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Could be wrong, but all carbon must be laid up by hand.

Looks are built in France. Really nice frame if you are concidering it. Watch out, they have longish top tubes like Trek, so don't buy one based on the seat tube length. The size 53, which I would normally not concider, has a virtual tt of 54.5 cm.
 

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TTs are NOT long..

I don't know where you guys get his idea, unless you don't understand frame sizing. LOOK measures c-c so a 53cm would compare to a 55cm in brands that measure c-t or a 56cm in a Trek.

A 56cm Trek has a 56.1cm TT and a 73.5 degree STA. Compared to a 53cm LOOK 565 which has a 54.5cm TT and 73.75 STA. Correcting for the small difference in the STA, the LOOK still has a 1.3cm shorter head tube.

The reach on a 555 is even shorter, that's why I own a 461 that has the same reach and a 381 that's a touch shorter in reach.
 

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C-40 said:
I don't know where you guys get his idea, unless you don't understand frame sizing. LOOK measures c-c so a 53cm would compare to a 55cm in brands that measure c-t or a 56cm in a Trek.
The point is that if you normally "think" you ride a 55 or 56, don't automatically reach for a 55 in a Look frame. Nothing terribly complicated about it.
 

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I agree...

AlexCad5 said:
The point is that if you normally "think" you ride a 55 or 56, don't automatically reach for a 55 in a Look frame. Nothing terribly complicated about it.
That's why your comparison is flawed. Trek and Fuji are two brands that use an odd-ball measuring system. Most other either use c-c or c-t. Their "56cm" frames are actually much smaller, either 54cm c-t or around 52.5cm c-c. When talking frame size, you have to specify the measuring standard.

Another common mistake is ignoring the seat tube angle. A frame with a 72.5 STA with a 54cm TT is the same as one with a 74.5 STA and a 52.3cm TT. The average person wouldn't think that these frames would fit the same, but they do.
 

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C-40 said:
That's why your comparison is flawed. Trek and Fuji are two brands that use an odd-ball measuring system. Most other either use c-c or c-t. Their "56cm" frames are actually much smaller, either 54cm c-t or around 52.5cm c-c. When talking frame size, you have to specify the measuring standard.

Another common mistake is ignoring the seat tube angle. A frame with a 72.5 STA with a 54cm TT is the same as one with a 74.5 STA and a 52.3cm TT. The average person wouldn't think that these frames would fit the same, but they do.
I think we are agreeing, even in the comparison. If you think Fuji's sizing is messed up, Motobecane is even worse. (I've owned both) A 54cm claims to be measured center to top, but the actual measurement is Center to the top of the SEAT TUBE! I was a little miffed when I finally broke out the tape measurer. But then I bought the bike for parts, so it didn't really matter. The bike would actually fit quite well if the head tube was taller. I had to put a 350mm seatpost on it though. It's my "compact" bike with a non-sloping top tube.
Excellent point about the STA effecting reach. The calculation is obviously very natural for you and you just know the answer (engineer right?) but for the rest of us, is there a chart that one could glance at, or a simple rule of thumb (I'm no math wizard as you might tell) to use in gauging reach?
Thanks
 

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measuring method...

Well, the Motobecane method is the same as Trek and Fuji. They all call the seat tube length, the "frame size".

The rule of thumb on STA is to subtract 1cm per degree from the TT length of the frame with the numericaly smaller STA. The exact amount is the cosine of the STA times the c-c frame size. This is only completely accurate when comparing frames of the same size. That's the problem when comparing different brands. You have to figure out which sizes are close to the same.
 
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