Groupset News

[Crash217]

Forgive my lackluster knowledge/understanding in advance, I’ve read a few things but still can’t quite come to a conclusion on my own.

On the new RX12 derailuer from LTWoo, it lists a total capacity of 37t.  Would this be capable of working on a 9-46 cassette with a 40t crank ring? Or does the capacity refer to largest cassette gear it would fit with?  Perhaps a derailuer drop bracket would be needed? 

I’m planning on getting this groupset (or a Sensah if their hydraulics hit first and are more appropriate) to build myself a gravel bike mullet setup.

[acedeuce802]

Total capacity refers to the amount of slack the cage can take up.  For a 1x, it's max vs min cog, a 9-46t would need 37t capacity.  For a 2x example, an 11-32t with 50/34 chainrings would need (32-11)+(50-34) = (21)+(16) = 37t as well.  What you need to find out is the max cog size.  I would guess that since max cog size isn't listed (in the descriptions I looked up) and it's usually paired with 11-30t or 11-34t cassettes, that it's unlikely to work well with a 46t max cog.  I would rather find a rear derailleur with same pull ratio than use a big drop bracket.

[Crash217]

Thank you for the clear explanation.

[Flying Trunk Monkey]

To add to what acedeuce802 stated... RD's are also spec'd w/ a min cog size. I'd be cautious of using an 11t min cog spec RD with a 9t small cog unless you have prior knowledge of it working. In some cases an after market cage can be swapped onto a given RD to make it work with particular cassettes.   

Total capacity refers to the amount of slack the cage can take up.  For a 1x, it's max vs min cog, a 9-46t would need 37t capacity.  For a 2x example, an 11-32t with 50/34 chainrings would need (32-11)+(50-34) = (21)+(16) = 37t as well.  What you need to find out is the max cog size.  I would guess that since max cog size isn't listed (in the descriptions I looked up) and it's usually paired with 11-30t or 11-34t cassettes, that it's unlikely to work well with a 46t max cog.  I would rather find a rear derailleur with same pull ratio than use a big drop bracket.

[Zomb1e]

To add to what acedeuce802 stated... RD's are also spec'd w/ a min cog size. I'd be cautious of using an 11t min cog spec RD with a 9t small cog unless you have prior knowledge of it working. In some cases an after market cage can be swapped onto a given RD to make it work with particular cassettes.

2 cogs are definitely a very small difference for derailleur to stop working properly. As an example from mtb world: Shimano Deore rd-m5100 (11 sp) and rd-m6100 (12 sp) are exactly the same derailleurs construction-wise, but first one is specified for 11-51 cassette, and second - for 10-51.

[Flying Trunk Monkey]

Sram and Shimano are pretty conservative when it comes to spec'ing their components. That said, the RD scenario you cited was most likely a part that was optimized for 11t min cog that would then obviously work with a 12t. It's probably not the best example of something working outside its intended box.

I'd agree that 2t is a fairly small change in larger cogs but the difference between a 11t and a 9t is 22%, the difference between a 40t and a 42t is 5%. The difference in diameter between 11t and 9t is not "very small" relative to the size of the parts.

AFAIK, nobody makes an RD spec'd for 9t but manufactures like E13 knew what they had to work with when making a cassette that was designed for a 10t min. Like I said above, Sram and Shimano spec things conservatively enough that pushing things a little bit usually works out. For example, you can typically squeeze a few extra teeth in Shimano's capacity spec as well as usually get away with an extra tooth or two on the max cog size (sometimes by using a longer B screw).

One of my concerns with the scenario in question would be the amount of chain wrap on the 9t cog. It may work OK but wear could be a factor. That wear may or may not be acceptable depending on the individual. The cassettes that would allow such a scenario definitely aren't cheap.

[Queen of Skulls]

So I just read that shimano and sram have different set up for the index system? That sram works with sensah but not with shimano? But ltwoo and mirconew do work with shimano? But I have seen people mix the set ups. Like I was hoping to mix some micronew shifters with a empire rear.  Is that not do able? I like the interface of simple up down shifting.  Well I ordered some for my cheepo bike. I might up grade the 2x7 set up later.  and move every thing to my  1994 fuji marlborough special and go more gravel less mtb.  Anyways does it not work?

