I want to swap my Shimano Dura-Ace 11-28 cassette for an 11-40. Or an 11-42. What should I buy to make sure it works well? Thanks! 11-speed
- Thread starter ladfors
- Start date
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Is your rear mech Dura Ace as well. If so I understand 11 speed DA can only go up to a 30 tooth sprocket.
Sea of vapours
Guru
- Location
- Clapham, Yorkshire Dales
If your rear derailleur is R9100 Dura Ace then you could use one of these: https://www.wolftoothcomponents.com/products/roadlink-dm
That would move the derailleur back/out a little and enable it to clear the largest sprocket on an 11-40 cassette. Your chain will be slightly too long in small / small, but that's not a huge issue provided you don't actually pedal in it. If possible, find someone who's done this to advise you face-to-face.
That would move the derailleur back/out a little and enable it to clear the largest sprocket on an 11-40 cassette. Your chain will be slightly too long in small / small, but that's not a huge issue provided you don't actually pedal in it. If possible, find someone who's done this to advise you face-to-face.
Ajax Bay
Guru
- Location
- East Devon
To answer this Q properly we need to know what the chainset is eg 50t-34t and what the rear derailleur is including cage type. Measure the distance between the two pulley wheel axles in mm, for a bonus point. 40t is way out of spec: just saying.
raleighnut
Legendary Member
- Location
- One of the 'Elite'
Why ?
Ajax Bay
Guru
- Location
- East Devon
Yours not to reason why. Yours but to do and advise.
Really not worth relitigating the need (or lack of) for dinner plates.
Adds zero value.
Really not worth relitigating the need (or lack of) for dinner plates.
Adds zero value.
Thanks! I am 75 years , 85 kilos=187 pund. I am planning to do alp d'huez.....probably better to use a compact chains 50-34 and Ultegra RD-R8000-GS (Medium Cage). + Shimano Ultegra CS-HG800-11 +chain?
Ajax Bay
Guru
- Location
- East Devon
Shimano-grx-fc-rx600-double-11-speed-chainset-46-30t
and an 11-34 or 11-32 cassette (<£50).
What RD have you currently? (as asked) - is it the "Ultegra RD-R8000-GS (Medium Cage)"? GS will manage a 34t.
and an 11-34 or 11-32 cassette (<£50).
What RD have you currently? (as asked) - is it the "Ultegra RD-R8000-GS (Medium Cage)"? GS will manage a 34t.
MadMalx
Senior Member
- Location
- Settle, Yorkshire Dales
If you need to ask random people on the internet what gears you need, the answer is almost certainly ‘as low as you can achieve’.
You will need at least a medium cage derailleur to cope with a 34 biggest cog on your cassette, and a compact chainset (34 tooth small ring). To cope with a bigger cassette & longer chain you will (probably) need a wolftooth (mentioned above), or a grx rear derailleur. The latter will probably get you up to a 40tooth cog, but it is beyond the official spec. I’ve run this with a 50-34 up front with no problems.
I’m 10 years younger, 15kg lighter and ride hills totalling 4000m+ almost every week. My lowest gear is 30 (front) 32 (back) and I use it frequently. The chainset & front detailleur are grx to handle the small chainring.
Edit: apologies, the op wasn’t asking what gears were needed, rather if a 40 could be fitted.
You will need at least a medium cage derailleur to cope with a 34 biggest cog on your cassette, and a compact chainset (34 tooth small ring). To cope with a bigger cassette & longer chain you will (probably) need a wolftooth (mentioned above), or a grx rear derailleur. The latter will probably get you up to a 40tooth cog, but it is beyond the official spec. I’ve run this with a 50-34 up front with no problems.
I’m 10 years younger, 15kg lighter and ride hills totalling 4000m+ almost every week. My lowest gear is 30 (front) 32 (back) and I use it frequently. The chainset & front detailleur are grx to handle the small chainring.
Edit: apologies, the op wasn’t asking what gears were needed, rather if a 40 could be fitted.
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