[r-mm]

I bought a Shimano XT M786 10sp rear derailleur and goat link to convert my old Ellsworth Truth to 1x10.

I believe the frame has a 'standard mount' hanger and I am confused if the link which came with the shimano or the goat link is the correct part to attach the mech to the frame? When i bolt it up it rubs the cassette which is a 11-46.

 

[r-mm]

There are no interference issues when I put back the old eight speed 32 tooth cassette. I was aware of potential issues about shifting into the 46 tooth cog on the ten speed cassette but I have not read about issues mounting the derailer. I thought I would be safe with the goat link. Is this an issue with reusing the FH-M525 freehub? Do I need a 10sp freehub to move the cassette away from the derailer?

The old SRAM 9.0 Sl Shifter that was on the bike with the 8speed setup mounts fine with the new cassette.

 

[LyNx]

Hey r-mm, yeah, going to be hard to get that RD to work with a cassette with a 46t cassette, you would be much better off buying an 11spd RD to use with the 10spd shifer and cassette or just going 11spd. My current setup on my main ride is an 11spd XT RD paired to 10spd shifter and cassette and I really love it, much softer and smoother to me than a complete XT 11spd setup. I run expander cogs on my old 10spd cassettes, but only either 40 or 42t depending on wheel/tyre size being used.

 

[r-mm]

Thanks LyNx - I'm trying to understand why it is that this setup won't play nice. Is it because the XT 10sp is a "low profile" design that puts the shift cable arm back by the cog? Screenshot from shimano attached...

Is it the long cage xt8000 I'd be looking for?

 

[LyNx]

Yeah, the arm gets in the way on those. I tried using one with same WT Goatlink to run an SS/Trials wheel with 6 cogs, 36t big cog, but in the position most would be a 28t cog, in previous years using 9spd RDs, no problem except needing a longer B-limit screw, but with the new RD, it would hit the biggest cog. You don't need the long cage to run 1x, the GS works fine, or at least for me running a 42t and looks like I'd have no problem with chain take up/slack if I went bigger. I at first had the SGS RD and it worked fine, but it was so close to the ground that it got easily clogged with mud and debris on those sorts of rides.

Thanks LyNx - I'm trying to understand why it is that this setup won't play nice. Is it because the XT 10sp is a "low profile" design that puts the shift cable arm back by the cog? Screenshot from shimano attached...

Is it the long cage xt8000 I'd be looking for?

 

[the-one1]

Cage size don't matter. It's the placement of where the top pulley is at. On the 10 spd, it does not move out of the way, so you have to crank in the B screw. On the 11spd, the pulley moves out of the way when the derailleur is at the 46t.

 

[Harold]

That 10spd derailleur was not designed to work with a cassette that big.

The original design for that RD was for an 11-36 cassette max. Folks tweaked it to fit cassettes with a 42t big cog, mostly by replacing the cage that holds the pulleys so that the pulleys do what the-one1 said. Oneup components made these.

The 46t cog didn't show up until the 11spd generation, and Shimano's 11spd RD's are made to work with a 46t big cog out of the box. I'm really not sure what Sunrace was thinking putting a 46t cog on a 10spd cassette in all honesty, even though I have and like 2 of their 11-46 11spd cassettes. Maybe Sunrace had Lynx's setup in mind for this.

I've gotta wonder why you're bothering with 10spd at this point, rather than using 11spd. Shimano HG freehub bodies are the same from 8-11spd so you can install any of those drivetrains on your wheels.

 

[r-mm]

Thanks for explaining that. Im an architect by day, restore cars by night and find bike parts compatibility FAR more challenging than either.

I did not know 11sp would fit the hub and I just bought a whole mess of 10sp parts incl chain shifter cassette and derailer. It seems the fastest way to a solution would be the 11sp medium cage XT RD M8000?

If anyone wants to buy a discounted one day old 10sp XT and goat link lemme know