SRAM has released a range extender for the Powertrain e-bike motor, it packs in 250Wh of juice, weighs 1.5kg and costs £449. The Eagle Powertrain Range Extender 250Wh will work on any Powertrain-equipped bike, meaning Nukeproof, Transition, GasGas, Propain and Berria owners can amass 970Wh of power, should their bike pack the biggest 720Wh internal battery.

It’s a welcome addition to the Powertrain line-up because it also means bikes with the smaller 630Wh internal battery can have their range stretched to rival the likes of Specialized and Bosch.

Full charge can now be more than 100% on a Powertrain bike, thanks to the new range extender

Like all range extenders, it also offers flexibility to your ride, letting you tailor the range (and weight) of your bike to the route. This is pretty much essential if you’re opting for one of the best lightweight e-bikes on the market, but it’s also a sensible move for full power e-bike owners too.

SRAM Eagle Powertrain Range Extender 250Wh need to know

• 250Wh range extender for SRAM’s Powertrain e-bike motor
• Works with Nukeproof, Transition, GasGas, Propain and Berria bikes
• Y-cable for simultaneous charging of main battery and Range Extender
• Charge time of 1 hour 45 minutes, 1.5kg for the battery pack
• Switch between the Range Extender and a cage for standard water bottles
• Range visible up to 140% on the top tube display
• £449 for battery, £585 including all fittings

Snap on a bottle cage for water, or the range extender mount for more mileage

SRAM says the range extender only boosts the ride time of the bike in Range mode, while the faster Rally mode is supported just by the main Powertrain system battery. This means you won’t be able to stick the bike in its pokiest SRAM Rally mode and go hell for leather, which might actually prove to be a blessing because you can drain the range extender first, before ditching it in favour of a waterbottle. We’re guessing here, but it’s probably also necessary because small batteries can’t produce the high voltages required to power full fat e-bikes in their highest power modes.

With a Bosch range extender clipped to the Whyte E-Lyte 150 Works there’s still space higher up for a waterbottle

Choose drinking or pedalling

There are some slight problems with the modern range extender idea, chiefly you’ll have to choose between drinking and pedalling because the Powertrain Range Extender takes the place of a water bottle. Every bike but one suffers from this problem, so SRAM is not exactly alone here, with only Whyte managing to cram in both a rangy and a water bottle on its brilliant E-Lyte.

Buy the battery and you will also need to cost in a cable and mounts

It’s not a cheap way to boost a bike’s power either, because while the Powertrain Range Extender is price matched to the Bosch PowerMore 250Wh, the cable you need to actually plug it into your bike isn’t. You’ll need to add on another £110 for a cable (Bosch charges £30), £8 for a Snapframe to mount it, £18 for cable clips, and £13 for a dust cover (although this last addition isn’t strictly necessary). Add all that up and the Powertrain Range Extender is £585 all in.

It does sound like the cable and fitting system is a cut above the rest though, we’ve yet to try it but SRAM says the fitting is hassle free, which presumably means it’s quicker and easier to attach – a few seconds, it’s claimed. There are also three different cable lengths on offer, so you can ensure you get just the right amount of slack.

Who wouldnt want more riding time?!

The charge time is also pretty quick on the Powertrain Range Extender, a claimed 1 hour 45 minutes, to Bosch’s 3.2. Presumably this means it’s using a fast 8A charger, while Bosch uses either a 4A or 2A.