1X Drivetrain

[3WHELZ]

There are 1X Drivetrain discussions sprinkled throughout several threads. I am hoping to focus the discussion in this posting. This would include the use of elliptical and narrow-wide chainrings paired with the appropriate cassette.

I am currently debating whether to simplify my drivetrain from a two chainring Di2 10sp Dura-Ace to a 1X11 sp configuration.

Thanks, Dean

 

[Brad R]

I put a 1x11 on my T50.

I have a 40T NW elliptical chain ring and an 11-46 cassette.

As I got conditioned, I found that I want a higher top end and that I generally lose traction when I am on something steep enough to need the 46 (15 to 20% grade for me.)

I may get a bigger chainring.

I considered a double or triple with a closely spaced cassette but decided I wanted to try the simplicity of the 1x11.

I assumed that I would be comfortable with a wide enough cadence range to handle the 20% jumps at the high end. I find that I often wish that I had gone for the double or triple with a narrow cassette because my most comfortable cadence range is narrower than I expected and I find myself having to push harder on my knees than I want or accepting that I will go slower than I would with tighter gear spacing.

Make sure you are comfortable with the step sizes you will have before you make the jump.

 

[DavidCH]

I have been so impressed with my last little project that only cost me $700 that I bought these oval 1 speed chainring from alibaba . I will let you know how it goes when they arrive. This crit bike build has a one speed round chainring and it hugs.

On my V I can be sure that the chain will come off at some point in 40km off my rotor qxl and I've got sick of having to stop and putting it back on. So I thought I would give it a try.

 

[bladderhead]

I have XX1 11sp cassette and a 42t w/n oval chainwheel from Garbaruk. My chain has never jumped off.

 

[DavidCH]

On my Vendetta. I have a one speed drive chain using one of those stone oval rings. It works well but I do miss the QXL Rotor chain ring. I just have been reading about the rear deurallier Shimano ultrgra Rx that has an in built clutch. It's meant for rough terrain chain chop but I suspect it would make a Rotor QXL ring more reliable with regards to chain drop. On a typical 30 mile ride my chain would come off twice, usually with a high cadence. Anyone out there got experience with one of these rear deuralliers?

 

[bladderhead]

4000 miles and no chain-drop. And I have a home-made bar-end friction shifter. According to Sram there are two things that stop chain-drop. One is the clutch. The other is the wide-narrow ring. They say it has to be easy for the chain to jump off a double because this makes it easy to change gear, and everybody manufactures chainrings that lose the chain easily.

 

[rx7mark]

I am quite happy 90% of the time with my 1x setup on my T50. I also use a Stone elliptical narrow wide 42t chain ring with a 11-42 Shimano cassette and a SRAM GX rd. With a 26inch wheelset, I can climb to the limits of my traction and balance. Low gear is about 6mph @90rpm. At the high end I spin out at 28-29mph. In about 600 miles I have never had a chain drop, love that!

I also appreciated the simpler maintenance & setup, cheaper cost, and the lighter weight front end. I was able to buy a single chainring 155mm aluminum crank with 110bcd off the shelf for only $120.

The 10% I don't like is the gear spacing, of course. I find myself occaisionaly wishing for a closer gear spacing, especially at the high end, and I would love one more higher gear, but don't really need it.

Overall a great compromise for me and the way I ride my bike.

Mark

 

[Brad R]

I am quite happy 90% of the time with my 1x setup on my T50. I also use a s
Stone elliptical narrow wide 42t chain ring with a 11-42 Shimano cassette and a SRAM GX rd. With a 26inch wheeler, I can climb to the limits of my traction and balance. Low gear is about 6mph @90rpm. At the high end I spin out at 28-29mph. In about 600 miles I have never had a chain drop, love that!

I also appreciated the simpler maintenance & setup, cheaper cost, and the lighter weight front end. I was able to buy a single chainring 155mm aluminum crank with 110bcd off the shelf for only $120.

The 10% I don't like is the gear spacing, of course. I find myself occaisionaly wishing for a closer gear spacing, especially at the high end, and I would love one more higher gear, but don't really need it.

Overall a great compromise for me and the way I ride my bike.

Mark

I have a 44T elliptical wide narrow chainring with an 11-46 cassette. I just changed from a 40T elliptical. I really like the extra 10% at the top end. I also have never had the chain drop.
The 44/13 tooth cog gives 88 gear inches which is between the 80 of the 40/13 and the 94 of the 40/11. I find the 88 gear inches is now my most common cruising gear on level ground without a headwind.

 

[rx7mark]

I have a 44T elliptical wide narrow chainring with an 11-46 cassette. I just changed from a 40T elliptical. I really like the extra 10% at the top end. I also have never had the chain drop.
The 44/13 tooth cog gives 88 gear inches which is between the 80 of the 40/13 and the 94 of the 40/11. I find the 88 gear inches is now my most common cruising gear on level ground without a headwind.

I have been considering a Wolf 11-49 conversion with a 48t elliptical chainring, which would give me gearing similar to yours.

Just have to decide if the change is worth the price? I really don't need it, but ...

Mark

 

[Bill K]

On my Vendetta. I have a one speed drive chain using one of those stone oval rings. It works well but I do miss the QXL Rotor chain ring. I just have been reading about the rear deurallier Shimano ultrgra Rx that has an in built clutch. It's meant for rough terrain chain chop but I suspect it would make a Rotor QXL ring more reliable with regards to chain drop. On a typical 30 mile ride my chain would come off twice, usually with a high cadence. Anyone out there got experience with one of these rear deuralliers?

I am running 1 x 11 on the S40 with the Shimano RD-M8050-GS DI2 rear derailleur with 11-speed 11/46 cassette.
This is the mountain bike version which includes a clutch.
Sometimes I forget to engage the clutch (it has an on-off lever). The clutch does not seem to make a difference for me.

My first configuration was with a Sugino 44-tooth track chainring. Chain line was about 54 mm (to match the Rohloff I used to have on the bike).
The chain would derail several times on most rides (every 10 or 15 miles or so). Always at high cadence.
The problem was the bad chain line.

I now have a Rotor QXL-36 chainring on the inner ring of a (different) double crank. It never derails.

BTW, for anyone considering using mountain DI2 derailleurs: you are stuck with 1 x 11. DI2 currently does not support mixed derailleur types. Both FD and RD must be either road or mountain. And there is no way I know of to mount a mountain FD to the post-mount stem.

 

[DavidCH]

home-made bar-end friction shifter

Impressive... any chance of a photo?

 

[bladderhead]

My friction shifter. I got a chainring-and-cog pair. The chainring one was a friction shifter but it had a really small lever-throw, about a right-angle, so it did not pull enough slack. The cog one had built-in clicks, for 10sp. I took them to bits and combined them. They were surprisingly complicated inside. The new lever still did not pull enough slack, so I use a Jtek Shiftmate. I am still amazed how well this all works.