Shimano unveils 105 R7100 mechanical – a 12-speed road groupset for less than £1,000

Shimano has announced the release of 105 R7100, its first 12-speed mechanical road bike groupset.

Pitched at an 'affordable' price of roughly £990/$1,190/€1,180, 105 R7100 mechanical costs around £740/$700/€690 less than the Di2 version.

Having spotted the Shimano 105 R7100 groupset in the wild at Eurobike earlier this year, this launch confirms the new groupset is essentially a cable-actuated version of the brand's 105 Di2 R7150 electronic groupset.

As with Shimano’s previous-generation road groupsets, this sees non-shifting components – such as chains, cassettes, cranksets and brakes – shared across both the mechanical and electronic groupsets.

This launch, then, brings new, 12-speed mechanical rear and front derailleurs, plus updated shifters.

The rest of the groupset components are direct ports from the existing electronic groupset.

Like 105 Di2 R7150, there are no rim brake components – 105 R7100 is only compatible with hydraulic disc brakes.

Elsewhere – and before we get into the detail on 105 R7100 – there's also a new Shimano GRX gravel groupset. You can read our full Shimano GRX RX820 review for the verdict on that.

Mechanical shifting for road bikes is back in the conversation

With Shimano having not launched a new mechanical road bike groupset since the 11-speed 105 R7000 in 2019, some were lamenting the apparent demise of high-end mechanical groupsets.

Fortunately, though, it seems Shimano hasn’t forgotten about those who prefer mechanical drivetrains.

In fact, Shimano is pitching 105 R7100 at those “looking for reliable, easy-to-maintain componentry at an affordable price”.

It also cites a key advantage of mechanical groupsets over electronic ones – you’ll never need to charge it or worry about battery levels.

Given 105 R7100 shares all non-shifting components with its Di2 cousin, the gearing options and ranges are identical.

As with Shimano’s other 12-speed groupsets, 105 R7100 cassettes stick with an 11t smallest cog and retain compatibility with existing 11-speed Shimano HG freehub bodies.

Shimano is coy on whether there have been any specific improvements to shifting speed or quality, compared to the previous-generation, 105 R7000 groupset.

When pressed on the subject, it simply said “R7100 adheres to Shimano’s own high standards for shifting performance”.

Shimano 105 RD-R7100 rear derailleur

The part that sees the most significant update is the new rear derailleur.

Shimano doesn’t list any specific improvements to shifting speed or quality for the RD-R7100 rear derailleur, but the headline new feature is it can shift across 12, rather than 11, cassette cogs.

Visually, it departs from the previous RD-R7000 rear derailleur, gaining a flattened body and the same 105 branding from the Di2 R7150 rear derailleur.

The derailleur cage has also been updated, although this part isn't a straight port from the Di2 version – with the mechanical cage appearing to have more material cut from the outer plate, perhaps shaving off a few more grams.

As with 105 Di2 R7150, Shimano has dropped a short-cage rear derailleur option, offering just a single, medium-length derailleur cage instead.

As a result, the RD-R7100 rear derailleur is compatible with 11-34 and 11-36t Shimano HG cassettes.

Officially, the RD-R7100 rear derailleur isn’t compatible with the tighter 11-30t cassettes available at the Ultegra or Dura-Ace level.

The RD-R7100 rear derailleur has a claimed weight of 249g and costs £59.99/$64.99/€61.99.

Shimano 105 FD-R7100 front derailleur

As with the rear derailleur, Shimano isn’t claiming any particular improvements to shifting performance for the new FD-R7100 front derailleur.

The FD-R7100 isn’t a direct port from the previous-generation groupset, however, because Shimano says it has been updated to work “perfectly” with the new 11-36t cassette option.

There are some minor aesthetic changes too.

Officially, it’s only compatible with the 50-34 and 52-36t chainring combinations Shimano offers at the 105 level.

Shimano claims a braze-on FD-R7100 front derailleur weighs 96g and it costs £41.99/$46.99/€49.99.

Shimano ST-R7120 hydraulic disc brake set (shifters and calipers)

Shimano says the new mechanical shift and brake levers have been updated to work with the 105 BR-R7170 hydraulic disc brake calipers (which launched with 105 Di2 R7150).

These calipers have 10 per cent wider pad spacing compared to the outgoing BR-R7070 ones, as well as the updated bleed port location on the outward-facing side of each caliper.

