large and small chain ring differential?

shakey88

Hi,i currently have a compact 50/34 set up on my road bike.Is it possible to change the big chain ring to a 52t and run a 52/34 set up,or would i have to change the small chain ring too.Maybe a 52/36?
Cheers

sungod

depends on the capacity of your front mech - this is the difference in number of teeth between big and small rings

50/34 - caoacity is 16t
52/34 - capacity is 18t

15t or 16t is typical capacity for a front mech

going over the rated capacity might result in the chain dragging on the cage or jamming

what cassette are you running? unless you are consistently spinning out on the 50 and smallest sprocket then the 50 should be ok

shakey88

Thanks for replying.I'm running a 23/11 cassette but i feel i need a bigger gear for sprinting at the end of a race.So you think a 52/36 would work?

sungod

52/36 will be the same capacity as your existing rings, you'll just need to move the front mech up a smidge

on 50/11 at cadence 100 you'll be doing around 58km/hr 36mph, with 52/11 it'll be around 60km/hr, 37mph, *if* you can generate the extra power to maintain the same cadence

http://www.analyticcycling.com/QCHome_Page.html

dennisn

shakey88 wrote:

Thanks for replying.I'm running a 23/11 cassette but i feel i need a bigger gear for sprinting at the end of a race.So you think a 52/36 would work?

A bigger gear than a 50-11???? :roll: :roll: :roll:

shakey88

yep,not trying to brag here or anything like that.Just feel i'm over the top of the gear when i'm sprinting in 50/11. Need more "bang for my buck" as they say!

redddraggon

shakey88 wrote:

Thanks for replying.I'm running a 23/11 cassette but i feel i need a bigger gear for sprinting at the end of a race.So you think a 52/36 would work?

Cav only normally sprints in 53-13 or 53-14, so your 50-11 should do you fine.

markos1963

You're strong enough to spin out on a 50/11 but not strong enough to race without a 34/36? :roll:

shakey88

well i'd rather not change the 34t but it seems i will have to as it won't work with a 52t big ring.i need the small ring when i'm not racing

shakey88

redddraggon wrote:

shakey88 wrote:

Thanks for replying.I'm running a 23/11 cassette but i feel i need a bigger gear for sprinting at the end of a race.So you think a 52/36 would work?

Cav only normally sprints in 53-13 or 53-14, so your 50-11 should do you fine.

:roll: surely Cav sprints in 53/11?

Pseudonym

shakey88 wrote:

yep,not trying to brag here or anything like that.Just feel i'm over the top of the gear when i'm sprinting in 50/11. Need more "bang for my buck" as they say!

If you're over the top of 50/11, then i guess you must be winning all your sprints - which begs the question why do you need a bigger gear? What category level do you race at, as a matter of interest..?

markos1963

shakey88 wrote:

well i'd rather not change the 34t but it seems i will have to as it won't work with a 52t big ring.i need the small ring when i'm not racing

Well the quickest and easiest but not the cheapest is to get another chainset. Although there are loads of people selling standard doubles(53/39) on Ebay so you can get a bargain for the price of a couple of chainrings. This way you can just whip out the compact after training and put the standard on for the race.