What cassette range does ultegra rear derailleur accomodate

fat bloke

Did some boards searching and googling and looking for a more definitive answer.

If I was Alpine Col hunting, what are my cassette options without having to change derailleurs etc. Current setup is 11 speed ultegra (52:36) and what's more than likely an 11:25 at the back (I'd have to check).

Biggest dinnerplate seems to be an 11:32. - So can I just pop that on and spin away whistling nonchalantly or do I need to look at changing chains and derailleurs and all that stuff?

1bryan

fat bloke wrote: »

Did some boards searching and googling and looking for a more definitive answer.

If I was Alpine Col hunting, what are my cassette options without having to change derailleurs etc. Current setup is 11 speed ultegra (52:36) and what's more than likely an 11:25 at the back (I'd have to check).

Biggest dinnerplate seems to be an 11:32. - So can I just pop that on and spin away whistling nonchalantly or do I need to look at changing chains and derailleurs and all that stuff?

to an 11/32 I'd say no. I tried going from an 11/25 (53/39 on the front) to an 11/28 last year and I couldn't get the chain on the 28. My research told me that it should have worked, but it would be marginal. So I'd say going to a 32 wouldn't be doable.

magicbastarder

you probably have a short cage rear mech, which seem to max out at about 28 teeth on the cassette. unless i'm misunderstanding the situation.

Weepsie

Depends on if you have the short or medium cage. You can get a 32 on with the Medium cage

http://bike.shimano.com/content/sac-bike/en/home/components11/road/ultegra1/rd-6800-gs.html

fat bloke

Right. I thought it might be a cheaper option than going for a compact chain ring. But it seems from gear calculators anyway that there's at least as much reduction (if not more) in gearing from cassette changes than front chainring.

But if the derailleur and then also the chain needs changing then the costs would be similar.

Though either would be cheaper than double knee surgeries

07Lapierre

For the alps i use a Compact (50:34) with a 27 sprocket. that gives a lowest gear of 1.25

To get the same with a 52:36, you'll need at least a 28 on the rear.

I don't consider myself a good climber and even I would think a 32 is too low. (you'll be spinning at 90rpm and barely moving)

To fit a 32 sprocket, you'll need a long cage rear derailler and a longer chain.

fat bloke

Yeah a 32 is big alright but I wonder and the other sprockets are then, is it 32,30,28 maybe? I'd havr to look it up.
I've done some long alpine sportives and towards the end I was honking a 34:28 @60rpm and would have gladly selected a 30 or a 32 if I'd had the option

07Lapierre

The Alps are hard! I suspect if you had a 32, you'd still glady select a 33 if you had the option!

smacl

07Lapierre wrote: »

To fit a 32 sprocket, you'll need a long cage rear derailler and a longer chain.

Medium cage will do 50/34 with 11/32 on Ultegra, that's my current setup. Long cage is for triples and mountain bikes.

ford2600

5700/6700 short cage etc will handle 30 fine with a few provisos
*it's outside 27 max spec
*if you just want it for Alps it'll work fine but you won't be able to use full gear range; chain will either be to long for 36/11-12 or too short for 52/27-30.
*If you are disciplined (with it enough when bollixed) you won't mangle rd or wheel or whatever

I've my bike set up like that for 2 years or more without bother but if are a habitual cross chainer don't even try

dragratchet

im off to the Pyrenees in June. currently have a 52-36 with a 28 on the back, intending on getting a compact chain set for the trip but toying with the idea of a 32 also. im about 85kgs and a decent enough climber for my size. anyone know whether the Pyrenees would require a 32? could do without having to change my rear mech and chain.

07Lapierre

smacl wrote: »

Medium cage will do 50/34 with 11/32 on Ultegra, that's my current setup. Long cage is for triples and mountain bikes.

I stand corrected! thanks

fat bloke

Is there any easy way to identify whether my derailleur is short or medium?


Edit I see here they have the two pictured

http://www.wiggle.co.uk/shimano-ultegra-6800-rear-derailleur/

If I were to guess I'd say mine's the medium one, which means I could lob a 32 on if I wanted.

07Lapierre

Unless you've upgraded or swapped the derailler's...a bike with a 52:36 chainring with a 11:25 cassette will have a short RD.

fat bloke

07Lapierre wrote: »

Unless you've upgraded or swapped the derailler's...a bike with a 52:36 chainring with a 11:25 cassette will have a short RD.

Right ok. But just looking at the bike spec as new (I bought is second hand) here:
https://www.giant-bicycles.com/gb/tcr-advanced-pro-1-2016

It appears it came as standard with a 27. -I should have done this before starting the thread of course but I'd need to go home and count the teeth to see what the actual story is. :rolleyes:

1bryan

fat bloke wrote: »

Is there any easy way to identify whether my derailleur is short or medium?


