Cotic’s new e-bike stays true to its signature steel frame style of 21 years, and uses a wholly UK-built frame to minimise ecological impact and maximise build quality. Mounting the battery externally looks outdated, but brings a host of low-weight, high-practicality benefits too. It’s retro aesthetics and premium pricing mean it’s had a roasting in the online comments. So are the trolls right, or does it Deliveroo where it really matters – on the trail – enough to stand among the best e-bikes on the market? I, for one, wanted to find out.

Old school meets new school: Cotic’s Rocket e-bike goes back to the future

Cotic Rocket e-bike need to know

• Steel-framed trail/enduro e-bike
• Designed and hand-built in the UK
• 150mm rear suspension travel
• MX wheels
• Shimano EP801 motor with choice of external batteries (stock bike comes with 418Wh)
• Frameset, complete bike or custom build options starting at £6,350

Cotic’s floating trunnion mount takes out side loadings and improves shock sensitivity and durability.

Frame and geometry

At first glance the plastic-encased Shimano battery pack bolted onto the slim steel down tube undoubtedly gives the Rocket a ‘retro/JustEat/DIY’ look depending on how rude you want to be. However, designer/founder Cy Turner has spent several years sweating the details of this Marmite design, through several prototypes (including a full-alloy Cotic frame with internal battery) and those efforts became clear when I got up close. The down tube is a custom Reynolds pipe with a DH-strength rating to handle the weight of the battery even on the sendiest of bike park days. The steel mount for the Shimano motor is also totally custom, saving over a kilo compared to off-the-shelf designs.

Seriously neat welding sits alongside rather more Meccano-like bolt and braces engineering.

The chassis is a collaboration with other UK companies to minimise environmental impact and maximise build quality. The mainframe is meticulously (the welds are truly sensational) built by Five Land up in Scotland. Coal Bikes produces the alloy chainstays in Nottinghamshire, using machined parts from Rideworks in Coventry, who also makes the linkage. Bear Frame Supplies makes the pivot bosses and axles, just down the road from Cotic in the Peak District. A bespoke offside motor cover and cable management system is 3D-printed by 76 Projects in Cambridgeshire, and used to keep the Shimano motor neat and well-protected.

The layout leaves room for your choice of external batteries.

While the vertical shock and ‘Rocklink’ suspension look similar to the original Cotic Hemlock FS bike, the kinematics are very close to Cotic’s current Droplink range. 15mm pivot thru-axles and Enduro and SKF bearings are mostly proven pieces from previous bikes too. However, a unique floating roller bearing mount for the trunnion style shock has been added to stop side loads getting to the causing premature wear – it’s a clever bit of innovation from Cotic. Paint is applied in the UK with an à la carte custom option alongside the copper, crimson and topaz stock choices.

Shimano’s EP801 will hang off the bottom of production Rockets. From this angle, the integration is rather agricultural.

In other words, in many ways this bike couldn’t be further away from the e-bike conversion kit jalopy some have compared it to. And you’d hope so, given the frameset, motor and battery module option cost a not-insignificant £6,350. This is artisan rather than Ali Express, even if some of the areas around the motor, particularly, are agricultural in their lack of acknowledgement to form.

A button on the battery powers-on the Rocket.

Steel might be old-school as a material, but for Cotic that tradition does not extend to the geometry. Hence the Rocket is loosely based around the brand’s self-propelled Jeht trail bike, with a 64.5º head angle and 482mm reach when using a 150mm fork on the size C3. However, the effective seat angle on the e-bike is steeper, at around 76º depending on seat height. The back end is also pulled out to 456mm (from 448mm) and the 40mm bottom bracket drop is lower (it was 33mm). The Jeht only has 140mm travel as well, while the Rocket has 150mm at the rear and can run a 150mm or 160mm travel fork (I’ve ridden it with both).

Magura brakes are standard on the Gold build.

Components

The sample bike I rode was something of a mash-up in terms of specification, but production bikes will be offered in two different build styles – Trail and Enduro – when the bike goes on sale in spring 2025. These are based around either 150 or 160mm forks, at two different levels – Gold (Lyrik/Zeb) and Platinum (Fox Factory 36/38). Gold bikes also get Magura brakes and a basic Cotic finishing kit, while Platinum bikes hop-up to Hope brakes and XTR rather than XT on the uber premium £10,999 Platinum trail build. There are loads of custom options via a pull down menu, but you can also mix and match your existing kit to a frame and motor module if you want. Safety regs mean Cotic have to build it for you in-house – no DIY option.

Get up close and personal and there’s lots of cool detailing on the Rocket.

