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Hacking your e-bike for extra speed risks spoiling everyone's fun

Biktrix Juggernaut Classic
E-bikes like the Biktrix Juggernaut Classic are limited to 15.5mph with power assistance, for good reason (Image credit: Biktrix)

People who modify their electric bikes for extra speed are putting them at risk of being classed as motorbikes rather than bicycles, according to industry experts. That would be a huge change, and would mean that e-bikes could no longer be ridden on cycle paths, would require a license and insurance, and in some countries could only be used by riders over 21.

In the UK, EU, and many US states, the maximum assisted speed for an e-bike is 15.5mph. Beyond that speed, the motor will cut out and you'll have to put in all the work yourself. E-bikes with a higher assist limit exist, but in most territories they are only be legal to ride on private land.

Some riders get around the rules by fitting delimiters to regular e-bikes, either manually or by fitting a third-party 'tuning kit'. Not only does this make your e-bike illegal to ride and void its warranty, it's also dangerous.

As Gavin Brough, manager of Gamma Transfer Division Shimano Service Center in Edinburgh, told TechRadar in a recent interview, e-bike components tend to wear out faster than those of a conventional bike even under normal conditions. 

“This is due to the extra force the drive unit puts on the chain and cassette," he said. "Being a slightly heavier and potentially faster bike, you may also need to change your brake pads more often.”

Hacking your e-bike to increase its power output will exacerbate that process and put extra strain on its drive system, which could have disastrous results. There's also the risk of crashing with a pedestrian, motorist, or another cyclist, who won't expect an e-bike to move so quickly.

Not so fast...

Hacking an e-bike also has legal repercussions. In France, 'tuning' to exceed the 15.5mph limit is already an offence punishable by a fine of up to €30,000 or up to a year in jail, and if delimiting becomes a common practice, authorities around the world may feel they have no choice but to restrict the sale and use of all e-bikes.

That's not just bad news for riders, but also the e-bike industry as a whole.  As eBikeTips reports, the Confederation of the European Bicycle Industry (Conebi) has decided to take action, and published a statement committing to prevent tampering. Many of the biggest names in e-bikes have pledged their support, including Bosch, Raleigh, Shimano, Specialized, SRAM and Trek, to name just a handful.

Delimiting e-bikes is therefore likely to get much more difficult over the coming years – and it's simply not worth the risk. Even if you don't have an accident or get caught, you won't necessarily get better performance out of your bike. 

An e-bike's software is tuned for a top speed of 15.5mph, which means it may behave unpredictably after being tinkered with, and your bike's range will be cut dramatically. You won't see a big speed boost on hills either, as you'll still be limited by the 250W motor, and it'll make no difference at all on fast descents.

If you want more speed on the flat, investing in a good road bike and riding under your own steam is the way forward.

Cat Ellis

Cat (@CatEllisBristol) is the fitness and wellbeing editor at TechRadar. She's been a technology journalist for 11 years, and cut her teeth on magazines including PC Plus and PC Format before joining TechRadar. She's a trained run leader, and enjoys nothing more than lacing up her shoes and hitting the pavement. If you have a story about fitness trackers, treadmills, running shoes, e-bikes, or any other fitness tech, drop her a line.