Size Guide for new bike dilema on the cusp 54cm or 56cm

MrCubeLtd

Hello, I've finally raised the funds for a new road bike. But I have a dilema.
I have been to 3 different LBS stores and each one recommended a different size frame!
I am 5ft 10.5" (179cm) with approx 81 - 82cm inside leg.
I am looking at a Cannondale and according to their approx guide I should be a 56cm frame. I am on the cusp between a 54cm and a 56cm frame
I do have rather longer arms then average for someone my size.
Does anyone have any ideas please?

I have sat on a 56cm Cannondale and it did feel good - but bearing in mind I am only used to MTBs and never been on a road bike before. I'm thinking that the 54cm would be too small, even though I have a shorter inside leg my arms are long for my size. Hence the 56cm
Does this make sense?

pak-man

test rides are the best way to find out what feels best for you but...

i am 6'1", with longer than average arms and have a 56cm Cannondale CAAD9. Only when I recently upgraded (to a different brand but equiv to about a 58cm Cannondale) did I really appreciate how cramped I was on the 56cm. It wasn't enough to spoil my enjoyment but the slightly larger frame is much more comfortable for me. One of the first observations the new bike shop made when they saw the Cannondale was that it looked too small for me (this was after they'd sold me my new bike so it wasn't a sales ploy). On this basis, you might find you're better off with teh larger frame.

Anyway, just what works for me, test ride both sizes if you can and take it from there.

migrantwing

I had the same dilemma when looking at sizes for my bike before purchase. I was stuck in between a 53 and 56 frame (German sizing). I went with the smaller frame in the end. I see it as the best choice as you can always up the saddle height and mess around with stem angle and length. If the bike is slightly big for you, and you drop the seat right down, where can you go from there? Obviously, it all depends on the actual difference in size between the two bikes. All that I've mentioned above can go either way though, obviously. Just my personal opinion. I'd rather have a smaller bike that I can 'elongate' than a bigger bike that I have to 'shrink'.

But...as PAK-MAN says, he went for the larger frame. It's all relative. There is no right or wrong about it. A test ride will give you a better idea.

Hope this helps/makes sense.

Ringo 68

This is Wiggles take on thf you are between sizes.

What is your APE index?

http://www.wiggle.co.uk/h/option/bikesizeguide#Reach

MrCubeLtd

My local LBS won't let me take a test ride or measure me up as they think I am trying to get a size guide then buy elsewhere. I went back to Evans in Kingston and according to the bloke in the shop I am a 56cm. I also sat on a 54cm and the 56cm felt better. But still no test ride.

Cheers for the link regarding Wiggle.
My ape span is 72"- 73"
minus my height 5ft 10.5" - I have a positive ape span. So on that basis would it be ok with the 56cm bike?

Ringo 68

If it is any help I am identical in height to you with the same inside leg measurement.

I could have bought either a 56cm or 58cm Cube (Cubes tend to be on the small side) The 58cm felt just that little bit better was also nearest in size to my Medium Boardman.

Here is a link to the geometry of my Cube. Have a look how it compares to the bikes you are thinking about.

http://www.cube.eu/en/road/pro-comp/agree-gtc-pro/

I think the most important measurement is the 56cm Top Tube.

Gizmo_

I'm 5'9 and 79cm inside leg and ride a 54cm CAAD8 - but really, the only answer is to try both.

foo-fighter

My advice would be to get the one that feels right. Until 2 weeks ago i had a Specialized Allez in a 58cm frame, on paper at least it should of been the right size, the reality was very different. I was way to stretched out over the frame and could never get comfy as i was pulling my self off the widest part of the saddle to reach the bars. All the shops i went to before buying said bike were adamant i needed a 58, so i trusted their advice and it turned out to be wrong for me, as i have a short reach/torso for my height. Last week i bought myself a new Giant Defy 1 from another shop that i was unaware of when i bought the Specialized, great shop with great staff and advice! the sales guy initially suggested a large, but then gave me the best piece of advice that was so simple really. All he said was the measurements say you need a large, but try all the sizes we have, if it turns out the small is the one you feel best on then buy a small. I now have a Defy 1 in M/L and its so comfy and a joy to ride.

MrCubeLtd

I went with the 56cm in the end - just spent the last 1hr having a quick ride and making adjustments to the saddle and bars etc
First comments....
1, Weight difference compared to my MTB
2, Accerelation on the road compared to my MTB
3, Riding position is going to take a while to get used to
4, Absolutely enjoyed my 1st ride and if I am being honest I enjoyed it more then my mtb

Can I sustain both? Only time will tell. But mtb for me is mainly XC and not too technical. But my road bike even on slight hills was a breeze compared to my MTB and I had the biggest grin ever!
£500 lighter for a 2011 New old stock Cannondale Caad8 Sora (A good frame to build upon). Money well spent for my 1st road bike.

Now where did I put those lycra bib shorts?

Ringo 68

Nice one.

Does that mean you are going to change your user name to MrCannondaleLtd ?

MrCubeLtd

Good point. To be honest I hadn't given it much thought

But now that you mention it...

kleinstroker

Had a look at the Cube geometry, wondered why on earth a 56cm is a 56cm as nothing on it is 56cm?
I'm having this same problem by the way re: bike size, my current 56cm Klein feels a bit too stretched out, although it is the "correct" size for me (84cm inseam - 6ft tall) but after 3-4 hours in the saddle I get the worst neck ache, so have just finished building a new bike for myself which is a lot smaller.
I measured myself 3 times and put everything into a few different calculators for frame fit and they all recommended I ride a 54.5cm frame with 55.5 top tube. I went for a ride yesterday on my new bike with 53.5 top tube and 110mm stem, and for the first 20 minutes I was convinced it was too small for me, but 30 miles later and I really like the fit. I will need a longer stem, 130mm, to adjust reach to hoods but all in all this frame just feels better even though it's officially a 52cm!!
It's confusing to say the least.

smidsy

kleinstroker wrote:

Had a look at the Cube geometry, wondered why on earth a 56cm is a 56cm as nothing on it is 56cm? It's confusing to say the least.

Manufacturers often try to relate their frames to traditional sizes in an attempt to give you parity - in reality this does not work as there are so many different variables between manufacturers, geometries, top tube styles etc. that what you end up with is one size fits no-one.

Basically there is no single measurement method and the only way is to get on them and see what works for you.

A 54 in a Cube will likely fit totally different to a 54 Cannondale for example.