Edit I see here they have the two pictured

http://www.wiggle.co.uk/shimano-ultegra-6800-rear-derailleur/

If I were to guess I'd say mine's the medium one, which means I could lob a 32 on if I wanted.

or, just measure the hanger

http://www.sheldonbrown.com/harris/derailers-rear.html

fat bloke

1bryan wrote: »

or, just measure the hanger

http://www.sheldonbrown.com/harris/derailers-rear.html

Cheers. So does "Centre to centre" refer to the two jockey wheels?

smacl

Just checked, my Ultegra medium cage is about 135mm long all in, see below

cdaly_

07Lapierre wrote: »

For the alps i use a Compact (50:34) with a 27 sprocket. that gives a lowest gear of 1.25

I don't consider myself a good climber and even I would think a 32 is too low. (you'll be spinning at 90rpm and barely moving)

Ha! Last March on the Priest's Leap, I was grinding a 26x32 at 40rpm before I fell over. That was 26 on the front, 32 on the rear.




There's no such thing as too low...

triggermortis

I've a 32 on the rear and my Ultegra cage is definitely a medium size

1bryan

which from center-of-jockey-wheel to center-of-jockey-wheel would correlate with the sheldon brown table.

smacl

1bryan wrote: »

which from center-of-jockey-wheel to center-of-jockey-wheel would correlate with the sheldon brown table.

Not sure, but you'd want to check that the Sheldon Brown stuff is up to date, as 32t cassettes on road bikes are a relatively new thing. Of course if you want a really wide range cassette there's always this

Wishbone Ash

07Lapierre wrote: »

The Alps are hard! I suspect if you had a 32, you'd still glady select a 33 if you had the option!

I normally take a 30 to the Alps but a few years ago, I had to change bikes at the last minute (mechanical) and take my Ridley with a 27. I was anxious about how I'd manage but it was fine. A lot of it is psychological!

cdaly_ wrote: »

Ha! Last March on the Priest's Leap, I was grinding a 26x32 at 40rpm before I fell over. That was 26 on the front, 32 on the rear.




There's no such thing as too low...

Yes, but Priest's Leap is brutally steep - unlike most of the alpine Cols which have an average gradient in the 6-8% bracket.

Unknown Soldier

fat bloke wrote: »

Did some boards searching and googling and looking for a more definitive answer.

If I was Alpine Col hunting, what are my cassette options without having to change derailleurs etc. Current setup is 11 speed ultegra (52:36) and what's more than likely an 11:25 at the back (I'd have to check).

Biggest dinnerplate seems to be an 11:32. - So can I just pop that on and spin away whistling nonchalantly or do I need to look at changing chains and derailleurs and all that stuff?

With 11s you need a GS(Medium) RD. There is an 11-32 Cassette available, but there is a new Dura Ace 11-30, and that might filter down to Ultegra. Might...

On a Shimano 10s system, depending on your RD hanger, you might get away with a 10s 12-30, even though Shimano recommend a max of 28. But as mentioned, there is no 11s xx-30

A lot of info here http://si.shimano.com/

http://si.shimano.com/pdfs/ev/EV-RD-6800-3608D.pdf

smacl wrote: »

Just checked, my Ultegra medium cage is about 135mm long all in, see below

Are you sure that's a GS? Mine looks a lot longer!

smacl

Unknown Soldier wrote: »

Are you sure that's a GS? Mine looks a lot longer!

11/32 cassette and was listed as GS when I bought it, but no markings on the derailleur itself other than Ultegra. I reckon the Sheldon link is possibly out of date though, centre to centre cage length of the Ultegra is 86mm which he has as SGS and both the Deore triple on my hybrid and Veloce triple on my road bike are 96mm centre to centre.

2 Wheels Good

dragratchet wrote: »

im off to the Pyrenees in June. currently have a 52-36 with a 28 on the back, intending on getting a compact chain set for the trip but toying with the idea of a 32 also. im about 85kgs and a decent enough climber for my size. anyone know whether the Pyrenees would require a 32? could do without having to change my rear mech and chain.

I was in the Pyrenees 2 1/2 years ago on a 50-34 with a 12-27. Got on fine.
The Hautacam has serious ramps but the rest were nice steady climbs. You'll always want a lower gear but most are manageable with a 27/28 on the back.
Hoping to go back to the Alps this year and will move to a 11-28 for the downhills.

Daroxtar

As already said, the vast majority of climbs in the Alps don't have sustained segments over 10% so 11-28 would be sufficient. The only thing I'll say is if you're doing a long day with climbing towards the end then the 11-32 is great. Sometimes the legs just don't want to push anymore so if you've stayed in the 25 or 28 all day the 32 is a godsend.