Force 1 to 1x12 AXS

[MrRobot]

Apologies for cross posting this from the road forum but I thought that there might be a few more 1by fans on the gravel forum ....

I curently run a complete 1x11 SRAM Force 1 rim brake groupset and would like to upgrade to 1x12 SRAM AXS.

Wolftooth claim their 110 BCD chain rings are compatible with the flat top 12 speed chain so in theory I should be able to keep my original Force 1 cranks and spider.

Would I have any chainline issues using one of these chainrings with the Force 1 cranks and spider?

Cheers

[kundica]

I'm not sure about the chainline with the Wolftooth chainring but Force 1 mechanical and Force 1 AXS have similar chainlines (45.5 vs 45). I run Wolftooth's direct mount Cinch flattop compatible chainring on my EC90 SL crank with AXS and it works great so if the chainline is good you'll be fine.

What gearing do you run on your current setup? When I initially upgraded to Force 1 AXS from Force 1 mechanical I planned to go 2x once AXS compatible 3rd party chainrings hit the market. I've been running the 10-33 cassette with a 38t or 42t chainring. This setup is fine for flat areas or CX but I wouldn't want to do any serious hills with it. This week I decided to swap the rear deraileur for Eagle instead of going 2x and run the Rotor 11-39 cassette on my road wheels with large range cassette on my gravel wheels. I mention this in case the 10-33 range isn't enough for you, you can go mullet and have more options.

[MrRobot]

Cheers for the advice

I currently run a Sram X-sync 44T with a SRAM 11-36. I find it very comfortable for my riding.

By my caluclations the 10-33 with a 40T should give me almost exactly the same gear range albeit with a spread more biased towards the bottom end, which is not ideal.

I had not considered Eagle with a Rotor cassette and 11-36 is available... Could I then use a standard eagle chain rather than the flat top chain?

Would using this chain then allow me to keep my existing SRAM front ring and std 11 speed rear hub body?

[kundica]

Yes. Use a 12 speed KMC chain which should work with your current chainring and the Rotor 12 speed cassettes use a standard Shimano hub.

The Rotor 11-36 and 11-39 both have single jumps for the first 5 gears. The AXS 10-33 has single for the first 6 but I find that I don't really use the 10t cog. The cassettes are a bit pricy but they're very light and the price might be offset by not upgrading your hub(depending on your wheels).

There's a lot of good info on the 3t blog in several posts from Gerard Vroomen who designed the Open and 3t bikes if you're interested. I'm installing the new derailleur and Rotor cassette this afternoon so I'll have some hands-on experience with it in the next day or two.

[kundica]

UPDATE: Installed the Rotor 11-39 cassette and Eagle AXS derailleur this weekend. At first, I had trouble getting it to shift correctly which was due to chain brand. I tried an X01 and 12 spd Campy chains but neither shifted correctly on the 12t and 33t gears. I spoke with Rotor and they said their cassettes are designed for use with KMC so I tried the KMC X12 chain and it works like a charm.

I'm also using the SRAM 11-50 cassette on a 2nd wheelset. I sized the chain to the larger cassette but used 1 linkset instead of 2 for smoother shifting on both cassettes using the same chain.

[NLC86]

UPDATE: Installed the Rotor 11-39 cassette and Eagle AXS derailleur this weekend. At first, I had trouble getting it to shift correctly which was due to chain brand. I tried an X01 and 12 spd Campy chains but neither shifted correctly on the 12t and 33t gears. I spoke with Rotor and they said their cassettes are designed for use with KMC so I tried the KMC X12 chain and it works like a charm.

I'm also using the SRAM 11-50 cassette on a 2nd wheelset. I sized the chain to the larger cassette but used 1 linkset instead of 2 for smoother shifting on both cassettes using the same chain.

Hi, how did you set up the b-gap and the limit screws with the Rotor 11-39?

[kundica]

UPDATE: Installed the Rotor 11-39 cassette and Eagle AXS derailleur this weekend. At first, I had trouble getting it to shift correctly which was due to chain brand. I tried an X01 and 12 spd Campy chains but neither shifted correctly on the 12t and 33t gears. I spoke with Rotor and they said their cassettes are designed for use with KMC so I tried the KMC X12 chain and it works like a charm.

I'm also using the SRAM 11-50 cassette on a 2nd wheelset. I sized the chain to the larger cassette but used 1 linkset instead of 2 for smoother shifting on both cassettes using the same chain.

Hi, how did you set up the b-gap and the limit screws with the Rotor 11-39?

You have to play around with it since sizing the chain to the 11-39 won't allow the cage to get close enough to use the bgap tool.

Sent from my GM1917 using Tapatalk

[NLC86]

UPDATE: Installed the Rotor 11-39 cassette and Eagle AXS derailleur this weekend. At first, I had trouble getting it to shift correctly which was due to chain brand. I tried an X01 and 12 spd Campy chains but neither shifted correctly on the 12t and 33t gears. I spoke with Rotor and they said their cassettes are designed for use with KMC so I tried the KMC X12 chain and it works like a charm.

I'm also using the SRAM 11-50 cassette on a 2nd wheelset. I sized the chain to the larger cassette but used 1 linkset instead of 2 for smoother shifting on both cassettes using the same chain.

Hi, how did you set up the b-gap and the limit screws with the Rotor 11-39?

You have to play around with it since sizing the chain to the 11-39 won't allow the cage to get close enough to use the bgap tool.

Sent from my GM1917 using Tapatalk

Thanks, I sized the chain using the standard method (2 linkset). Let's say that almost everything is smooth but not the 2nd cog (33t). I will try to size the chain with just one linkset. In any case, I guess the current configuration is pretty satisfying....at least for me.

What about the Force AXS + Garbaruk Cage? Do you think it works better than Eagle AXS on the Rotor 11-39?

[grover]

Throwing another option out there. Shimano are making their 12 speed XTR cassette in a 10-45 ratio. Too big? Shift quality probably way better than Rotor due to the cassette itself but also not as big a difference in tooth count versus the Eagle cassette for the Eagle derailleur. The problem is getting a chainring in a big enough size that is designed for the XTR hyperglide+ chain.