cassette , changing the gear combinations on an ultegra

[reacher]

hi
can i change the gear combinations on a ultegra 10 speed cassette ,
ie , buy a 12 x 25 and a 11 x 28 cassette
remove the 13 from the 12 x 25 and put the 28 on ?
to make effectively a 12 x 28 cassette so that i jump from a 25 to a 28
thanks

 

[redcard]

Not with an official Shimano cassette, as they consist of 7 single rings with the top 3 rings combined into a single unit.

Not sure about unofficial cassettes, but would imagine they're probably identical

 

[Cycleops]

No you can't, but why would you want to?

 

[jdtate101]

On the 11-28 the last but one cog is a 24, so small difference, but you cannot do what you ask because of what redcard said.

 

[MattHB]

hi
can i change the gear combinations on a ultegra 10 speed cassette ,
ie , buy a 12 x 25 and a 11 x 28 cassette
remove the 13 from the 12 x 25 and put the 28 on ?
to make effectively a 12 x 28 cassette so that i jump from a 25 to a 28
thanks

Why not just buy a 12-28?

 

[lulubel]

Why not just buy a 12-28?

Or use the 11-28?

 

[reacher]

i wanted the jump from a 25 instead of a 24 to 28 , as to why , complicated , i was being fussy , i want the 23 and 25 to climb on of which the 25 is my get out of trouble gear and i wanted the 28 as a get out of serious trouble gear , if i have the 11 x 28 i only get a 24 , i'm not sure its small enough for what i wanted , the 23 and the 25 i know is usefull gears for me , i'm doing the alp d'huez later this year so i'm trying to get the combinations right , what i may do then is take a 11 x 28 cassette , with me , its this start ramp of nearly 2 k that i'm thinking of , i dont want to go burning all my matches going up it ,

 

[Peteaud]

Building Custom Cassettes


Sheldon Brown

http://sheldonbrown.com/k7.html

Scroll down to the above title.

 

[lulubel]

I think you're overthinking it, to be honest. I do climbs of over an hour on a regular basis, and if one gear's a bit higher than I want on a particular section and one gear's a bit lower, I just use the lower one and go a bit slower.

I don't think you can ever have the perfect range of gears for all eventualities. What happens if a particular stretch is half a degree steeper or shallower than you expect, and it falls between gears?

 

[jdtate101]

You should have no difficulty doing most of the upper Alpe on a 34x24 and save the 28 for the first 2km. The upper part is mostly 7-8% avg, yes it's hard work, but not that hard. Just pace yourself, listen to your body and keep that cadence high.

 

[reacher]

i think your right actually , its just one of those , can i do it things that i wondered about , its that a mate of mine said that i would need a 28 to go up the alp d'huez when i was pretty certain that a 25 would be enough , i tend to like close ratios and i was trying to get around the jump from 24 to 28 and still keep my 25
i'm useing a 39 x 53 chainset

 

[twentysix by twentyfive]

I think you're overthinking it, to be honest. I do climbs of over an hour on a regular basis, and if one gear's a bit higher than I want on a particular section and one gear's a bit lower, I just use the lower one and go a bit slower.

I don't think you can ever have the perfect range of gears for all eventualities. What happens if a particular stretch is half a degree steeper or shallower than you expect, and it falls between gears?

Triple chainring (the granny ring) sorts that - especially on a close ratio cassette.

 

[lulubel]

Triple chainring (the granny ring) sorts that - especially on a close ratio cassette.

But with a close ratio cassette, you might not have enough gears at one end or the other, which is why reacher wants a wider range cassette in the first place.

 

[reacher]

i'm probably being to fussy to be fair, i'm almost certain that a 39 x 25 will be in my comfort zone for the first part , just dont want to get all the way out their and find i need a smaller gear ,

 

[TheDoctor]

Fit the widest range cassette you can IMHO. I always want a lower gear...