[Zomb1e]

That said, the RD scenario you cited was most likely a part that was optimized for 11t min cog that would then obviously work with a 12t.

10T, not 12T

[jonathanf2]

So I just read that shimano and sram have different set up for the index system? That sram works with sensah but not with shimano? But ltwoo and mirconew do work with shimano? But I have seen people mix the set ups. Like I was hoping to mix some micronew shifters with a empire rear.  Is that not do able? I like the interface of simple up down shifting.  Well I ordered some for my cheepo bike. I might up grade the 2x7 set up later.  and move every thing to my  1994 fuji marlborough special and go more gravel less mtb.  Anyways does it not work?

I messaged Trace Velo awhile back and he mentioned L-Twoo follows campy cable pull? Sensah has a line-up of shifters dedicated just for Shimano cable pull such as the Team Pro 11-speed shifters (and others with various names). The Sensah Empire and SRX shifters follow the SRAM cable pull ratio.

[Queen of Skulls]

I messaged Trace Velo awhile back and he mentioned L-Twoo follows campy cable pull? Sensah has a line-up of shifters dedicated just for Shimano cable pull such as the Team Pro 11-speed shifters (and others with various names). The Sensah Empire and SRX shifters follow the SRAM cable pull ratio.

Ok, So if I end up liking the micronew shifters and want to upgrade, 105 it is.

[raisinberry777]

There's a bunch of news hiding in what looks like plain sight in Ltwoo's updated catalogue:

http://www.ltwoo.com/en/col.jsp?id=175

On the MTB side, there's a new 'T' series of shifters/derailleurs with clutch rear derailleurs. These are across the range, going from 8-13 speed. There's also the semi-electronic shifters as has already been shown.





For gravel, there's the new shifter shape available in 1x12, with brake calipers (as has been leaked previously). There's also a new rear derailleur with a clutch that comes over from the MTB line, but has been redesigned to take a barrel adjuster which is across the range from 9-12 speed. All other components remain the same.



On the road, the new shifters are available in a 2x12 version, with aluminium or carbon blades.



No separate brake caliper listed so I assume it's the same as the gravel one. No other new road components, and the new lever shape is only seen on the 2x12 hydraulic content, everything else remains the same.

[StiffWeenies]

S-Ride are also working on hydraulic drop levers


unsure if they plan to go into Road 2x or if it is just meant to pair with their 1x gravel RD

[Queen of Skulls]

Why can they just do a di2 meets sram style shifters. wired  and wireless. I mean if you have a swappable battery box you can easily add on a wired function.  Just in case. and the you still need wireless connectivity for computers. Its literally just a wireless protocol.   You can also have like and I2c or serial connection via wire.  All which run a servo to push pull in changing gears.  One could literally build a basic system with like a stm32 chip. linear servo. I really don't know why shimano's and srams systems are sooooo over priced.and why chinese companies dont have a system out yet.   Like the parts needed are maybe $30 worth of electronics. at the very most. I dont know how they are $1500 over the standard groupset.

Anyways I cant wait for cheaper chinese groupsets.

[lilbigmacky]

An actually decent chiner mtb shifter would be pretty awesome. Hopefully it's not another disappointment.

[pecampbe]

There's a bunch of news hiding in what looks like plain sight in Ltwoo's updated catalogue:

http://www.ltwoo.com/en/col.jsp?id=175

On the MTB side, there's a new 'T' series of shifters/derailleurs with clutch rear derailleurs. These are across the range, going from 8-13 speed. There's also the semi-electronic shifters as has already been shown.





For gravel, there's the new shifter shape available in 1x12, with brake calipers (as has been leaked previously). There's also a new rear derailleur with a clutch that comes over from the MTB line, but has been redesigned to take a barrel adjuster which is across the range from 9-12 speed. All other components remain the same.



On the road, the new shifters are available in a 2x12 version, with aluminium or carbon blades.



No separate brake caliper listed so I assume it's the same as the gravel one. No other new road components, and the new lever shape is only seen on the 2x12 hydraulic content, everything else remains the same.

Can't wait to see when this becomes available and the pricing.