While the development bike I rode was powered by an older Shimano EP8 motor, all production bikes will have the latest Shimano EP801. That opens up the potential to use a Di2 gear set with all the latest Auto Shift and Free Shift technology, as well as the latest Shimano firmware update that unlocks adjustable overrun and loads more support. While bikes will come as standard with the 418Wh Shimano battery I tested, you can opt for 504Wh for £80 more or 630Wh for a £180 bump. At just 50g more weight for 86Wh more power, the 504Wh is definitely the sweet spot cell too. Second batteries are priced at £400, £500 and £600 respectively, which is £70 off RRP and matches most online prices. Fitted as standard is a Datatag, which is a nice touch in case the unthinkable happens.

Cotic has shunned the cookie-cutter template used by most e-bikes, and put ride quality at the top of the priority list.

How it rides

Let’s not dodge the obvious here. There are two big things to talk about when it comes to the Cotic Rocket. How it rides and why it looks like it does. You don’t look at a bike while you’re riding it though, so let’s talk trail vibes first. If you know your geo numbers you won’t be surprised the Rocket feels planted and secure straight away, just as you’d expect from a modern trail e-bike. The steeper seat angle (compared to standard Cotics) is a noticeable advantage on the steeper climbs, all of which the Shimano motor takes in its stride. The longer back end also levers the wheel onto the ground with more authority, so I was never short of grip through the mullet back wheel. While the standard 160mm cranks help prevent pedals from catching on rocks, logs and ledges on the way up.

Even with the old EP8 motor, missing the latest firmware update, Guy was impressed with the Cotic’s climbing ability.

Climbing

The smaller diameter rear wheel also means a quicker turn in, accelerated further by the low bottom bracket, so it’s a bike I could really get my knee into. While you might think having the rear wheel tucked right in would be better for manoeuvrability – and it is in some situations, particularly when popping the front wheel up – the long rear end and resulting body weight centralisation helped me really loosen up my hips on snaking descents. Enough to let me wriggle ruts and surf drifts with way more steez and poise than my stiff, senior citizen’s skeleton normally does.

Supple suspension and a compliant ride makes for a bike that doesn’t bite back.

Descending

That’s not just good geo either. The supple, compliant, traction micro-managing ride of steel frames has been celebrated ever since the first big alloy tubed bikes made it obvious what harshness was. Cotic has 21 years of experience making the most of steel’s assets, so while the down tube is a beefy pipe that was strong enough for Neko Mullalay’s Frameworks DH prototypes, and the custom Ovalform top tube is taut by steel standards, it’s still got far more flow than an oversize alloy frame. That’s not an anecdotal statement either, as I rode Cotic’s first alloy e-bike sample and it was a bluntly solid and unyielding lump of a bike. FEA (Finite Element Analysis – basically structural stress and stiffness –results also show that the Rocket frame is several magnitudes more flexible and forgiving than the stiffest oversized bikes run through the same tests.

Hanging out the back end on the Cotic Rocket.

That means the Cotic feels warm and animal rather than coldly mineral in the way I experienced the trail through it. And as anyone who’s watched Pierron and his Commencal pals flow effortlessly through the sketchiest World Cup sections – while other DH teams saw chunks out of their swingarm braces to try and compete – will know, smooth, Tai Chi tubing can also be seriously fast. The crisply concise, accurately damped and multi-adjustable Cane Creek shock on it’s ultra sensitive roller bearings keeps things impressively calm at all speeds too. The RockLink suspension also increases anti-squat over previous DropLink bikes, so it can handle bigger rock slaps better and stays more stable when the extra motor torque kicks in. More sprung mass than unsprung mass in the suspension equation being the foundation that all this extra comfort is built off.

Cotic has ploughed its own furrow with the Rocket e-bike, and Guy believes it is all the better for it.

The decision to mount the battery externally doesn’t just keep Cotic’s signature ride feel alive. It also saves significant weight in both battery, mount, and even an alloy down tube compared to an internal mount (although the energy density of these old Shimano batteries is considerably worse than the latest units from Bosch, TQ, and others – Ed). A removable battery also simplifies charging and travel and lets you ‘hot swap’ to a second battery to extend range far more than a small ‘booster’ battery can. The external battery keeps the internal electrics that are normally the Achilles heel of e-bike reliability to a minimum. On/off switch and recharging ports are both on the battery itself, not the bike, so it’s only the wires from the bar display, remote switch and rear wheel that run through the frame. Having said all that, the plastic shoe box battery is undeniably ugly and out of place among the slim tubes and exquisite welding. Cy deliberately didn’t go down the custom battery or camouflaging bag (there is a Restrap frame pack coming) route for cost and convenient access/removal reasons. However, I’d definitely be getting busy with a sticker kit, or crafting some kind of Steampunk boiler brasswork onto the battery if I had a Rocket myself. And that’s not so far fetched…