# BMC Promachine SLC01 sizing help please



## zoothornrollo

Wondering if anyone can help:

I plugged my measurements into the Competitive Cyclist fit calculator and got the following recommended ranges (from their raciest fit at one end to what they call a 'French fit', i.e., more relaxed, at the other):

Seat tube cc: 49.2-52.6
TT: 53.3-54.5

SLC01 sizes come out as follows:

49cm frame
ST: 51.1
TT: 53.0

51cm
ST: 52.8
TT: 54.0

In other words the 49cm is great for seat tube height but possibly a bit short on the top tube.
Are these discrepancies worth worrying about - i.e., it will be easy to get a good fit on either frame?
In which case, does anyone know whether going one way would be preferable to the other - ie. one would presumably involve raising the saddle, whereas .... ?

One racing cyclist mate of mine says if in doubt go for the smaller frame. But then I've also heard that the top tube length is the most important thing to get right (i.e., the 51) ...

The 51cm felt ok when I rode it but I think test rides are of limited use as they are always going to adjust the seat and bars to be comfortable and how can you tell what is right in 15 mins' riding?

Thanks


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## holy cromoly

Top tube measurement is important.

Will this be your first road bike?


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## zoothornrollo

holy cromoly said:


> Top tube measurement is important.
> 
> Will this be your first road bike?


No. Currently have a Spesh Allez 54cm.
Which is OK but the reach I think is too long - I get v stiff neck and upper back from long rides.
Probably something that stem adjustment could cure a bit, but that 54.8 TT is deffo too long.


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## ultraman6970

I don't trust the tables from CC because sometimes it throw you off big time. I have that problem for example.

As for the bike you have, the problems you have could be anything from a saddle in the wrong position to a frame too long. sincerely w/o seeing you is hard to tell. We dont even know how tall you are or even your inseam measure just to have an idea. That said, if your spech is set up wrong then you will have the same problems but now in a sweeter bike. 

This is what i would do just because is pretty accurate ok? Go to the BMC website, find the bike u want and look at the geometry tables, there is a column with rider height, look at there, is pretty accurate.

For the record there is a big difference between the allez and the promachine. Starting with the front tube, if you use kind;a stand up position keep the allez, the BMC doesnt deserve that set up hehehe

This is where u have to look, good luck!

BMC swiss cycling technology - Promachine SLC01 Standard - Road - BMC, Bicycles, Bikes, BMC Cycles, BMC Mountainbike, BMC Cycle


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## holy cromoly

zoothornrollo said:


> No. Currently have a Spesh Allez 54cm.
> Which is OK but the reach I think is too long - I get v stiff neck and upper back from long rides.
> Probably something that stem adjustment could cure a bit, but that 54.8 TT is deffo too long.


I am 5'10 and ride a 54cm BMC SR02 (55cm toptube).
I used to ride a 54cm Specialized Tricross, (54.5 toptube).

So I definitely think you're right about your 54 Allez being to long on the toptube.


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## zoothornrollo

ultraman6970 said:


> I don't trust the tables from CC because sometimes it throw you off big time. I have that problem for example.
> 
> As for the bike you have, the problems you have could be anything from a saddle in the wrong position to a frame too long. sincerely w/o seeing you is hard to tell. We dont even know how tall you are or even your inseam measure just to have an idea. That said, if your spech is set up wrong then you will have the same problems but now in a sweeter bike.
> 
> This is what i would do just because is pretty accurate ok? Go to the BMC website, find the bike u want and look at the geometry tables, there is a column with rider height, look at there, is pretty accurate.
> 
> For the record there is a big difference between the allez and the promachine. Starting with the front tube, if you use kind;a stand up position keep the allez, the BMC doesnt deserve that set up hehehe
> 
> This is where u have to look, good luck!
> 
> BMC swiss cycling technology - Promachine SLC01 Standard - Road - BMC, Bicycles, Bikes, BMC Cycles, BMC Mountainbike, BMC Cycle


Thanks.

The rider height puts me with the 49cm - just. I have now sat on the 49 - though not ridden it, as it was not properly built - and according to the shop staff, it looks like a better fit.

Measurements as follows:

Inseam: 76.5
Trunk: 62
Forearm:33.5
Arm: 61
Thigh: 55
Lower Leg: 51.5
Sternal Notch: 137
Total Body Height: 168


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## holy cromoly

*Sizing Chart for Pro Machine 2010*

Here is the geometry and sizing chart for the 2010 Pro Machine.

At 168 in height, you're on the cusp of the 49 and 51 as you know.

Being that the Allez 54 feels a bit long and the BMC 51cm is close to it in top tube length, seems like the 49 maybe be the way to go. But going with a smaller size also means the head tube will be shorter and may result in longer reach depending on your stem setup and may need to have some rise on it.

But what is your stem length on the Allez right now? And what handlebars are you running?

I am not a fan of riding stretched out Pro Tour style, so I prefer a shorter top tube for my long distance non-racing riding. I run an FSA Omega Compact handlebar. The reach for the hoods and drops is shorter and you can get a more comfortable ride reach wise.

The FSA bars make a huge difference in cockpit feel reach wise.


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