There are plenty of e-bike conversion kits designed to turn your existing bicycle electric, but most involve at least a bit of wrenching. Spiny 2 takes a different approach, using a removable friction-drive system that can apparently snap onto your bike in just three seconds.
Now let me start by saying that this is a crowdfunding project on Kickstarter, so it’s a “buyer beware” situation. My long-time readers will know I have a rule about crowdfunding campaigns. I don’t cover them unless they either A) come from a company that has a track record of delivering products in the past, or B) I personally test out the product in advance to confirm it’s legitimate and works. In this case, I haven’t personally tested the Spiny 2 e-bike kit, but the brand does appear to have delivered hundreds of their previous version of the kit, so this isn’t a brand new, fly-by-night company.
The newly unveiled second-generation system combines its motor and battery into a compact 2.2 kg (4.9 lb) package. Once the mounting hardware and sensors are initially installed on the bike, the entire drive unit can be clicked into place before a ride and removed afterward.
It’s a friction drive kit, which isn’t the most elegant way to drive an e-bike, but it does get the job done quickly and simply.
That could be particularly useful for riders who want to keep the feel of their favorite pedal bike, but occasionally want a little electric help.
Instead of replacing a wheel or integrating with the drivetrain, Spiny 2 uses a roller that contacts the rear tire. Cadence and speed sensors detect when the rider begins pedaling, at which point the motor moves against the tire and begins providing assistance in around 0.25 seconds. Stop pedaling and the roller lifts away again, allowing the bike to roll without additional motor drag.
Keeping the whole kit street lega, the US version is rated at 250W nominal but can produce up to 750W of peak power and assist riders up to 20 mph (32 km/h). Canadian models peak at 500W, while versions intended for most other markets are limited to 250W and 25 km/h (15.5 mph).
A 266Wh battery is built into the removable unit, with Spiny claiming up to 90 km (56 miles) of range under ideal conditions. As always with e-bike range figures – especially one that ambitious from a relatively small battery – expect real-world range to depend heavily on assist level, terrain, rider weight, and speed. Suffice it to say though that unless you’re doing pro-level pedaling by yourself, the 266Wh battery isn’t going to net normal folks like you and me anywhere close to 56 miles of range on average day.
There are five pedal-assist levels controlled through a smartphone app or optional Bluetooth handlebar remote. Charging is handled via USB-C PD, while the unit carries an IP65 weather-resistance rating. That USB-C charging is perhaps one of the nicest features on the whole kit, allowing convenient recharging from a typical laptop charger or even a powerbank, and helping the kit join a very limited club of USB-C rechargable e-bikes.
Compatibility is fairly broad, including many road, city, hybrid, and touring bikes with either rim or disc brakes. Adapters are also available for some tighter-clearance bikes and Bromptons, though rear-suspension bicycles are excluded.
There are some limitations, with a major one being that you can’t operate a normal rear fender (though the higher floating style rear fenders should likely still work).
Spiny 2 recently launched on Kickstarter, with deliveries currently estimated for April 2027.
As with any crowdfunded hardware product, those delivery dates aren’t guarantees. But if Spiny can deliver on its promises, the ability to electrify your existing bike for Monday’s commute and turn it back into a normal lightweight bicycle three seconds later is certainly an interesting proposition.
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