Unreleased Shimano 105 12-speed mechanical groupset spotted at Eurobike

We get an early glimpse as Shimano's first-ever mechanical 12-speed road bike groupset

Nick Pole

Published: June 25, 2023 at 11:35 am

The unreleased 12-speed Shimano 105 mechanical groupset has been spotted hiding in plain sight on the Corratec stand at Eurobike.

Though online leaks and the sighting of Shimano’s new GRX groupset have hinted at what’s to come, this is the first time we have laid eyes on the brand’s first-ever mechanical 12-speed road bike groupset. Our original story from 6 January runs below this update.

As the sighting comes before any official announcement from Shimano, we have no details on pricing, specs or weights. We have contacted Shimano for further information and will update this story if we hear back.

Curvacious new derailleur

New 105 12-speed R7100 rear derailleur
The derailleur looks very different to the outgoing R7000 rear derailleur. - Nick Pole

The design of the rear derailleur sees the biggest changes.

The outer plates are more curvacious than 105 R7000, with the outer plate bulging outward. This then flows smoothly into the P-knuckle (the lower knuckle on which the pulley plates pivot).

The design of the pulley cage diverges from 105 Di2 R7200, with a shorter spur kicking out from the rear of the lower pulley. The mechanical 12-speed 105 pulley cage also features a cutout at the top of the outer plate.

Compared to R7000, the cable barrel adjuster sits further back on an extended arm. The limit screws appear to still sit beneath this arm. The cable appears to clamp in approximately the same place.

Direct-mount is here to stay

12-speed 105 mechanical direct-mount rear view
Nick Pole

Shimano’s direct-mount derailleur design looks to have been dropped from the new GRX groupset and has been absent from the brand’s mountain bike derailleurs since 2018’s XTR M9100 launch.

However, in keeping with Dura-Ace Di2 R9200, Ultegra Di2 R8100 and 105 Di2 R7100, mechanical 12-speed 105 appears to stick with the standard.

Shimano’s direct-mount standard is claimed to create a stiffer interface between the frame and rear derailleur, improving shifting quality.

Unlike SRAM’s UDH standard, Shimano direct-mount has never really taken off. Despite this, its continued inclusion suggests the brand feels there is a future for the design.

Hoods unshrouded

New 105 12-speed hoods
The new 105 12-speed hoods look essentially identical to R7000/R7020. - Nick Pole

Unusually, Shimano’s new 12-speed 105 shifters have not adopted the same shrouded design introduced on its latest-generation Di2 shifters.

The shroud covers a repositioned pivot on Shimano’s Di2 groupsets and we had predicted 12-speed 105 mechanical would make a similar move.

In truth, the new 12-speed mechanical Shimano 105 hoods look virtually identical to the existing 105 R7000 hoods, though the guts of these will, of course, have been updated to accommodate the move to 12-speed.

105 Di2 sets the scene

New 12-speed 105 groupset, full shot
The new groupset is visually very similar to 105 Di2. - Nick Pole

As expected, certain components are shared across both electronic and mechanical versions of Shimano’s 105 groupsets.

New 105 12-speed mechanical calipers
Certain components are shared with 105 Di2, including the calipers. - Nick Pole

The brake callipers, crankset and cassette all look identical to those released alongside 105 Di2 R7100, and we’d be very surprised to see any new spec options released with the new mechanical groupset.


Original story continues below (06/01/23)

Information published on KHS’s website appears to confirm a mechanical version of Shimano 105 12-speed is on its way.

When Shimano launched the latest version of its third-tier groupset in June 2022, many were surprised to see the groupset manufacturer had only released an electronic version of 105.

While the new electronic groupset followed in the footsteps of Shimano Dura-Ace Di2 R9200 and Ultegra Di2 R8170 in going 12-speed, the move away from mechanical shifting seemed at odds with 105’s position as a more budget-friendly groupset option.

Notoriously tight-lipped, Shimano said nothing at the time about the possibility of a mechanical version of 105 Di2 R7100, despite speculation a mechanical version would be in the works.

However, the listing published on KHS’s website appears to confirm we can expect a mechanical version of 105 R7100 this year.

What do we know about Shimano 105 R7100 so far?

Specification for KHS Flite 700.
The specification shows 105 components that aren't currently in Shimano's range. - KHS

First reported by Bicycling, the listing on KHS for its 2024 Flite 700 showed a specification listing Shimano 105 R7100 derailleurs and ST-R7170 shifters.

