Sizing Cervelo R5 help

Hi there,

I think of pulling the trigger on a Cervelo R5 - i think I can get a great deal.
I currently ride a TCR Advanced 2 in size M.
I’m 5’10” tall/short and have a inseam of 32”.

I was thinking 54cm. Stack height of the Cervelo is a bit higher, but reach 3mm shorter. What else should I be worried about?
I have no local dealer who carries the R5…


Unless you are running the TCR slammed, you should be able to achieve the same effective stack on the R5 by adjusting spacers. I’d suggest 3mm in reach could be achieved by adjusting saddle fire/aft.

FYI I’m almost exactly your size (177cm/81cm inseam), used to ride a medium TCR, and was fitted for a size 54 R3 (even though I decided to buy something else in the end).

In terms of what else to worry about, I’d be a little cautious about the bb in the Cervelo. If it’s a new bike then you should be covered, but bear in mind the hassle of getting it warrantied if there’s no local dealer.

Anybody else with an R5 who would be willing to share his body size\bike size?

I don’t have an R3 but another Cervelo, the ancient SLC-SL. I don’t think their geometries have changed all that much since then. I’m 178 cm and my inseam is 83 cm if that is of any help.

I remember having the same issues as you regarding size, chosing between a 56 or 54. I finally decided on the 54 as it is the “pro”- way😜 seriously a to large frame is always to large and it is easy to just raise the saddle and fit a slightly longer stem on a small frame without it looking wierd.
I have long femurs so my saddle is far back. I used to have 120 mm stem but nowadays I use a 105 mm long. My handlebar is Richey SL ergo bend so it it low in the drops but not extreme. I’m 56 and not as flexible as I used to be.

I am 6ft and ride a 56cm. Great bike and fits well. Stable and fast. Lots of adjustment options.

I’m 178cm with 84cm inseam.
I now ride a 2019 Scott Foil, but before that I rode a Cervelo R5, slammed all the way with a 110mm stem in size 54.
I generally prefer the smaller size and like to adjust with the stem.

thanks guys.
I took some body measurements today and actually, I’m only 5’9,25"/176cm. Inseam 32"/81.5cm.
I would assume 56cm is too large?

I am 5’11 with a shorter 31” inseam. I have a 54” 2017 R3. It’s the right size for me for a road bike. It is a more aggressive set up and I would have a harder time dialing in a position in a 56”. Based on your measurements, I think 54” is the way to go. Good luck.

As I said above, I’m 177/81 - literally almost exactly your size. 54 was bang on for me (in an R3). 56 would definitely have been too big (standover alone would have been an issue).

Hi, based on your description, a 54 cm would be the right size. I have been riding a 2018/2019 R5 in 56 cm. I am 6’0", 32/33 inseam. I rode a 56 R3 (2014) before. The 56 is perfect for me. I run a 110 cm stem, and the zero offset seatpost. The stack is lower than the R3 (2014) I used to ride, but there’s also slightly more tire clearance on the R5, so the fork might be a few mm higher (I’m not sure about that). I have 20 mm of spacers under the stem.

Also building a 2019/2020 R5 for my wife. She’s 5’7", former pro racer, long legs/femur with ~31/32 inch inseam. She went with the 51 cm, but to get the stack she wants, needs more spacers (25-30 mm), and will probably run a 120 mm stem (angled up) and the 25 mm offset seatpost to make the reach long enough for her (the size 51 comes with a zero offset seatpost, while the size 54 and higher comes with the 25mm offset seatpost).

Anyway, the R5 is awesome – really snappy acceleration and stiffness in the BB, along with comfort on longer rides (after 2,000 miles on mine since since building it earlier this year). Feels much more responsive than my 2014 R3. Happy to post a photo or answer other setup questions.

Thanks for your reply. I’d love to see some pictures. I was wondering about the look of the spacers anyways as the stem of the R5 is rather chunky and I feel it looks somewhat “interesting” if there are too many spacers…

Why would one do this? Isn’t the saddle position dictated by the BB?

5’8", 30 in inseam, 51 cm R5

Well let’s say the reach or effective TT of the bike is length X. The person wants a riding position that is very close to X, but a few mm shorter or longer. As 2-3mm variations in stem length are fairly hard to achieve, and we’re not in the realms of custom frame geometry, the easiest way to do this is probably to move the saddle slightly back or forward on its rails. Note - slightly. I’m not talking about guys who slam it all the way back or forward.

Edit - also consider a seatpost with different amounts of offset.

I understand the how, kind of question the why if the goal is to be in the same position is all. Wouldn’t it be more important to keep the lower body the same and stretch/shrink the upper body the little bit?

I’ve certainly felt the difference between reaching too far and not but would think changing the pedal stroke has more consequences.