Sizing nightmare

Easyrider642

I'm having a bit of a nightmare when it comes to sizing. Have researched for a while now and finally came to the crunch to buying a bike and was out of stock, and so was the next one and the next and the next.

I've got my eyes on a Focus Cayo Al 105 but the sizing is slightly different to what I have seen. I'm 5ft 11 with an inseam of 33". Compared with the geometry of a 56 cube attain (560 TT and 182 HT) the Focus in a 54 has a slightly shorter top tube (552 TT and 145HT) but is more aggressive. Can anyone give me some advice as to whether the 54 or 57 would suit better which is 569 TT and 165 HT

Going to try one in both sizes in a week or so if possible.

mcstumpy

If it helps, I’m 5 10 with shorter legs and a longer back, I have a Cayo Evo in Large (57) and for me size is bang on.

pilot_pete

It's a bit hard to say what will be best for you over the internet - there are too many variables. Ideally you need to be set up on the bike (or a fitting jig) to find your comfortable, ideal position. This can then be measured and different frames can be assessed to get the closest fit.

Stack and reach are useful for this because you can't compare one frame to another just by looking at top tube length or seat tube length. Each frame will have different geometry including things like head tube length and head/seat tube angles, which will dramatically alter your final position on the bike, despite things like top/ seat tube being similar.

Even someone saying 'I'm 5' 11" and ride xxx doesn't necessarily transfer due to individual differing proportions. I am exactly that height and ride a 55cm TT in a Pinarello, but size 52s in a Colnago, which is as close to a 55cm TT as to not make a difference. However, I used stack and reach to work out how close they would be and fitted a slightly shorter reach compact bar to get my overall position virtually the same.

Hope this helps.

PP

dannbodge

As above.

Everyone fits differently and I wouldn't just look at seat tube lengths and top tubes. The way they interface with the other tubes will change the feel and fit of the bike.

Ideally you want to find the stack and reach of the bike that fits, and then find another that has the same/similar.
Both my bikes have a similar stack/reach ratio (Tarmac is 1.40 and Allez is 1.45) so by adding/removing spacers and changing stems I can get the fit to be almost identical on both bikes.

I recently used this website: http://www.bikegeo.net/ (along with the bike geometry sheets: https://www.geometrygeeks.bike/) to work out how I can make the Allez have the same position as the Tarmac (Which I had a bike fit on)

N0bodyOfTheGoat

Stack and reach should give you a decent ballpark of what size you want.

I'm 5'10 with ~32.5" cycling inseam, I'm all torso and stumps for legs, when I buy trousers I need ~29/30" inside leg.

My Cube is the 58cm, with 610mm stack and 389mm reach. Stem in negative position, pointing slightly down, flipping it would reduce reach to the bars by ~2cm IIRC.

The 56cm might have fitted me ok, with 591mm stack and 385mm reach, but given my 9-year history of damaged weak lower back muscles I wanted the taller front end.