New XT.

[The Duckmeister]

Shimano doesn't publish this info in tech docs?

No.

They do produce "compatibility charts" but typically they're on the conservative side, with such suggestions like 8 & 9-sp derailleurs & shifters can't be mixed around, which we know for a fact is completely compatible.

 

[pharmaboy]

11-sp. chain is a poofteenth narrower. The difference may be within the tolerance of the tooth widths. Try it & see.

Be the same as the difference between sram 11 and 10 I'd imagine - people use 10s chains on sram 11 no problems. So a poofteenth would be an accurate descriptor


Surely the new asymmetrical BCD is to allow removing and fitting a chainring without removing the crank?

 

[c3024446]

If it is the same pull ratio, 11 spd will only require a cassette and a shifter

 

[moorey]

If it is the same pull ratio, 11 spd will only require a cassette and a shifter

If cassette width is same between 10/11sp, how can pull ratio be the same?

edit. Read that wrong. As you were.

 

[The Duckmeister]

Be the same as the difference between sram 11 and 10 I'd imagine - people use 10s chains on sram 11 no problems.

Yeah, that's using a wider chain on bits designed for narrower. The question was could you use a narrower chain on a ring designed for the slightly wider chain? I haven't met a N/W ring in the wild to study its tolerances, so I can't tell you if there's enough freedom when used with the correct chain to allow running a narrower one without jamming on the teeth.

 

[The Duckmeister]

Surely the new asymmetrical BCD is to allow removing and fitting a chainring without removing the crank?

Doubt it, you can do that with normal BCDs too.

Shimano use the same design for their four-arm road cranks too. Their "engineering reasoning" is that the individual spider arms are loaded differently at different crank arm angles, so they're angled accordingly. Can't say I've had any problem with normal cranks....

 

[Shadow Puppet]

The cassette is wider, so the derailleur needs to move further. It should be able to cover it because the limit screws when wound out allow considerably more travel than the width of the cassette it's designed for. The uncertainty is the leverage ratio: does the derailleur move the right distance for the amount of cable pulled by the shifter?

Using the current derailleur with a 42T cog out back results in needing a longer b-screw and screws up shifting performance too much for my liking. Using the OneUp RAD cage has made things almost perfect though.

 

[anthonyma]

Yep, but then they went & buggered it up when they went 10-sp, even though the cassette is virtually the same width as 8 & 9-sp. They changed the leverage ratio so it pulled a different amount of cable to achieve the same overall derailleur movement. What hasn't been determined yet is if 11-sp uses the same leverage ratio as 10-sp, or if it's something different again.

I'm sure they had a technical reason why it changed for 10 speed and cross-compatibility simply wasn't part of the engineering brief. 8 and 9 speed shows that it can be done and therefore it could be done again if the engineers were told that was a priority. The obvious outstanding question, as you say, is whether they did.

I'm going to guess that the pull ratio is the same as the current 11-speed XTR and that it should therefore only require testing with a 10 speed rear derailleur on an XTR drivetrain.

 

[The Duckmeister]

XTR & XT 11-sp. will have the same pull ratio - all groups within a given "speed" range are fully cross-compatible*. So yes, if you have an 11-sp. XTR group to play with, your experiments will be valid for XT.

I believe the change in ratio for 10-sp. was to give a more consistent feel across the cassette. I'm not 100% certain of the validity, but I have read suggestions that the ratio actually varies through the range to help reduce the "heaviness" in shifting that increases toward the bigger sprockets.

*Disregarding little details like splitting cranks & rings... they have been known to differ.

 

[cobba]

People are mixing 10 & 11 speed Shimano parts.

http://forums.mtbr.com/drivetrain-s...-m786-rear-11-speed-m8000-shifter-963288.html

http://forums.mtbr.com/drivetrain-s...d-m9000-works-10-speed-drivetrain-947611.html

 

[c3024446]

People are mixing 10 & 11 speed Shimano parts.

http://forums.mtbr.com/drivetrain-s...-m786-rear-11-speed-m8000-shifter-963288.html

http://forums.mtbr.com/drivetrain-s...d-m9000-works-10-speed-drivetrain-947611.html

Well, looks like I'll be able to run 11 spd XT with a 11-42T! Already have a rad cage on my 10spd XTR Shadow+......Just need a shifter and a cassette

 

[Pastavore]

Well, looks like I'll be able to run 11 spd XT with a 11-42T! Already have a rad cage on my 10spd XTR Shadow+......Just need a shifter and a cassette

That is awesome, I'll be more than happy with 11 speed 11-40.

 

[GazzaPops]

I'm doing my happy dance, on the inside. I was going to go down the one-up 42 + 16 and the rad cage option when my current drive train dies but instead I'll get the full xt set up, less the cranks of course.
I'll only lose one ratio at the top end and I only use it going down hill on the tar!
I can't wait to go 1x again!

 

[Ivan]

That is awesome, I'll be more than happy with 11 speed 11-40.

I have the XTR 11-40, and I will buy and XT 11-42 when it comes out for the extra range. It's nice when you bonk to have a low bailout gear.

 

[Knuckles]

I have the XTR 11-40, and I will buy and XT 11-42 when it comes out for the extra range. It's nice when you bonk to have a low bailout gear.

Jeezus, I struggle to ride and eat a cliff bar at the same time, but you can get on the job while riding. Maybe there's more to these bitch cogs than I thought....

 

[rowdyflat]

Assymetrical cranks just cos they can , just to be arseholes so any aftermarket manufacturers of chainrings have more difficulty.
Its not as though spiders/cranks have been breaking regularly.

 

[Minlak]

Will be buying as soon as can get reliable stock I think the cranks are sexy as. Can pass down my current stuff to the missus.

 

[JTmofo]

I see wolftooth have launched a nw ring for M9000 and M8000 cranks. I would nt be too worried about being tied into shimano branded rings.

 

[pharmaboy]

I see wolftooth have launched a nw ring for M9000 and M8000 cranks. I would nt be too worried about being tied into shimano branded rings.

The wonders of modern CNC software and hardware

All you need is for the market to be big enough for the product in order to be arsed to distribute it. Must admit though , isn't 104bcd the simplest ever std - my mates with bloody sram cranksets are all ever so slightly different (OEM cranks)

 

[Knuckles]

The wonders of modern CNC software and hardware

All you need is for the market to be big enough for the product in order to be arsed to distribute it. Must admit though , isn't 104bcd the simplest ever std - my mates with bloody sram cranksets are all ever so slightly different (OEM cranks)

Yes the s1000 120bcd is a pain in the arse, but the S1400 104bcd or direct mount are the nuts. DM in particular.

The thing that does my head in is the complete lack of any NW variation by shimano. Furrymuff if it was just SRAM, you could claim, yeah nah, it's just a gimmick. But Shirley the massive after market range and the endless tweaks on the concept should give them some idea of its importance.