Cyclocross - Roadie asks..What size cross to get

Hey folks
I ride 58 CC top tube road bike stand over 32.5 issish.

What size Cyclocross would I get? I was told one size smaller so a 56, is that correct?

Or, How are they calculated?

Thanks
Rob

The tip comes from some CX bikes having tall bottom brackets, but that's an old trend and not universal these days.

You're better off going with a frame that has an effective top tube length the same as your road bike and backing off 1cm in stem length. You may also want to set the saddle to bar drop to be 1cm or so less than on your road bike (more comfort, better control).

This is a topic to Google and learn more about. Consider this the very abridged answer.

Also depends if you plan to agressively ride it. I prefer to be stretched out on my road bike, and ride a 55cm Lemond, which is pretty equivalent to 56 in most other brands. In my Cross bike (Fuji Cross Pro) I went to 54cm with it. The bike just felt "right" when riding it and I've had no fit related issues in well over 1k miles. When you test ride, you need to at least get in some grass or loose gravel to get a feel, it's certainly not the same handling as a road bike in that respect. You need it to be pretty quick and nimble without being twitchy. Top tube clearance you'll also want a bit more than most road bikes need.

I soooo wanted a Specialized Tricross, but 54 was too small, and due to the arch in the top tube on them, 56 didn't have enough standover.

Size the frame just the same as a road bike. Standover is irrelevant. In fact standover will be slightly tighter because of the larger tires, doesn't matter.