Hi, all:

We're getting ready to replace the cassette on our DaVinci global venture.

Our existing one is a SRAM PG980 11t.

Amazon and other online cycling stores offer two sizes.

What is the difference between an 11-34 and an 11-32?

What do these numbers refer to?

Thanks for your help!

Count the teeth on the largest cog of your current cassette. If it has 32 teeth and you sometimes find yourselves wanting a lower gear, go ahead and buy an11-34. If your happy with your current gearing, then buy the same cassette, 11-32 or 11-34. If you never use the largest cog, whether 34t or 32t you might consider a cassette with closer spacing. We use and 11-32 and there are times I'd like the 34t cog it things get really steep, but the spacing on the 11-32 works better for us. I think it's all about the type of riding you do and how strong a team you are. If you are replacing your cassette you should put on a new chain as well unless your chain is very low mileage.

Thanks, rdtompki, I thought you might reply!
And thanks for the 11-32/11-34 explanation.

Just be aware that you may (or may not, it depends) need to increase the length of your chain if you increase the size of your largest cog.

these are the spockets you get at least for shimano m760 9-speed (SRAM is probably similar). For a long time we rode the 32, but now prefer the 34 - often you can stay out of granny, but you do lose some medium gears