longer stem...big saddle to bar drop.
56 is a more standard size for your dimensions with more conventional saddle to bar drop.

Lance is exactly your size and rode a Trek 58cm throughout his career...considered a large bike for his body size and proportions.

Yep, I would've said 54-56, definitley not 52 - but that's just me and others prefer the crazy-small frame with longer seatposts / stems....

I'm just under 5'11 and had a CAAD9 in 54 that fit great. I had a CAAD10 in 56 that worked but always felt a little big.

Me my height is 5,7" amd my inseam is 32". My bikes is 56cm 57cm and 58cm. In the 56cm ct the tt is 56cm. And in 58cm the tt is 56cm. In the ct 57cm the tt is 57cm. that bikes is okay for my height or is tto big for me?

I'm 5'10, 32" leg and ride a 54cm CAAD10 with a 120mm stem and 15-20mm of spacers under. Whenever I rode with the stock stem slammed, my knees would hit the end-caps of the drop bars when out of the saddle.

I don't think my position is super aggressive, but I can get a flat back in the drops when I want to.

I am 5'10" pants leg length 30"
I own both 56 and 54 caad 10s
Got the 56(2012)first and it was a tad too big, had to go to shorter stem.
The 54(2015) is just about right for me, I suspect the 52 would be a bit small.

52 seems small.

A 52cm caad 10 should measure more like a 54 in top tube. Those bikes are long and low to the max.

Peter Sagan is just over 6' and has short legs and long torso for his height.

@OP, those calculators are for getting a general idea of fit before getting the first bike. Do you already have a bike you're comfortable on? What is it and how is it set up?

I am 5'10 with a 33" cycling inseam. I've owned a 52cm CAAD10 that's fully slammed. It felt great, but would tire my back over long distances.

If I were to do longer rides, I'd pick the 54cm CAAD10 for the more upright seating. Both work great, depending on how aero you want to be.

Don't listen to those guys saying 52-54cm is too small. If you have longer legs and a shorter torso like me, you'd fit much better on a smaller bike. If you have a longer torso with shorter legs, a larger bike would fit better. For example, the reach to the handlebars on a 56cm CAAD10s is waaaay too far for me.

It's really just comes down to personal preference.

Thank You very much for answers.I read every one of them,i wont lie i'm a little biased towards smaller 52 frame.
My current bike have around 54-54.5cm top tube and 9 cm seat to handlebar drop and i find it very comfortable.
I prefer smaller bikes so i think 56 is out of question.
So its between 52 and 54 frame.
Thanks again,will try to get on both of them or something similiar today.

if you look at caad 12s remember they measure square, so a 56 fits like a 54 caad 10, a 54 fits like a 52. It's not confusing in the least.

What gives you that idea? The actual C-T measurements have changed on CAAD 12, but the same nominal size still means the same fit. So a 54 CAAD 12 has a 57 cm seat tube, but stack and reach are almost the same as a 54 CAAD 10.

Why not find a shop that keeps a few sizes in stock, and take one for a test ride? Putting one on a stationary trainer would be helpful determining fit.

My caad is 48 Amira is 51 both same riding position. I Def think smaller size is more fun and better handling.

Read the geometry chart, the bike is definitely off a size compared to the caad 10.

Reading the geometry charts, here is how stack and reach compare:

- - - - - - - 54 - - - - 56 - -
CAAD 10 - 54.6/38.3 - 56.0/39.4
CAAD 12 - 55.1/38.7 - 56.7/39.3


So not only does a CAAD 12 in size 56 not fit like CAAD 10 size 54, it actually fits a little larger than a CAAD 10 56. You are way off in claiming that CAAD 12 56 = CAAD 10 54.

FWIW, I'm 5'6" with 29-30 inseam. My 52 CAAD 10 seems fine.

I second going to your local Cannondale shop and actually trying them.

(but you're gonna end up on a 54)

Not 52... my thought would be a 56 for maximum comfort or the 54 if you want a bike that accommodates a more aggressive riding position and has the shorter, more nimble wheelbase.

What measurement are you calling 54/56? The size sticker on my bike said 56, but it had a 57.5 effective top tube. There is an extra row on the chart called measured size (referring to the size sticker on the bike) that doesn't read inline with the rest of the measurements for a size. Cannondale geometry charts for caad8/10 and the last version of the evo are unnecessarily hard to read for that reason, IMO.

Those are the measurements for the nominal sizes 54 and 56. It seems to me that you had a mis-marked frame. Top tube of 57.5 cm has meant nominal size 58 for Cannondale for the last decade at least - just check the geometry charts.

Personally, I find the Cannondale geometry charts to be exceptionally clear and informative, but I guess the abundance of information can make them confusing for those who aren't as interested in every little measurement there is.