New bike gear comparison?

[PugwasHDJ80]

Hi Guys,

Buying a new bike as my old is too small (I bought the wrong sized frame)

My old bike is a 3x9 26er

the new one "might" be a 1 x 11 29er

For me the gearing on the 26er is wrong- first is too low and 27th too high.

so what i'm trying to work out is what are the gear ratios i'm using on my 26er and how do I choose the drivetrain components on the 29er? lots of spreadsheets available, but none that I seem to be able to work out how to use!

[MiseryStreak]

PugwasHDJ80 said:

Hi Guys,

Buying a new bike as my old is too small (I bought the wrong sized frame)

My old bike is a 3x9 26er

the new one "might" be a 1 x 11 29er

For me the gearing on the 26er is wrong- first is too low and 27th too high.

so what i'm trying to work out is what are the gear ratios i'm using on my 26er and how do I choose the drivetrain components on the 29er? lots of spreadsheets available, but none that I seem to be able to work out how to use!

This is what you need, works like a dream:

http://sheldonbrown.com/gears/

The SRAM XX1 system uses a cassette with something like 10-12-14-16-18-21-24-28-32-36-42. You can change the chainrings around depending on the ride you're planning (if you can be arsed), but if you choose a middle sized 34 tooth chainring, it will give you a maximum gain ratio of 7.0 and a minimum of 1.7.

Compared to a typical 3 x 9 drivetrain with 22/32/44 crankset and 12-34 cassette, on a 26er, giving a maximum gain ratio of 7.1 and a minimum of 1.3.

So you will lose out a bit, especially at the low end, and you will have less options in between, but overall you will probably have all the gears you need, and you lose the weight of 2 chainrings, front derailleur, one shifter and the cable.

[matt-ITR]

32t on the 1x11 will be best for most places with a 29er.

30t if you live somewhere very hilly, or struggle on the hills.
34t if you don't have problems with steep hills.