Like the idea of a 1x drivetrain, but worried about the lack of range and jumps between gears? Classified thinks that its new Powershift rear hub holds the answer, combining the ratios of a 2x system with the fast-shifting of hub gears and the clean design of a 1x setup – and we’ve had one in for review for the past few weeks.
Classified’s Powershift system was announced nearly two years ago and it has gradually been gaining momentum since then, specced by more brands all the time.
Check out our video (above) from the recent Sea Otter show to get a full rundown of the system from Classified and all-round cycling legend Tom Boonen, who is one of its backers. Skip to 7:58mins for all the Classified info.
The new Powershift hub uses a planetary 2x gear system that operates wirelessly and is powered by contactless energy transfer from the thru-axle. This effectively moves the functionality of the front derailleur into the rear hub. You still use a rear derailleur and a multi-speed cassette in the normal way, it’s just that there’s no need for two chainrings up front.
Classified says that the Powershift hub offers faster shifting than a front derailleur, it’s maintenance-free use, and you get the gear ratios you’d find on a normal double chainring setup.
The Powershift hub can be broken down into two main parts. The simple hub shell is much like any other hub shell and this houses the Smart Hub where we find all of the clever stuff. Here, an electronically actuated clockwork-like mechanism shifts between two gears “within 150 milliseconds under full load”, according to Classified.
The system works in much the same way as other internal gears, with one of the gears acting as a simple direct drive and the other gear giving a reduction to 70% of that.
For example, if you’re used to running 52/36-tooth chainrings then Classified recommends that you pick a 52 tooth chainring for this setup. The gearing that you would have with the Powershift would be that 52-tooth, while the reduction gear would give you the 36-tooth (technically it’d be a 36.4, but who’s counting?).
The system is powered by a rechargeable battery housed within the thru-axle. Classified says that the “Contactless Energy Transfer (CET) Technology wirelessly transfers energy for actuation via induction coils,” so you’ll need to use the specific thru-axle or you won’t be able to shift.
Packing all of this tech into the rear hub has meant that the Classified hub requires a proprietary cassette. Classified says that its cassettes – machined from solid blocks of cromo steel – offer “increased durability and lighter weight” than standard options.
The cassettes come in 11-27, 11-30, 11-32 and 11-34-tooth versions which, with the 2-speed Powershift hub provide 358%, 398%, 424% and 451% gear ranges (the gear range describes the difference between the bottom gear and top gear).
One of the main benefits of Powershift, Classified claims, is that it will shift “faster than anything on the market”. The shift takes just 0.15 seconds. On a double changing setup, shifting up into the big ring to attack – or bailing out into the little ring when you realise that the climb is pitching up again – takes longer than that.
You can also shift under load without the fear of dropping your chain. The only condition is that you’ll need to be doing less than 1,000 watts for shift to occur.
The durability and maintenance-free life of internal hub gears are two reasons why hub gears are so popular on utility and town bikes. Classified says that the Powershift hub “has an operational lifespan exceeding the lifespan of a bicycle’s internal systems, and it requires no maintenance.”
Classified doesn’t give an exact figure for the system’s battery life, stating that a fully charged thru-axle should give you three to six months of use. The thru-axle is rechargeable via a micro USB cable.
Classified says that a Powershift-equipped bike is the same weight or lighter than a bike with a bike fitted with a 2x electronic groupset and a traditional reference hub such as a DT Swiss 350.
“A bike equipped with Classified and 1x [Shimano] GRX Di2 weighs the same (+-10g) as a bike with a traditional 2x11 GRX Di2 groupset and a DT Swiss 350 hub,” says Classified.
“The weight of the replaced components (front derailleur, small chainring, traditional hub, thru axle and cassette) is approximately the same as the weight of the components offered by Classified.”
The expensive bit of the system can also, Classified claims, be swapped between different hub shells. In theory, that means that you could use one Powershift system in multiple wheelsets, provided they all have the Powershift hub shell.
In order to work with the Classified Powershift system your bike frame should have the following spec:
Classified cassettes are compatible with Shimano and SRAM 11-speed or 12-speed rear derailleurs, preferably with a clutch (ensure the maximum sprocket capacity of your rear derailleur covers the Classified cassette you’ve chosen, of course).
Both mechanical and electronic rear derailleurs are compatible with Classified cassettes.
A whole section of Classified’s website is devoted to compatibility so we’d suggest you head over there for more details.
Each includes a Classified handlebar unit and a satellite shift button for operating the system, and a cassette. Sprockets Cycles, for example, has them for sale at £2,299.99.
Now that we have the G30 wheel installed and have been getting the miles in, we’ll soon be releasing a video giving our initial thoughts on Classified Powershift. A full review will follow too.