54 or 56 bmc team machine

But that’s silly, if you got
But that’s silly, if you got a full on race bike you would get used to it and become more flexible through riding it. I have a sit up and beg ladies bike which is exceedingly comfortable, but that doesn’t mean my race bike should be set up the same.

Leg to torso ratio along with
Leg to torso ratio along with your total height is of utmost importance. I have my own fitting method that suits 98% of riders.

If you’ve long legs and short torso you need: a smaller frame for a top tube that’s short enough to use a longer stem.

If you’ve short legs and long torso you need: a smaller frame for a head tube short enough to get decent aero position with your lower saddle relative to the bars.

If you’re around 50/50 leg to torso you need: a smaller frame because it looks more pro.

It’s still a bit over complicated I think. trying to streamline the method, always.

+1 for going for the smaller
+1 for going for the smaller frame as you can always add spacers to the stem and adjust the angle of your handlebars/saddle but it’s hard to cut back the top tube length if over time you develop upper back/neck pain from being stretched too far forward. Not saying that there aren’t shops that can competently cut your carbon top tube down for a custom fit but it would void your warranty.

FWIW, I put in my measurements on the CC bike fit guide (love at company and buy stuff from them that my LBS doesn’t stock–overall my LBS has better prices cuz they’re also an online retailer too). They recommended the Eddy Merckx fit, less aggressive cockpit than the competitive racing fit used by the pros, which means going for a larger frame with a less acute seat tube angle for less back and neck extension when you’re in the drops. This is of course, not what my current bike is at all. My Pinarello has a 46 cm seat tube length with a 51.5 cm top tube and while the cockpit is pretty aero and aggressive compared to many bikes, my old Kestrel was a 52 (hubby said it was 52 not 48) and while that would fall in line with CC’s fit recommendations, the Kestrel was nowhere near as comfortable as the Pinarello and unpleasant beyond 70 miles.

Actual Inseam 31.5 In
Trunk 17.25 In
Forearm 13 In
Arm 25.75 In
Thigh 22 In
Lower Leg 19.5 In
Sternal Notch 52.5 In
Total Height 64 In

Top Tube Length 49 – 49.4 Cm
Seat Tube Range CC 53 – 53.5 Cm
Seat Tube Range CT 54.6 – 55.1 Cm
Stem Length 8.6 – 9.2 Cm
BB Saddle Position 68.3 – 70.3 Cm
Saddle Handlebar 46.9 – 47.5 Cm
Saddle Setback 5.7 – 6.1 Cm
Seatpost Type Not Setback

So, unless the 56 is massively more comfortable to ride than the 54 I’d personally opt for the 54 as a lot of people end up fine tuning their fit over time (riding style changes, you settle into the bike). That being said, you know your body and riding style best and need to do what you feel comfortable with 🙂

Scoob_84 wrote:I’ve been was

Scoob_84 wrote:

I’ve been was told that its best to go for the smaller size if you sit somewhere between two, as you can always knock the seat back and increase the stem length. And if that doesn’t convince you, most pro’s ride on undersized bikes as well!! (as if that helps)

I’d also head the advice of others by getting fitted. When i bought my supersix, I first went to evans to try the 54 and 56 frames. But the stems were stacked so high on both bikes the test rides were almost meaningless. The 56 felt like i was riding a boris bike so I ended up going for a 54. But now even over a year later doubts sometimes creep in over whether i bought the right bike! With the kind of money your about to spunk, you really don’t want those doubts!

Fitting or buying from a good bike shop with a decent fitting service is expensive and I’m all aware of the temptation just to go off your own judgement/sizing charts and hope you get it 90% right!

That’s my advice as well and I confess to having learned that approach way back in the 70s. Basically you go with the smallest frame you can reasonable get away with. Why? Well it’s common sense really.

Smaller is stiffer
Smaller is lighter
Smaller is more responsive

I’m almost the same size as
I’m almost the same size as you, and was having a tough time deciding between the 54 & 56 cm Cannondale Synapse. I gave both a good test ride, because I’m lucky enough to have a lovely LBS, and I felt a bit happier on the 54. I felt like a bit more nimble on it than the 56, which is what swung it for me.

I could have lived with 56 very happily, but the 54 was a bit better. Of course, Cannondale and BMC sizing differences could totally change that.

True, unfortunately frame
True, unfortunately frame sizes vary by brand. You’d think that just by going by the geometry specs (seat tube, top tube length, …) you’d be able to make sense switching brands but even though the geometry chart said the top tube on my Pinarello Marvel is supposed to be 51.5 for a 46.5 cm seat tube, the actual measurement in the shop was a centimeter shorter so I went from a 48 Kestrel Talon to 46.5 in Pinarello. Same thing with the hubby, he went from a 58 in his Masi 3VC Volumetrica to a 56 Pinarello Paris.

Fit seems to be different among bike fitters, a lot of people have told me that it’s better to have a slightly smaller frame than one that’s too big as when you’re stretched out too far not only can you develop upper back/neck pain but you end up fighting more for control (ie cross winds, choppy terrain, cornering …) than when you’re more centered. Of course, what is stretched too far for one person may be perfectly comfortable for someone else. When we bought our bikes the LBS let us take multiple hour+ test rides (the hubby did 6 or 7) to make sure that we felt comfortable with the handling and fit. Hopefully they’ll let you do the same at Evan’s and perhaps you could take routes that you’re used to (ones that tested how comfortable, ergonometry and handling-wise, you felt on your Scott) to help make an easier comparison. Too bad the link above sends you to the main page. Sounds like it would be a nice bike (I had Dura-Ace on my old Kestrel and it was very clean shifting although a difficult comparison to the Ultegra on my Pinarello which is much smoother but also a 7 year tech advantage).