Sizing Q

[Mike V]

Hi guys,

I am 6'1 and read on one website that I should be looking at frames in the 60-62cm range. (Usually XL frames)

I heard some conflicting advice though that says I will be fine down to a 57cm frame. How does that sound? Can the appropriate adjustments be made on a 57cm frame?

Thanks in advance.

 

[Bigtwin]

No sure way to know. You need to look at the geo of the frames. Some makes change little on the sizes, some more. So some have large "overlap" between sizes, i.e. with stem and saddle adjustments you can be in the same fit spot on both sizes.

Also depends on your shape - arm v leg length, and how tall you ride.

Roughtly, I'd say 57 is about the min - I am 6' and have a 57 that fits fine. I used to have a 56 TT frame that was fine. But I also have a 60 that does too. And I have 2 Cannondale MTBs - a M and an XL, both fit fine for slightly different set-ups.

 

[John the Monkey]

Different frames are measured in different ways too.

(Compact frames especially).

Go to a local bike shop that you trust, that will let you try the bikes.

I'm 6'2" and ride an "L" giant SCR2.0, for what that's worth. According to Giant, I'm between L and XL - my LBS advised that the smaller frame would be better, and let me try it to see whether they were right or not.

 

[jimboalee]

There are several methods of determining frame size.

The two that I trust are 1/ Veloweb, by Randochap, and 2/ SHR. ( Seated Height Ratio ).

Veloweb's method relies on the subject to have a good idea of what the pressure of a saddle feels like, while SHR negates this requirement.

Mass produced bike manufactures have reams of information from various universities and medical studies worldwide, and have dimensioned their frames based upon an 'Adult male norm', or average man.
If you're after an Off The Peg bike, you don't need to worry about the size within 2cm. If you are midway between sizes, go for the smaller. It will be lighter and stiffer.

I have a spreadsheet from old methodologies gained from a reputable Framebuilder in Birmingham, and a draughting package on my PC to draw up a frame. I must be pretty normal because my SWorks is within millimeters of perfection.

Specialized are pretty good at publishing the frame dimensions. My SWorks is 2mm adrift in Reach and 4 mm adrift in Seat tube length ( small ). This said, it’s the most comfortable and easiest bike to ride that I've ever owned although it is so far out.

Once you've done both measurement methods and got results within ¼", you can take the frame size as 2/3 of the result.

Some folks say frame size is 1/3 of your height, but this is dodgy due to SHR variation. I have even seen frame size as being leg length minus 9". Ignore these.