Advice on size please ? Giant Propel Advanced 2017

bilabonic
bilabonic Posts: 299
edited May 2019 in Road buying advice
Hi All

Hi guys,

Looking to purchase a Giant Propel Advance 2017 (delivered so can not test run). Medium ST=52cm, Stack=55.3cm

I'm 5'8" and 31.5 inside leg. (wear a 32" reg jeans..lol)

I have not had a road bike for a few years and then simply went on seat tube length, i was always 54cm.

These new aero bikes have a new geometry and use stack height (which comes in as bigger)..

I was confused by this as as i was chatting to a mate with a had a Cube Agree and he stated it was Large, so i asked him to measure the tube length and it was 52cm!! He sent me a pic of this and it had 56cm written on it??

Looking at the chart below i am on the edge of S or M..

https://www.giant-bicycles.com/int/prop ... ced-0-2017

Has anyone got one to hand or one with similar geometry to comment

Cheers
Specialized Epic FSR Carbon Comp

Comments

  • StillGoing
    StillGoing Posts: 5,211
    If you're between sizes, go for the smaller size and adapt with stem lengths and set back.
    I ride a bike. Doesn't make me green or a tree hugger. I drive a car too.
  • -Dash
    -Dash Posts: 179
    Yep. Older Cube sizing was silly. 56cm more like a 52cm from any other brand. I wouldn't call the 56cm Cube Agree a "Large" though, there are far bigger Cubes available. Think they go up to "62".

    Any Giant stores near you? They usually have a demo fleet, the current Propel would be very similar geometry.
  • matt_n-2
    matt_n-2 Posts: 581
    Cube are a bit weird but when you grasp it it’s quite simple, they are sloping frames but size by virtual seat tube as if it were a horizontal top tube; centre B.B. to virtual top of seat tube.

    Their Large or 56cm means 56cm effective seat tube length, which is actually 52cm and has a 56cm ctc top tube. Their sizing is actually very similar to Colnago but does take some thought.

    With Giant I find I’m between sizes M and M/L.
    Colnago Master Olympic
    Colnago CLX 3.0
    Colnago Dream
    Giant Trinity Advanced
    Italian steel winter hack
  • N0bodyOfTheGoat
    N0bodyOfTheGoat Posts: 5,834
    I'm 178cm tall and cycling inseam of ~83cm, my Cube is a 58cm frame with a 54cm seat tube. Stack 610mm and reach 388mm.
    https://www.cube.eu/uk/products/road-ra ... hred-2016/

    If I was buying a Propel, going on stack/reach, I would be either M or ML. Given a Propel is all about aero, M with a +10mm stem would be better, if my back could cope. It would also give fractionally more seat post, on my Cube I use ~73cm BB to saddle top.
    ================
    2020 Voodoo Marasa
    2017 Cube Attain GTC Pro Disc 2016
    2016 Voodoo Wazoo
  • zefs
    zefs Posts: 484
    You can ride both, the S has smaller cranks which would be more suitable for your inseam. Then the M has 2cm bigger stack which would be a better choice if you are not flexible enough and need a higher position (although you could use spacers on S size, too if needed) but I am guessing that's not an issue since you are going for an aero bike.
  • -Dash
    -Dash Posts: 179
    zefs wrote:
    cranks which would be more suitable for your inseam.
    I'm curious about this. Can you elaborate?
  • shirley_basso
    shirley_basso Posts: 6,195
    Effective Top Tube and Head Tube has always been a more effective measurement for me. About 57cm and 16cm respectively and I am 6ft on the nose and 32in inseam.

    Generally speaking the company size guides work well if you have normal proportions. Giant are pretty well represented through their dealer network - can't you sit on one?
  • sithebike
    sithebike Posts: 213
    I am 5ft 8 and ride a small Propel advance.

    Hopefully that helps.
  • zefs
    zefs Posts: 484
    -Dash wrote:
    I'm curious about this. Can you elaborate?

    170mm cranks of the S Propel are a better choice bio mechanically for his inseam than 172.5mm
    It might be a detail but it makes a difference on pedaling motion.
  • -Dash
    -Dash Posts: 179
    zefs wrote:
    -Dash wrote:
    I'm curious about this. Can you elaborate?

    170mm cranks of the S Propel are a better choice bio mechanically for his inseam than 172.5mm
    It might be a detail but it makes a difference on pedaling motion.
    Do you have a source for this? Genuinely interested. My inseam is shorter and I run 172.5.
  • zefs
    zefs Posts: 484
    -Dash wrote:
    zefs wrote:
    -Dash wrote:
    I'm curious about this. Can you elaborate?

    170mm cranks of the S Propel are a better choice bio mechanically for his inseam than 172.5mm
    It might be a detail but it makes a difference on pedaling motion.
    Do you have a source for this? Genuinely interested. My inseam is shorter and I run 172.5.

    https://bikedynamics.co.uk/FitGuidecranks.htm

    You can run different size cranks because it doesn't only depend on inseam but also leg proportions, flexibility etc. but yeah all those parameters are only of interest if your saddle position/fit is correct so don't want to get too off topic.
    I have tried 165 to 175 crank lengths and I think the guidelines on the link above are correct (for my inseam atleast) regarding pedaling motion/feel.

    Power wise shouldn't matter much, but I think having the correct size helps with the overall feel so pedaling motion would be smoother.