Can 1x become 2x ?

[eddy]

I have seen many threads on whether you can convert 2x to 1x by, but I want to go the other way.

 

I have an 11spd XT 1x upgrade set spare and want to use it on a frankenbuild that already has a 2x crankset and FD I'd like to retain.

 

Is there anything that would prevent me from using the 1x RD and cassette on this build or should I look for someone who wants to "upgrade" to 1x and swap out ?

[BaGearA]

Yes I've seen it Done, you'll likely need a new crank and then obviously the shifter and derailleur

 

 

 

Back in 11spd days Shimano had A few 2x11 groups that were made intentionally that way

[Eddy Gordo]

I am pretty sure that you can. Just see what the require chainring sizes are for the rear derailleur

[eddy]

I am pretty sure that you can. Just see what the require chainring sizes are for the rear derailleur

 

Does the RD not concern itself with max and minimum range ?

 

So if I can run, say a 34 chainring and a 50 largest cog at the back, I should be able to run a 50 chainring and a 34 at the back and whatever the small ring gives me ?

[bertusras]

Does the RD not concern itself with max and minimum range ?

 

So if I can run, say a 34 chainring and a 50 largest cog at the back, I should be able to run a 50 chainring and a 34 at the back and whatever the small ring gives me ?

 

This is just me, but I don't think that's how it works. Best would be to look up the actual manual for your rear derailleur which will give you what you need.

 

https://bike.shimano.com/en-AU/product/component/deorext-m8000/RD-M8000-GS.html

 

or 

 

https://bike.shimano.com/en-AU/product/component/deorext-m8000/RD-M8000-SGS.html

 

 Depending whether you have the normal or long-cage version. Normal only gives you a 10T front difference (50/40), whereas the long-cage gives you 18T difference (50/32). So maybe you can run a 50/34 with the long-cage.

 

Edit: There is also the total capacity thing which I've never understood...

 

And there are also limits on the low end (granny gear) which seems to be 40T for either option.

Edited February 16, 2021 by bertusras

[Eddy Gordo]

This is just me, but I don't think that's how it works. Best would be to look up the actual manual for your rear derailleur which will give you what you need.

 

https://bike.shimano.com/en-AU/product/component/deorext-m8000/RD-M8000-GS.html

 

or 

 

https://bike.shimano.com/en-AU/product/component/deorext-m8000/RD-M8000-SGS.html

 

 Depending whether you have the normal or long-cage version. Normal only gives you a 10T front difference (50/40), whereas the long-cage gives you 18T difference (50/32). So maybe you can run a 50/34 with the long-cage.

 

Edit: There is also the total capacity thing which I've never understood...

 

And there are also limits on the low end (granny gear) which seems to be 40T for either option.

Along this lines yes. Especially where the big ring is concerned. If you gonna run a 44t for example, then you will most likely break something trying to climb the rear derailleur to 50t. So maybe a 36t and a 30 or 28t chainrings upfront with your 111/10 50t cassette.

[eddy]

 

 

https://bike.shimano.com/en-AU/product/component/deorext-m8000/RD-M8000-SGS.html

 

 Depending whether you have the normal or long-cage version. Normal only gives you a 10T front difference (50/40), whereas the long-cage gives you 18T difference (50/32). So maybe you can run a 50/34 with the long-cage.

 

Edit: There is also the total capacity thing which I've never understood...

 

And there are also limits on the low end (granny gear) which seems to be 40T for either option.

 

Excellent, thank you.

 

It is a long cage RD which can seemingly be used as 2x (and even 3x) within limits.

 

I have a 50/34 chainring and seemingly I can use this with up to a 40  low sprocket.

 

So, now to see if building another bike is at all a sensible idea...

[Jewbacca]

Excellent, thank you.

 

It is a long cage RD which can seemingly be used as 2x (and even 3x) within limits.

 

I have a 50/34 chainring and seemingly I can use this with up to a 40  low sprocket.

 

So, now to see if building another bike is at all a sensible idea...

It is the BEST idea.......

[dasilvarsa]

It's Better to Get a Full Groupset To Make Sure that everything is compatible.

 

https://bike.shimano.com/en-US/product/component/deore-xt-m8100.html

 

https://bike.shimano.com/en-AU/product/component/deorext-m8000.html

 

Some Configs Require a Rear Hub Rework.

[Zawillow]

Hi Eddy,

 

I did it and it was the best decision I could have made. I have a 11x M8000 long cage RD with a 38/24 front chain ring setup. Rear cassette is an 11/42 - you won't need more than that. For races like the Trans Baviaans and K2C the big granny and long high gear are great. 

 

Only issue I have is that my 38/24 chain ring is a SRAM compatible direct mount setup from Lyne components and unfortunately they no longer produce them. Still looking for an alternative that doesn't require a new crank.

[bertusras]

I think Eddy is building some sort of gravel frankenbike and already has a 50/34 crank that he wants to use, which is why I haven't suggest a gravel specific 46/36 crankset either (which is what I've got) with an 11-36 at the back, giving me a 1:1 ratio in my lowest gear (which was manageable when I was still fit and strong, but a 40T at the rear would probably be better).

[Eddy Gordo]

It's Better to Get a Full Groupset To Make Sure that everything is compatible.

 

https://bike.shimano.com/en-US/product/component/deore-xt-m8100.html

 

https://bike.shimano.com/en-AU/product/component/deorext-m8000.html

 

Some Configs Require a Rear Hub Rework.

what do yo mean?

[Eddy Gordo]

Hi Eddy,

 

I did it and it was the best decision I could have made. I have a 11x M8000 long cage RD with a 38/24 front chain ring setup. Rear cassette is an 11/42 - you won't need more than that. For races like the Trans Baviaans and K2C the big granny and long high gear are great. 

 

Only issue I have is that my 38/24 chain ring is a SRAM compatible direct mount setup from Lyne components and unfortunately they no longer produce them. Still looking for an alternative that doesn't require a new crank.

After sunday's wet ride, I am now thinking even more about the idea I had last year. Which is to convert the ht to rigid fork. 650b x 48 tyres and a 2 x 10 system as this will be easiest. I have the chainrings, just need a FD and shifter. I also want to keep the straight bars. Then late last year I started riding the HT about 2 to 3 times a week. I like the xfusion fork I have, and I can lock it out to make it completely rigid. Now toying with another wheelset maybe for the cx/roadie plus tyres.

[Eddy Gordo]

I think Eddy is building some sort of gravel frankenbike and already has a 50/34 crank that he wants to use, which is why I haven't suggest a gravel specific 46/36 crankset either (which is what I've got) with an 11-36 at the back, giving me a 1:1 ratio in my lowest gear (which was manageable when I was still fit and strong, but a 40T at the rear would probably be better).

I am running 32/ 42 and was thinking of adding just a bigger chainring. Will only use the smaller 3 ratios on the cassette with the big ring anyway. But thats just me. Now to find a money tree to fund this idea

[eddy]

I think Eddy is building some sort of gravel frankenbike and already has a 50/34 crank that he wants to use

Spot on. A nice Sram Red one on a Niner RLT steel frame....

[marshace]

I have seen many threads on whether you can convert 2x to 1x by, but I want to go the other way.

 

I have an 11spd XT 1x upgrade set spare and want to use it on a frankenbuild that already has a 2x crankset and FD I'd like to retain.

 

Is there anything that would prevent me from using the 1x RD and cassette on this build or should I look for someone who wants to "upgrade" to 1x and swap out ?

No problem, should work fine.  Front and rear mechs and shifters work independently.