Cassettes... it's a minefield out there

[MissyR]

I am looking to change my cassette out for something that will help me with hills. I am currently on shimano 105 5800 11-28 but struggle greatly with hauling my ass up any hill. What is max size cassette I can use without having to change out my RD.

 

[Milkfloat]

I am looking to change my cassette out for something that will help me with hills. I am currently on shimano 105 5800 11-28 but struggle greatly with hauling my ass up any hill. What is max size cassette I can use without having to change out my RD.

Depends on the RD. What do you have?

 

[MissyR]

Sorry its a short cage or SS

 

[Milkfloat]

You may get away with a 30 or even if you are really lucky a 32, but you won't know unless someone else has tried it on the same frame. Worse case you would need a new RD, cassette and chain to get you to a 32.

 

[Ajax Bay]

You may find reading (skimming) this current thread worthwhile, indeed you may already have found it in a quick search before you posted. Most unlikely that a short cage (SS) even with the B screw right in will operate satisfactorily with a 32t, but other's MMV. Confirm you are already on a 50-34 compact chainset.

 

[Dogtrousers]

Figure out the required capacity of the mech (big ring + big sprocket) - (little ring + little sprocket). See if your mech can handle it: The techdoc for your mech will tell you the capacity of your mech and also the largest sprocket it can deal with.

Rear mechs are surprisingly cheap, so swapping a GS for an SS may not cost much.

But beware ... you could end up with quite a shopping list. New mech, new cassette, new chain, new gear cable, oh ... and what state are your chainrings in? And while you're at it why not replace the other cables too and ... and that bar tape looks a bit tatty ... and ... and.

 

[Ajax Bay]

Specs below, but many people seem to operate a 30T successfully. Overall capacity (as opposed to largest sprocket) may be an issue. Really don't need that 11T in fact a 13-30 cassette would be a best seller.

Shimano 105 -5800 11speed rear derailleur, SS, for low gear 28T
Specifications:

• 11-speed 105 wide link rear derailleur
• Advanced Wide Link design increases rigidity and shifting performance
• Super stiff for fast and accurate changes across the cassette
• Large 11 tooth pulleys increase service life and reduce noise
• Super light shift action
• Compatible with 11-speed drivetrains
• Maximum low sprocket 28 for SS - 32T for GS with double chainset
• Average weight 232 grams (GS)

 

[tincaman]

Go for a 5800 11-32, it will fit your short cage rear mech. I am also confirm for anyone interested that the medium cage will handle a 36T.
But be prepared to have to get a new chain as well, yours may end up too short. Cassette is £23-£24, chain is £14, all prices sourced from Merlin cycles.

 

[doog]

Id stick with a 30T......your 105 will defo take it with slight adjustment of the B screw and it to be fair it should get you up almost anything on a road bike.

 

[migrantwing]

30t fits my 5700 short cage RD fine with loads of room

 

[migrantwing]

Really don't need that 11T in fact a 13-30 cassette would be a best seller.

Most definitely.

 

[Smokin Joe]

Really don't need that 11T in fact a 13-30 cassette would be a best seller.

You ain't kidding. For most people an 11t sprocket is ridiculous, it has just become a bit of a fashionable macho thing.

 

[tincaman]

For 105 11speed, the next option from a 28T is the 32T.
The SS rear mech will take it, and as mentioned before, the B screw will probably have to be screwed right the way in.

 

[rusty bearing]

A short cage mech will run a 32 tooth cassette but it will 'burble' a bit. I changed to a long cage rear mech. Mrs bearing by a complete accident (she says) has a Dura Ace group set with 11-32 and long cage is not available which is how I know that the 32 is possible.

 

[Ajax Bay]

I have a long audax coming up with serious hills at the 100 mile point on Days 1 and 3 (of 75 hours) - Hardknott Day 1 and Rosedale Chimney Day 3. So have decided to try to manufacture a 12-30 cassette (9 speed) by buying an 11-30, removing the 11T (the 12T can be the 'new' outer one (has serrations)) and inserting a 13T from another used cassette (where the middle sprockets had worn). Will see how it goes. I may need to file off the wide spline on the 13T a bit to allow me to get orientation right to ensure the pick up from 12T to the new 13T shifts satisfactorily.
RD is a 105 RD-5500.
So instead of 11 12 14 16 18 20 23 26 30 I will have 12 13 14 16 18 20 23 26 30. With a 52T large chainwheel I'd be content with 13 14 15 16 etc (this would still give me a 108" top gear) but the bottom 7 sprockets are pinned: 14 16 18 20 23 26 30.