Expander gears now up to 50t

cycleclinic

I used to think the jumps in MTB cassettes were not bad but that was 10 years ago when 11-32t was the standard offering. I have since spent too much time on road bikes with 12-25T cassettes and now an 11-32T has jumps which seam a bit too big but tollerable. The 11-36T give me range I just never use (bear in mind my lowest gear is 28:32T and I never use that). Even if I had a 40T outer ring on 1x12 a 40:50T gear is so low I be quicker walking but most will have a 36T ring which is even worse.

This is where I struggle. 12 speed would have been a good idea if SRAM offered a 10-40T cassette with smaller jumps in cadence but alas I don't think that cassette is possible without increasing dropout width yet again to maintain reasonable spokes bracing angles.

supersonic

At the minute of course the Eagle is only an option at the very high end. It will filter down to some of their other groups I imagine eventually. A lot of people will probably opt for the shark tooth thing if they feel they need more range with a 1x system rather than splash out on all this. That chainset though, 465g claimed with ring, that might interest a few to use in existing set ups too.

rockmonkeysc

This is how 12 speed cassettes look on a bike

cycleclinic

That cassette is coming next year.

Angus Young

RockmonkeySC wrote:

This is how 12 speed cassettes look on a bike

And I'd still have to get off and push now and again.

Herdwick

Angus Young wrote:

RockmonkeySC wrote:

[img]https://scontent-lhr3-1.<span class="skimlinks-unlinked">xx.fbcdn.net/hphotos-xfp1/t31.0-8/fr/cp0/e15/q65/12909463_657395297732635_6742648681858203901_o.jpg?efg=eyJpIjoidCJ9</span>[/img]

This is how 12 speed cassettes look on a bike

And I'd still have to get off and push now and again.

Give them one more year, they will figure something out

swod1

Herdwick wrote:

Angus Young wrote:

RockmonkeySC wrote:

[img]https://scontent-lhr3-1.<span class="skimlinks-unlinked">xx.fbcdn.net/hphotos-xfp1/t31.0-8/fr/cp0/e15/q65/12909463_657395297732635_6742648681858203901_o.jpg?efg=eyJpIjoidCJ9</span>[/img]

This is how 12 speed cassettes look on a bike

And I'd still have to get off and push now and again.

Give them one more year, they will figure something out

Yeah an ebike lol

Going back to the new sram eagle group looks to have improved chain ring tooth profile load spread over more teeth at top of chain ring and derailleur cage tweaks.

However i bet the gear shifts are still clunky compared with xt/xtr.

Do we think 50t is now the limit or will they experiment with more 52, 55t?

As this is going to be pricey i think people will just get xt 11-46 and compromise.

The Rookie

The bigger the largest sprocket the closer the mech gets to hitting something you don't want it to hit, I'm not convinced about the need for huge sprockets to be honest, I'm a not that fit nearly 50 year old and been riding 1x9 with an 11-34 for over two years without it being a problem, longer steeper hills are hard work though so I am going to swap to an 11-40 ten speed and chain the chainring to use the spread for both a higher top and lower bottom gear.

Herdwick

swod1 wrote:

Going back to the new sram eagle group looks to have improved chain ring tooth profile load spread over more teeth at top of chain ring and derailleur cage tweaks.

At any given time one tooth at a time holds the load no matter how the chainrings tooth profile is designed, or there is a feature but did not understand it yet

The Rookie wrote:

The bigger the largest sprocket the closer the mech gets to hitting something you don't want it to hit,

the cage looks close to the medium length cages used on the 1x11 ders, so 27.5 will be a compromise and they will make a 28.3 wheel size now for extra clearance... Get ready

The Rookie

The chain is engaged on all the teeth, it has the same pitch as the teeth, ok that theory and there will be some tolerances so it's not perfect, but it's certainly not on just one.

The derailleur is below the biggest sprocket, bigger sprocket the lower it is, also the mech cage has to long enough to give the capacity, more capacity the longer the cage has to be as a minimum.

rockmonkeysc

It will share the load across roughly a quater of the teeth on the sprocket. That may change with wear.

Herdwick

The Rookie wrote:

The chain is engaged on all the teeth, it has the same pitch as the teeth, ok that theory and there will be some tolerances so it's not perfect, but it's certainly not on just one.

Yes that's obvious but do a simple test, get on the bike stomp on your pedal holding the rear brake and try to shake the chain on the chain ring, you will see that the chain is 'loose' except at the point where the first vertical tooth is engeged,
This is due to tolerances and stretching of the chain,