Upgrading from Shimano 11 speed to 12 speed, anything I need to check?

johnmcl7

I have a bike with a Shimano 105 groupset and an 11 speed 11-32 cassette, I'm considering changing to 105 Di2 with the Shimano 11-34 cassette. As far as I can see this should work fine and wouldn't need a new freehub but thought I'd better double check before going any further.

Thanks

super_davo

You don't need a new freehub. The 12 speed cassettes / hubs have a new spline pattern but it is backwards compatible; I'm using mine with an 11 speed hub and all fine.

As long as your frame is Di2 compatible you'll be fine, and even then because the shifters are wireless you may be able to make something work even if it isn't officially.

daniel_b

Are the 105 shifters optional wireless as well?

I know DA is.

super_davo

daniel_b said:

Are the 105 shifters optional wireless as well?

I know DA is.

Yep. Wired mechs to internal battery, wireless shifters, same as DA and Ultegra.

Hence I think you can probably bodge to fit a fair amount of "mechanical only" frames if you wanted (obvs do so at your own risk etc.)

ugo.santalucia

Anyone knows if they can be operated as 1x ? In other words, no front mech at all… and maybe no left di2 shifter either… or no battery in it

johnmcl7

super_davo said:

You don't need a new freehub. The 12 speed cassettes / hubs have a new spline pattern but it is backwards compatible; I'm using mine with an 11 speed hub and all fine.

As long as your frame is Di2 compatible you'll be fine, and even then because the shifters are wireless you may be able to make something work even if it isn't officially.

It's a 2017 Trek Domane 5 SL Disc (https://archive.trekbikes.com/us/en/2017/Trek/domane_sl_5_disc#/us/en/2017/Trek/domane_sl_5_disc/details), I think the frame is Di2 compatible and has a battery mount under the bottle holder but will need to check.

PMark

Another potential option is getting SRAM axs, but use with shimano crank 12 speed and cassette (as is completely wireless). It isn’t officially supported of course, but there are lots on YouTube that say that setup works.

ugo.santalucia

for a 1x setup, is it the case that all I would need is a right di2 shifter, a battery and a rear derailleur? Would that work?

super_davo

Possibly but it is disc brake only. Which probably rules you out, and you'd need a left hydraulic brake unit if it didn't

ugo.santalucia

I have seen 8150 in rim brake version…

super_davo

ugo.santalucia said:

I have seen 8150 in rim brake version…

Ok... Interested where, as all the press at the release stated "Death to the rim brake" e.g. https://road.cc/content/feature/5-things-we-hate-about-shimano-105-di2-295293.

Of course since that article was written 105 mechanical has been released, but I've not seen anything on rim brakes.

super_davo

Sorry you said 8150.. that is Ultegra which does have a rim brake version. Just not 105.

akh

ugo.santalucia said:

for a 1x setup, is it the case that all I would need is a right di2 shifter, a battery and a rear derailleur? Would that work?

You can definitely pair a pair of levers to a rear derailleur and shift without a front derailleur, not sure about just a single shifter. I recall the app wants you to sync both levers to the rear derailleur during set up. I doubt Shimano would allow it to work.

akh

daniel_b said:

Are the 105 shifters optional wireless as well?

I know DA is.

105 levers are not optionally wireless, they're only wireless. Only Ultergra and Dura Ace can be run wired or wireless. With 105 levers there's no port for satellite shifters, no 'hidden' buttons, and the port they do have is only for firmware updates. Shimano's own Di2 general guide confirms this too, but better shifting is a better website:

https://bettershifting.com/component/105-disc-brake-wireless-dual-control-lever-st-r7170/

**edited for clarity**

johnmcl7

akh said:

daniel_b said:

Are the 105 shifters optional wireless as well?

I know DA is.

105 levers are not optionally wireless, they're only wireless. Only Ultergra and Dura Ace can be run wired or wireless. With 105 levers there's no port for satellite shifters, no 'hidden' buttons, and the port they do have is only for firmware updates. Shimano's own Di2 general guide confirms this too, but better shifting is a better website:

https://bettershifting.com/component/105-disc-brake-wireless-dual-control-lever-st-r7170/

**edited for clarity**

Interesting, I'd somehow missed this when looking at the R7170 vs R8170 shifters. So does that mean I could use the R600 hill climb shifters with the R8170 shifter but not the R7170?

me-109

Have you looked at the Chinese electronic options? Have seen that there are one or two YT vids reviewing it/them. Thinks it's Sensah. Maybe L-Too (sp?)? Microshift might even have joined the party now. Having said that, a used 'known quantity' might be a better option.

super_davo

me-109 said:

Have you looked at the Chinese electronic options? Have seen that there are one or two YT vids reviewing it/them. Thinks it's Sensah. Maybe L-Too (sp?)? Microshift might even have joined the party now. Having said that, a used 'known quantity' might be a better option.

There is L-Twoo E-rx- but it is also disc only.

And at UK retailer discount prices 105 Di2 costs exactly the same once you factor in chainset, chain and cassette. It looks interesting but IMO it will need to undercut it by a margin to become a compelling option

akh

johnmcl7 said:

akh said:

Interesting, I'd somehow missed this when looking at the R7170 vs R8170 shifters. So does that mean I could use the R600 hill climb shifters with the R8170 shifter but not the R7170?

That shifter won't work out of the box as the plugs are smaller on the 12 speed levers, no idea if you can modify it to fit or if Shimano have locked it out in some way. There are dedicated 12 speed satellite shifters (both climbing and sprint), albeit with a very different design on the climbing shifters, check out better shifting for more detailed info than I can provide.

johnmcl7

akh said:

johnmcl7 said:

akh said:

Interesting, I'd somehow missed this when looking at the R7170 vs R8170 shifters. So does that mean I could use the R600 hill climb shifters with the R8170 shifter but not the R7170?

That shifter won't work out of the box as the plugs are smaller on the 12 speed levers, no idea if you can modify it to fit or if Shimano have locked it out in some way. There are dedicated 12 speed satellite shifters (both climbing and sprint), albeit with a very different design on the climbing shifters, check out better shifting for more detailed info than I can provide.

I've had a dig through the Shimano compatibility guide and I think you're right the old ones wouldn't work, instead it would need the new SW-RS801-S shifters.