Bike sizing. for the noob.

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Permalink Reply by Hamilton on February 4, 2010 at 9:13am

Many bike shops offer bike fitting, that's your best bet. If you can't do that then take some for a test spin. My wife is 5' 7" and usually rides a 52 or small for most brands, start there.

I don't think you need extra clearance for 'cross so I ride the same size bike in 'cross and road. I just set up the stem/spacers for a little more upright position on my 'cross bike.

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Permalink Reply by m750 on February 4, 2010 at 6:11pm

The real problem none of the local shops carry any cross bikes, so unfortunately I can't really test them out for size. Having to shop on the web is making this a bit harder. I've basically been having to ask people what they ride, and how tall they are.
AO

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Permalink Reply by cxchiva on February 5, 2010 at 4:35am

I have read more often than not that your cx bike size doesn't have to be different than your road set-up and making sure you have about the same top tube length. I ride the same size frame for road and cx only my stem is 10mm shorter on my cx bike and my saddle is slightly more forward. Dont' trip on it too much, get somethnig in the ballpark and then make adjustments from there. My problem with a shop or bike fit is that going that route doesn't replicate the position/hammering/ or puke factor you will experience in a race. So riding the bike passively around a parking lot may not do you justice. I personally like to go through different stems, handlebars, saddles and adjustments and figure it out myself. Going by what people ride because of how tall they are may not be a good measure. For example I am 6"3" and I can ride a 58-59cm because my inseam is short, whereas I know guys that are just as tall that ride a 61cm.

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Permalink Reply by m750 on February 5, 2010 at 6:35am

Perhaps I'm not explaining this well enough. The one bike I was able to find to test out was a ridley, it was sized 52. Thinking I've got a 54 road bike and it is a tad big, this should be about the right size. WRONG! it's clearly way to big for me, I could barely ride it, let alone at any pace.
I was just wonder if there were any general sizing rules of thumb, IE Ridley is sized super big, -1 size, etc.
I guess I'll just need to play it by ear, and hope I can find something that'll fit.
Thanks,
AO

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Permalink Reply by Hamilton on February 5, 2010 at 8:31am

Sizes as listed can vary quite a bit from one manufacturer to another. You can readily view the actual dimensions and geometry of specific bikes by going to the website of the manufacturer. Obviously there are more things to consider but mainly you want to look at the length of the top tube and stand over clearance.

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Permalink Reply by Jonathan Berube on February 8, 2010 at 5:45pm

i am also in the process of buying my first cross bike. i have several track bikes, and my sizing with those is very different from road bikes. this is due in part to the fact that the bottom bracket is higher for increased pedal clearance, resulting in a shorter seat tube. is this true for cross bikes as well?

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