Which cassette

[jbrow1]

Building up an older bike for cx. Last year I ran a 36/46 chainring set, and a 7 speed 14/28 freewheel.
This year I think I will just put a compact crankset on so it will be a bit better for road riding, then just use the 34 while doing singletrack, or dirt/grass type stuff.

My question is what 8 speed cassette do you think I should go with? I really don't need anything with an 11 on it, a 12 is still pushing it unless in a paceline on the road. But with a cassette I can get a 30 or 32 big cog and not sure which I would like best. Last year there were only a handful of times I would've liked a lower gear than my 36/28. Some was on mnt bike singletrack, and the real killer was a long gradual rise with tall grass on the last race coarse I was at.

Anyhow, just looking for some input.

[flargle]

Are you sure your derailleur would have the capacity for 34/50 in front and 12-32 in back?

I think you would be unhappy racing with 34/50 in front, I'd use a 42t big ring. Or just 36t single ring, something like that.

I think 12-30 is pretty good for rear.

[ThermionicScott]

With an 11 or 12 at the top of your cassette, that 46T chainring would be plenty tall. Speaking just for myself, I hate the big gap in 50/34 compacts, and I think I'd hate it even more in critical situations.

[jbrow1]

The big ring would be for road use only, and the 34 (or 36) for dirt use only and a downtube shifter for the front. I suppose it would be easy enough to find a decent 36/46 just as it would a compact.

Not sure if my RD would work or not, need to look into things more. Guess I should look up a gear chart and see what I had last year, and what I think I want this year compared to the stuff I already have sitting in boxes.

Yes, the 46 was good last year even with the 14 for any of the racing I did, which only one coarse had a spot that was long enough to warrant shifting anyhow. So time to go back to thinking I guess. Putting together a bike right now for the wife, and using my last years cx crankset on it.. so might have to tear it apart come fall or find a new one. That's really why I was curious about just using a compact.