The right-hand shifter is naturally updated with 12-speed shifting capabilities, but changes beyond that are (again) minor.

The overall shape of the hoods, brake levers and shifter paddles is practically identical at a glance, for example.

For its part, Shimano says ergonomics have been “refined”, while the brake lever action is now “lighter” and “smoother” than before.

Shimano also says the lever reach – the distance from the handlebar or brake hood to the brake lever – has been reduced, though it hasn’t specified by how much.

A set of ST-R7120 shifters have a claimed weight of 612g, while the BR-R7170 hydraulic disc brake calipers are claimed to weigh 267g.

Together, they cost £599.98/$709.98/€639.98.

It’s worth noting these weights don’t account for brake hoses or gear cables and housing, however.

Shimano 105 FC-R7100 crankset

The Shimano FC-R7100 crankset is a direct carry-over from the 105 Di2 R7150 groupset.

It uses Shimano’s Hollowtech II construction, with a 4-bolt 110mm Bolt Circle Diameter (BCD).

It’s available with two chainring combinations, 50-34 and 52-36t, and five crank length options – 160, 165, 170, 172.5 and 175mm.

The FC-R7100 crankset costs £159.99/$179.99/€182.99, and is claimed to weigh 754g (50-34t, no crank length given).

When we weighed our 105 Di2 R7150 groupset, the 172.5mm crankset (with 50-34t chainrings) tipped our scales at 767g, though.

Shimano 105 CS-R7101-12 cassette

As with the crankset, the cassette is also ported straight from the 105 Di2 groupset.

It features 12 cogs and there are two ranges available – 11-34 and 11-36t.

The cogs use Shimano’s Hyperglide shaping, which is claimed to improve shift quality, but don’t get the Hyperglide+ tech (an evolution of the Hyperglide cog shaping that's claimed to improve shifting speed by a third), as seen on the latest Ultegra and Dura-Ace cassettes.

The cassettes are compatible with 11-speed Shimano HG freehubs, and Shimano claims an 11-34t cassette weighs 361g (the 11-34t cassette we received with 105 Di2 weighed 360g).

The 11-34t cassette costs £69.99/$65.99/€76.99, but the 11-36t option is a little more expensive at £84.99/$87.99/€99.95.

Shimano SM-RT70 brake rotors

The SM-RT70 brake rotors are not only a carry-over from 105 Di2, but also from the previous-generation 105 R7020 mechanical groupset.

In fact, these rotors were first developed for Shimano’s SLX M7000 mountain bike groupset, which launched back in 2016.

They use a Center Lock design, and are priced at £29.99/$45.99/€65.98 per rotor.

Shimano gives a claimed weight of 121g for a 140mm rotor and 133g for a 160mm rotor. In total, the 140/160mm pair that came with our 105 Di2 test groupset weighed 253g.

Shimano CN-M7100 chain

Shimano’s press release for 105 R7100 doesn’t mention it, but the new mechanical groupset will use the same CN-M7100 chain that 105 Di2 R7150 employs.

As with Shimano’s other 12-speed road groupsets, this chain is ported straight over from Shimano’s equivalent mountain bike groupset – which in this case is SLX M7100.

According to Shimano’s website, the CN-M7100 has a claimed weight of 252g, including a quick-link, and costs £34.99/$32.99/€38.95.

When we inspected the CN-M7100 chain that arrived with our 105 Di2 groupset, though, it weighed 278g.

Shimano 105 R7100 groupset weight and prices

Totting up the claimed weights for individual parts gives a total weight of 2,845g, though that doesn’t include gear cables or housing.

In any case, that’s 105g lighter than the actual weight – 2,950g – of our 105 Di2 R7150 test groupset.

Once you account for brake hoses and gear cables, it’s likely to be on a par with its electronic equivalent, though.

Doing the same for prices, however, gives a total of £986.91/$1,192.91/€1,182.85 for a full 105 R7100 mechanical groupset (with a braze-on front derailleur and the 11-34t cassette option).

Compared to 105 Di2, which has an RRP of around £1,730/$1,890/€1,869 (depending on spec), the new mechanical groupset is roughly £740/$700/€690 cheaper.

As always with Shimano, though, RRPs don’t necessarily reflect real-world prices, so the gap may be different at your preferred retailer.

Here’s a breakdown of how each individual part in the groupset stacks up in terms of claimed weight and price.