Iis it seemingly non-stop rain in the UK? Bad design? Or maybe the way they are ridden or cleaned? Why do so many e-bike owners complain about having to replace their motors so often?
Some owners of mountain bikes with fourth-generation Bosch electric motors describe having four or five—yes five—replacement motors installed during the two-year warranty period. Owners of other brands say theirs only lasted 800 to 1,000 miles.
The problem seems to mainly affect all-weather mountain bikers, particularly in Wales and other wettest areas of the UK, as they are not properly sealed against water ingress.
This week one of the UK’s leading independent ebike motor specialists, Fordingbridge, Hampshire-based eBike Motor Center, told Guardian Money that around 250 motors a month – of all types – are being sent in from owners desperate for a cost-effective solution. to problems including faulty bearings, faulty torque sensors and water damage to printed circuit boards.
With manufacturers asking up to £700 for an out-of-warranty replacement motor, it’s no wonder some of those affected say they’re going back to a conventional bike.
Keen ebike rider Andy Fenwick, who lives in Wiltshire, contacted Guardian Money to ask if we were aware that so many bikes had failing motors.
A 71-year-old £5,000 Cube motorcycle with a fourth-generation Bosch electric motor stopped working out of warranty.
Although it was resurrected by a software update and didn’t require a replacement, he says after browsing various bike forums he was amazed at the number of motors that needed to be replaced. He says the problem is compounded by the fact that these units cannot be repaired – parts are not available from Bosch. Some owners say that Bosch told them not to ride them in the wet, which is patently absurd.
“E-bikes are great for the rider and should be great for the environment, but it seems to me that a lot of motors are not fit for purpose,” he says.
“I’ve seen several reports of riders having three to five trades in two years. It seems to suffer from error codes after minor shocks or being too close to a magnetic source.
“Riders’ bikes stopped working after they simply leaned the bike against a lamppost or ran over it [magnetic] traffic light sensor grid on the road.
“The big problem is water. The latest units don’t seem to be able to withstand the British weather. Every time one fails, they have to replace the entire unit and the old one ends up in the landfill. How can that be a good thing? We need better right-to-repair legislation in this area.”
Fenwick wrote to Bosch to improve the design and make parts available so the engines could be repaired, but received no reply.
Bosch says: “Reliability and quality are of the utmost importance and the power units are designed for many years of service. Still, problems can arise with any technical product. We work closely with vendors and customers to find fast, customer-oriented solutions.”
He says some of the first-generation engines had problems caused by water, but later models were improved with improved seals and bearings. “The latest units are IP54 dust and splash proof and most error codes caused by magnetic interference disappear after a reboot.
“In the event of a major failure, the engine will be collected for further analysis and Bosch will decide on a case-by-case basis whether it can be subjected to the remanufacturing process. The customer gets the power unit back in fully functional condition after the ‘end’ test,” he says.
If a bike fails outside of warranty – usually two years for the motor – and the owner refuses the manufacturer’s help, they face a fight with the shop or a search for a cheaper repair.
The Consumer Rights Act gives buyers some indemnification against the seller for up to six years after purchase, although this can be difficult to obtain as some shops will claim that the owner has misused the bike.
A quicker and cheaper option may be to send the motor to an eBike Motor Center, who charge between £250 and £370 for a complete overhaul of most motors, and significantly less for minor repairs such as replacing bearings, sensors, circuit boards and other internal components that Bosch does not provide Customers seem to be happy with the service.
In the meantime, the advice for ebikers seems to be to keep your bike as dry as you can – often easier said than done – and be very careful when washing it, certainly not engine washing. And if you have a Bosch 4 motor, stay away from magnets.