Daniel Frost

Hi all,

Im new to triahtlon (8 months) I have got my head around most things but I cant figure this out.

Currently I am running a 16 speed setup with 39/53 front and my rear is an 8 speed with a 13/26. I have been given a better rim with a campag 9 speed 11/21.

Which is the better rear to use? ( i realise if its the nine I will have to upgrade my shifter, thats not a problem) Is there any pros and cons either way? The biggest events I will do is olympic distance if that is at all a consideration.

sirious94

eh 11/21 is kind of iffy, if you said 11/25 then definitely, if you said 11/23 then probably, 11/21 is more of your choice based on where you live and which tri's you will be doing. if you are doing Escape from Alcatraz and live near San Francisco, then no not at all. if you live in somewhere that is flat and has a few rolling hills, and you want to do tri's in the same area then yes an 11/21 would be very appropriate.

Pros:11/21 gives you a higher top speed (slightly),
Cons: 11/21 means you can't go up hills very easily (by hills i mean somewhere around 6% grade.)

Dalai

Ignoring compatability issues in case you are currently running Shimano...

What are the cogs sizing on the current wheel do you ride at race pace and on similar terrain to what you race? If you are constantly on or above 21 then stick with what you have.

The 11-21 will have a closer ratio so means you can optimise your cadence as the jump between cogs is less.

Daniel Frost

What are the cogs sizing on the current wheel do you ride at race pace and on similar terrain to what you race?

13/26

What is a good all round cluster to get?
I cant afford multiple rims/clusters at this stage. My racing and training is on all sorts of terrain

StanSeven

a 13/26 is good for climbing. The 13 is probably too low a gear for pushing speed on the downhills though.

11/21 is suited for flat land without steep hills. IMO, most people don't need an 11 gear. Take a look at a gear calculator and see what speed it takes to spin a 11X53 combo at 100 rpm.

For what it's worth, I'm fairly good at climbing and am relatively light at 6'0" and 165 lbs. I ride on moderate hills and find a 12/23 good.

Dalai

What I'm trying to ask is do you ever use the rear cogs with more than 21 teeth currently? If so stick with the current wheel.

Really depends on how strong a rider you are as to what cassette to use. On my TT bike, I have a straight block 11-21 and usually still keep in the big chain ring on the front on hills up to 5%. My road bike is 11-23 and i find with the small chainring it is fine for climbs over 10%.

If you are not a strong cyclist yet or good at climbing, a bigger range will give you more options to be able to find a gear...

Daniel Frost

I get what your asking now, yes I use higher than 21, so will stick with current wheel.