Noob Gearing Question

[Sneaky]

Hi all,

I have just purchased a racing bike with the aim of doing some circuit racing.

The 2 front rings have 53 and 39 teeth and the cassette is 11-23.

My question is when I am in the 53 ring, because of chain lines etc, can all the rings on the cassette be used or half of them or more than half. The same with the 39 ring is it possible to use all of the back cassette or is it better not to.

Thanks

 

[spandex]

It will be fine they do say dont do (big and big, small and small) but if your bike is set up right it will be fine. You can find out by putting the chain in small and small then if your mech is bent over so the chain is coming back onto the mech your chain is to long by one or two links.


p.s. welcome

 

[Sneaky]

cheers spandex,

So what you are saying is that as long as you don't go to the extremities cross ways, you can use the rest.

Is that the most efficient way or is it better to find matching gears and change the front ring instead.

Thanks for getting back so quick

 

[Aperitif]

Hello sneaky!

http://sheldonbrown.com/gears/

What spandex says - usually big front and smallest to middle, smaller front, middle to big rear. Sheldon Brown's gear calculator tells you what is the best 'crossover' point for changing etc. The number of revolutions of pedals per minute is also a factor with some people's riding - it's called cadence.
Have fun cycling and don't forget to call in at the café where there are plenty of opportunities to drink tea with the nobs.

 

[spandex]

If you wish to keep your bike the way it is just make swore the chain is not to long. Most local bike shops (LBS) will tell you not to go into big big, small small as a lot of bikes arnt set up right. It will wear your chain and rings quicker but if your aim is of doing some circuit racing you will need lots at the start. But keep an eye on which rings you are using and get it adapted for that.

 

[Sneaky]

Cheers fellas.

 

[spandex]

Keep on coming back Sneaky we like newbes

 

[bonj2]

assuming it's 9sp your 11-23 is 11-12-13-14-15-17-19-21-23,
so with your big ring you're getting
(small sprocket, good) --- > (big sprocket, bad)
4.82-4.42-4.10-3.79-3.53-3.12-2.79-2.52-2.30
with your small ring you're getting
(small sprocket, bad) --- > (big sprocket, good)
3.55-3.25-3.00-2.79-2.60-2.29-2.05-1.86-1.70.

so going up the gears on your smallest chainring, once you get to sprocket 6, it's duplicated by big ring with third sprocket, but small ring with 6th is better than big ring with 3rd, as the former's 3 away from crossover while the latter's only two away from crossover. So if you use 1-6 on your small ring and 4 - 9 on your big ring you should be able to achieve all possible ratios (or close to) without unnecessary crossover.

 

[Steve Austin]

assuming it's 9sp your 11-23 is 11-12-13-14-15-17-19-21-23,
so with your big ring you're getting
(small sprocket, good) --- > (big sprocket, bad)
4.82-4.42-4.10-3.79-3.53-3.12-2.79-2.52-2.30
with your small ring you're getting
(small sprocket, bad) --- > (big sprocket, good)
3.55-3.25-3.00-2.79-2.60-2.29-2.05-1.86-1.70.

so going up the gears on your smallest chainring, once you get to sprocket 6, it's duplicated by big ring with third sprocket, but small ring with 6th is better than big ring with 3rd, as the former's 3 away from crossover while the latter's only two away from crossover. So if you use 1-6 on your small ring and 4 - 9 on your big ring you should be able to achieve all possible ratios (or close to) without unnecessary crossover.

tell the truth Bonj. You don't understand what you've written there do you?

 

[Aperitif]

Ssshhh Steve - he's sleeping... I think Abitrary started roughing him up somewhere or the other...he seems to have been on the rampage everywhere