We picked the harder path on purpose

When electric bikes went heavy and integrated, we stayed with friction drive. It is the only way we know to add assistance without changing the bicycle — no new wheel, no drivetrain work, nothing you cannot undo in ten minutes.

Why the clutch is electronic, not mechanical

Friction drive has one hard trade-off. The roller has to press the tyre hard enough to grip, but contact while the motor is off would spoil the ride. The obvious fix is to lift the roller off the tyre whenever you stop using assistance, and that is what most friction kits ask you to do.

We think that is the wrong trade. In normal riding you almost never need the roller fully separated. Re-engaging it costs you a slower start, and every engage-and-release cycle wears both the tyre and the friction layer — the two parts you would rather not replace.

So we solved it electronically instead. The roller stays in light contact and the controller cancels its resistance, so there is no noticeable drag and assistance picks up the moment you ask for it. The mechanical knob is still there for when you genuinely want the roller clear of the tyre — a flat battery, a long unassisted ride — but you do not need it just to pedal home.

What we did not do

We did not chase a bigger peak-power number. Every figure we publish is continuous output — what the motor holds, not a two-second spike. On a friction drive, usable traction and stable output matter more than a headline watt figure.

The number we care about

First-generation QR-E motors are still running after six years. That is the result we build for.

Qiroll was built for the cyclist who likes their bicycle and wants to go a bit further on it. If you are not sure whether a QR-E fits your frame, send us a side photo of the rear wheel — we will tell you either way.