[biker45]

Can someone please explain to me what is a compact drive and what are the advantages/disadvantages.

Thank you,

Craig

 

[danl1]

Can someone please explain to me what is a compact drive and what are the advantages/disadvantages.

Thank you,

Craig

What is: a crankset with a 110mm bolt circle instead of 130mm. This permits the use of (normally) 34/50 instead of 39/52 chainrings.

Advantages: Gets closer to the lower gearing of a triple without the weight or most of the shifting penalties. Continues the use of a conventionally-sized rear der. Lighter weight than a trip, marginally less than a standard double.

Disses: Can make for some funky shifts, as it's one tap in front to three or four in the rear, as compared to two or three on a conventional setup. Can put the crossover in an inconvenient spot for some riders' power curves. Some stronger riders have trouble losing the high end, but spinning out at 34mph isn't a realistic problem for a lot of other riders. Depending on the drivetrain, a wide-range cassette may give some of the advantages for less money.

I ride a compact setup, and love it. There are a lot of people who've never them that don't. It's not earth-shattering either way. I've had conventional setups, and I've had triples, and the compact hits a sweet spot for me. All I can say is opinions vary.