Racing gear ratios

bukowski102

Hi there
I will be racing for the first time this year and have bought my new wheels, I am deciding which cassette to buy e.g 11-23, 12-27. Im honestly not sure how the configuration works with regards to gear ratios, I am racing mostly on flat courses and dont need granny gears for climbing, more of a spinner but can push a fairly large gear over the flats.
any suggestions will be greatly appreciated
thanku hap new yr

rokkala

You don't say whether you have a compact or double up front? Although if all your racing is going to be on pretty flat courses then theres no real reason to get the 12-27.

With the 11-23 the spacing between the gears will be a lot closer, meaning it's easier to find the ideal gear for yourself.

bukowski102

Rokkala wrote:

You don't say whether you have a compact or double up front? Although if all your racing is going to be on pretty flat courses then theres no real reason to get the 12-27.

With the 11-23 the spacing between the gears will be a lot closer, meaning it's easier to find the ideal gear for yourself.

sorry yeah its a compact, thanks, so 11-23 is the standard gearing?

mrdsgs

Assuming non-compact cranks and 10 speed and 53 or 52 and 39 or 42 up front I would go for 12-23 which only only misses 20 and 22 so will make for smooth chnages on either ring. You will not need an 11 on the flat with a 52 or 53 big ring. Fora hillier course you may well need 12-27 or at least 12-25.

If using a compact with perhaps 50/34 I would go for 11-23

jonmack

I'm gonna be running standard (52/39) with 11-25.

sheffsimon

For all the circuits I race on I use 53/39 and 12/21 10 speed straight thru cassette. I did have a 12-23 but sometimes found I wanted the gear I was missing.

Most of the circuits round here are rolling or steady climbs rather than with steep climbs, so always in big ring - if you arent, you are out the back.

Also found those ratios OK for Peak District, where I do all my training miles.

In summary, if you arent racing up steep climbs get a straight thru cassette.

Pross

As the OP is using a compact I would say 11 - 23 unless doing seriously hilly races. Going up hills on virtually all the courses I've raced on (mainly in hilly South Wales) in 34 x 27 would leave you having to pedal very fast! Even in the "good old days" of 42 x 21 lowest gears it was unusual to have to use my bottom gear. Besides, you wouldn't want to spin out in a 42 mph sprint like someone on the beginners forum claims to have done!!

I'm unfit and heavy and even on training rides I can get by on 39 x 25 so you should be fine.

John.T

With a compact I would go for 11/21. The 11/23 looses the 18 which gives a very useful 75" gear. This is duplicated (nearly) on 34/12 which is not a very good place to get to under pressure. If you need anything lower than 34/21 you are probably out the back anyway. If your races are in hilly country I would go for 12/23. 100rpm on this is over 32 mph. Just sit on a wheel down hill above this and get pulled along. I have done 47mph in a hilly TT using 50/12 very easily.

Rodrego Hernandez

John.T wrote:

With a compact I would go for 11/21. The 11/23 looses the 18 which gives a very useful 75" gear. This is duplicated (nearly) on 34/12 which is not a very good place to get to under pressure. If you need anything lower than 34/21 you are probably out the back anyway. If your races are in hilly country I would go for 12/23. 100rpm on this is over 32 mph. Just sit on a wheel down hill above this and get pulled along. I have done 47mph in a hilly TT using 50/12 very easily.

Totally agree with this

jgsi

Rodrego Hernandez wrote:

John.T wrote:

With a compact I would go for 11/21. The 11/23 looses the 18 which gives a very useful 75" gear. This is duplicated (nearly) on 34/12 which is not a very good place to get to under pressure. If you need anything lower than 34/21 you are probably out the back anyway. If your races are in hilly country I would go for 12/23. 100rpm on this is over 32 mph. Just sit on a wheel down hill above this and get pulled along. I have done 47mph in a hilly TT using 50/12 very easily.

Totally agree with this

also agreed last thing you want to be doing in a race is frontshifting but the financial burden of it.. running 10spd means DuraAce for a 11-21.. no Ultegra or 105 option available as far as I can research... unless someone has an alternative

mostly harmless

JGSI wrote:

unless someone has an alternative

BBB do an 11 - 21 for £45ish but, based on experience of their other cassettes, it'll sound like a washing machine full of spanners when compared to Shimano.

maryka

Spend some quid on a cassette lockring remover and chain whip, then get whatever cassette you currently don't have (if you're on a 12-27 on your regular wheels, get a 11-23 or vice versa) so you have options depending on what races you do. Swapping them between wheels take less than 5 min. A few different sized cassettes are never a bad thing to have at your disposal and they will last a lot of miles if you take care of your chain.

sheffsimon

mostly harmless wrote:

JGSI wrote:

unless someone has an alternative

BBB do an 11 - 21 for £45ish but, based on experience of their other cassettes, it'll sound like a washing machine full of spanners when compared to Shimano.

I have Miche Campag 12-21 10 speed - not had a problem with it, but then again its on Campag wheels with a clicky freewheel. Sweet shifting though. Not sure if Miche do a Shimano 12-21

jonmack

Miche:
http://www.miche.it/en/catalogo/catalog ... mato-10-sh
Buy: http://www.tredz.co.uk/.Miche-Primato-1 ... _32284.htm

BBB:
http://www.bbbparts.com/proinfo3.php?N= ... =EN&Y=2011
Buy: http://www.pro-bike.co.uk/gears/21947-b ... imano.html

John.T

I have a BBB 11/21 for some TTs. It works fine but does not change as smoothly as my 12/23 Ultegra. Perfectly usable. It feels just like Campag.





Should I have said that? :twisted:

jonmack

Fine by me, I ride SRAM :P