Changing front cogs

[Ade1865]

I have a supersix with sram apex gears. It came with a compact 50/34 on the front and 12/32 on the back.
The chain is getting to the point where it needs changing. I'm thinking of moving up to something like 53/39 on the front, as I find I'm mostly in the smaller rear gears a lot of the time. However, I like the flexibility I get from the 12/32.

Is there any reason why I would not be able to fit the 53/39 on the front with the 12/32 on the rear with the apex shifters?

Also, if i'm changing the chain, is it necessary/advisable to change the rear cassette as well? I've done about 5k miles on it over the year I've had it,and I dont really want to have to lay out for a new chain and cassette every year if i don't have to. Is there a way to tell if the cassette definately needs changing?

Cheers

 

[HLaB]

Yes there is a reason, the crank wont fit. I run 38/52 chainrings on a compact chain 110mm crank ordinarily thats the largest you'll get to fit, although I believe bbb have launched a 53t compact chain ring. You'll need a 130mm crank if you want to go larger. Edit sharky links below to other options.

 

[HLaB]

And with the chain its advisable to get a new cassette too but you might not want to fit it straight away but have it ready to fit if the chain slips on the old cassette,you may be lucky however and not need too, depending on the quality of the cassette and you'll can keep the new one to the next time. There's too many variables but I get somewhere in the region of 5k out of a chain and 10-15k out of a cassette. Edit lol I thinking K, km.

 

[uclown2002]

5K is pretty good! Have done maybe 3.6K on my current chain but should get 4K out of it.

 

[Sharky]

Yes there is a reason, the crank wont fit. I run 38/52 chainrings on a compact chain 110mm crank ordinarily thats the largest you'll get to fit, although I believe bbb have launched a 53t compact chain ring. You'll need a 130mm crank if you want to go larger.

I put some ta rings on a SRAM crankset. They were zephyr 54/40 and you can get them bigger
http://www.sjscycles.co.uk/ta-zephyr-110mm-bcd-5-arm-outer-chainring-silver-prod214/
But in the end went back to the original compact ones. The chain used to jump off the big ring and fall between the two rings.

Cheers keith

 

[cyberknight]

What about changing the cassette to an 11-32 ?
My boardman came with that as standard and unless your really grinding your gears or super fit you should not really need more on a day to day basis as the recommended leg speed, cadence or revs per minute of about 90 rpm on a 50x11 is 32 mph
a 53 front with a 12 back at the same rpm is 31.1 mph
So it would be cheaper and less hassle to fit the cassette and still gives you the wide range, i personally run an 11-28 with a standard compact and TBH i could do with a closer ratio cassette as i very rarely use the small chainring.

 

[Smurfy]

Stronglight 110BCD go up to 52T in Dural (cheaper, softer alloy), and 53T in Zicral (more expensive, harder wearing alloy).

 

[sreten]

Hi,

Going 11 to 28 at the rear makes more sense than bigger front rings.

You should get at least 2 chains life out of a cassette. Rotating 3
chains is an idea, to 1/16" stretch. Then new chains and cassette.
Keep the old chains and cassettes. Stretch is over 12".

On the third set you run them all to 1/8".
Then reuse the old cassettes and chains to 1/8".

Its generally reckoned 1/16" is fine for cassettes and 1/8" for the front rings.
I.e. a chain stretched to 1/8" has toasted the cassette and stretched
to 1/4" has toasted the front rings, in terms of running a new chain,
even if it doesn't jump, the chain will wear out much faster.

However if you never fit a new chain, you can take it a lot further,
by carrying on rotating the chains and the cassettes as they wear.
With rotating 9 chains and 3 cassettes you can cover a
phenomenal mileage on the front rings as they wear.
How phenomenal depends on maintenance.

The point is to never have a chain much more stretched
than the cassette or front ring teeth wear. If you do the
chain will rapidly deteriorate and rapidly wear the
gears (much more so than normal) in the process.

rgds, sreten.

 

[Ade1865]

Thanks for the replies people, gives me plenty to think about