I've ridden plenty of electric mountain bikes over the years and one thing has become increasingly clear: the rate at which motor technology is developing is extraordinary.Not long ago, 85Nm of torque and 600W of peak power were considered more than enough. Now, Avinox is offering up to 150Nm and 1,500W, while Bosch has responded with increasingly powerful software updates.Against this backdrop, I recently had the opportunity to test Shimano's new EP810 motor, fitted to Honda's RN0 electric mountain bike.With 100Nm of torque, 750W of peak power and a claimed weight of 2.3kg, Shimano's latest motor is already some way behind the leading competition on paper.Unfortunately, my experience on the trails suggested the gap could be even greater than the numbers imply.Power isn't everything Avinox's M2S motor delivers an immense amount of power. Scott Windsor / Our Media Having recently ridden the Avinox M2S, I wasn't expecting Shimano's latest offering to match its extraordinary power output. Frankly, I don't think it needs to.The M2S produces enough assistance to make even the steepest climbs feel manageable, but it's the precision with which that power is delivered that impresses me most.Bosch's latest Performance Line CX is similarly accomplished, with predictable assistance that enables you to negotiate technical terrain without constantly fighting the motor.The Shimano motor, however, felt a couple of generations behind. My biggest criticism was its sensitivity, or rather its lack of it.On relatively tame technical climbs, I found myself dragging the rear brake to control the motor's assistance, using it almost like a clutch to prevent the bike from surging forward.It's a technique I thought I'd largely left behind as motor technology improved.On both the Avinox and Bosch systems, I'd expect to negotiate the same obstacles by carefully adjusting pressure on the pedals.Crucially, it was only after I'd completed my testing that I was informed the motor fitted to the Honda was a pre-production unit.Until that point, I'd been riding and assessing it without being made aware of its development status.I was told changes could be made before production, although what those changes might involve, and whether they would address my criticisms, hasn't been confirmed.It's an important caveat, but it doesn't change the experience I had on the trails.And it left me questioning where Shimano fits into an increasingly competitive market.The competition isn't standing still Bosch's Performance Line CX motor can now deliver 120Nm of torque. Scott Windsor / Our Media Shimano's problem isn't simply that Avinox has raised the power ceiling.Bosch has demonstrated how much performance can be unlocked through software, with its latest Performance Line CX update increasing maximum torque to 120Nm.Meanwhile, Avinox has rapidly expanded its presence across the industry, with manufacturers increasingly adopting its motors.But perhaps the biggest threat to Shimano's position isn't another conventional mid-drive motor.At Eurobike this year, I saw emerging eCVT systems from Avinox and Gobao that could fundamentally change how electric mountain bikes are designed.By integrating a continuously variable transmission into the motor assembly, these systems promise to eliminate the conventional rear derailleur, enabling automatic, stepless gear changes.They could also reduce maintenance requirements, remove vulnerable drivetrain components and enable riders to concentrate on the trail rather than selecting gears.There are still plenty of unanswered questions surrounding efficiency, weight and durability, and the latest systems have yet to prove themselves on the trails. However, the direction of development is clear.Manufacturers are no longer competing solely on power and torque. They're increasingly looking at the entire drivetrain as a single integrated system.That's potentially concerning for Shimano, a company whose business is built around both motors and conventional bicycle drivetrains.Where does Shimano go from here? Early impressions of the EP810 on Honda's RN0 eMTB suggest Shimano may have some catching up to do. Honda Shimano, of course, still has plenty going for it. Its established relationships with bicycle manufacturers, extensive component range and experience developing electronic shifting systems put it in a strong position to respond.There's certainly room in the market for motors that prioritise reliability, efficiency and natural-feeling assistance over headline-grabbing power figures. However, those qualities need to be demonstrated on the trail.My initial experience of the EP810 suggests Shimano still has work to do, particularly when it comes to delivering the precise, intuitive assistance that riders are increasingly coming to expect.The production motor may address these concerns and I'll reserve my final judgement until I've ridden one.For now, though, I can't help feeling Shimano is chasing a moving target.While it works to refine its latest motor, competitors are already exploring what could come next.With the industry developing this quickly, simply catching up might no longer be enough.