Looking at the listing, we could see the cable running to the front derailleur, implying this is a mechanical rather than an electronic groupset.

The components look as if they’re from the previous Shimano 105 R7000 groupset, but the component names listed don’t currently exist in Shimano’s range.

The listing also showed an 11-36 cassette. The R7000 version of 105 could only fit cassettes up to 34 teeth.

Finally, the listing showed a 12-speed chain, and of course, the previous generation of 105 was an 11-speed drivetrain.

‘This is somewhat embarrassing’

Since the KHS listing was first reported, the brand has removed the Flite 700 listing from its website. The website address now leads to a “Page not Found” with the message 'This is somewhat embarrassing isn’t it?'.

BikeRadar has approached KHS to ask for comment, however we hadn't heard back at the time of publishing.

We speculate either KHS saw the reporting and is looking into what’s happened or Shimano has approached the brand and asked it to remove the listing for the time being.

What will the groupset be called (and will there be rim brakes)?

Shimano 105 rim brakes on the Giant TCR Advanced 2 road bike
Will we see rim brakes? - Russell Burton / Immediate Media

All previous-generation 11-speed 105 components were lumped under the R70XX moniker:

  • R7000 – 11-speed rim brake components
  • R7020 – 11-speed hydraulic disc brake components

Given Shimano follows predictable naming conventions for all of its products, we expect 12-speed 105 mechanical will follow the same pattern as 105 Di2:

  • R7100 – 12-speed rim brake components
  • R7120 – 12-speed hydraulic disc brake components
  • R7170 – 12-speed Di2 hydraulic disc brake components
  • R7150 – 12-speed Di2 electronic shifting components

Note that 12-speed 105 Di2 is not available in a rim brake variant. We expect there will also be no rim brake components available for mechanical 12-speed 105.

Rim brake-equipped bikes make up a very small part of the complete bike market these days. Given 105 is specced primarily by OEMs, it feels unlikely Shimano will look to serve this niche part of the market with a consumer-focused groupset.

For Shimano riders who swear by rim brakes, Ultegra or Dura-Ace has you covered.

What we expect from Shimano 105 12-speed mechanical

Dolan ADX Titanium 105 Di2 road bike
Shimano 105 mechanical will likely share much in common with its Di2 equivalent. - Russell Burton / Our Media

We expect the mechanical version of Shimano 105 12-speed to share much in common with its Di2 equivalent.

In keeping with previous-generation groupsets, Shimano will use the same crankset design and offer the same 50/34t configuration.

This is currently the only crankset available for Shimano 105 R7100, but Shimano has said a 52/36t version will be available at an unspecified date.

Elsewhere, we expect to see the same disc brake calipers with the bleed port on the outer side for easier access. Like the latest Dura-Ace and Ultegra calipers, these are said to retract 10 per cent further than previous Shimano disc brake calipers.

Rotors are likely to stay the same too, as are cassettes and the 12-speed chain.

Shimano will likely move the revised hood shape of the 105 Di2 shifters over to the mechanical version of 105, too.

How much will Shimano 105 12-speed mechanical cost?

Shimano 105 Di2 R7100 drivetrain
105 Di2 costs £1,730 / $1,890 / €1,869. - Shimano

Shimano 105 Di2 R7100 has a retail price of £1,730 / $1,890 / €1,869.

The mechanical version of the groupset will cost less than its electronic equivalent.

While there is no direct price comparison between Di2 and mechanical versions of 105 from previous generations of the groupset – this being the first Di2 version of 105 – we know mechanical versions of Shimano’s other groupsets have cost less than the Di2 equivalents.

This as-yet-unreleased groupset should sit between 10-speed mechanical Tiagra and 12-speed 105 Di2 in Shimano’s hierarchy. Therefore, the pricing should reflect this.

A full Shimano Tiagra 4720 groupset has an RRP of £749.99 / €869.99 / $917.99 / AU$1,343.98.

There’s a considerable step up to Shimano 105 R7100 Di2 at £1,730 / €2,006.80 / $2,117.52 / AU$3,100.76 for a complete groupset at full price.

Quite where its mechanical counterpart will slot in is anyone’s guess.

Given that mechanical Ultegra costs about half as much as its Di2 equivalent, it’s possible that 12-speed mechanical 105 will be closer to 10-speed Tiagra in price.