Suspension Fork KKE — Dual-Crown Air Fork for High-Power E-Bike Builds

Why a Dual Crown Belongs on a High-Power Conversion

A single-crown fork clamps the steerer once, at the head tube. A dual crown clamps the stanchions twice — above and below the head tube — which turns the whole front end into a far more rigid structure. On a conversion running serious power, that stiffness is the difference between a front end that tracks where you point it and one that flexes and wanders under braking.

This is the same layout used on downhill bikes and light electric motorbikes, and it exists for the same reason: weight and speed. A bike carrying a hub motor and a large battery is significantly heavier than the bicycle it started as, and it holds higher speeds for longer. The front end takes the consequences of both.

The trade-off is honest: a dual crown restricts steering lock and adds weight, and it requires a frame with enough head tube clearance for the lower crown to swing. It is not the right fork for a lightweight commuter conversion. It is the right fork for a high-power build that has outgrown its original chassis.

Air Spring and Preload

The fork runs an air spring rather than a steel coil, adjusted through the Schrader valve at the lower leg. That matters on a converted bike because rider weight plus motor plus battery varies enormously between builds — an air spring lets you tune spring rate to the actual weight of your bike rather than accepting whatever a fixed coil was wound for.

Set the pressure so the fork settles a sensible amount into its travel with you sat on the bike in riding kit, then use the preload adjuster on the top crown to fine-tune the initial part of the stroke. Start softer than you think and work up; a fork run too hard skips over the small bumps that actually cost you grip.

Fitting Points and Compatibility

The steerer is supplied long, with a usable range of 110–200mm, and is cut down to match your head tube and stem stack during fitting. Cut it once and cut it right — a steerer trimmed too short cannot be recovered.

Braking is disc only; there are no rim brake mounts and nothing to bolt a caliper to on the arch. The lower crown carries mounting points for a headlight and a mudguard, which is a genuinely useful detail on a fast converted bike that gets ridden after dark.

Before ordering, check three things on your own bike: that the head tube will accept the steerer diameter, that there is room for the lower crown to rotate without striking the frame or down tube, and that your front hub is built for a 20mm axle at 110mm spacing. If you’re unsure on any of them, send us a photo of the front of your bike and we’ll tell you.

How It Compares to Our Other Forks

This is the stiffest and most heavy-duty fork we stock. The NANLIO dual-crown fork is the closest alternative and uses a 110 × 15mm thru-axle instead, which makes it compatible with our MTX thru-axle wheel — worth considering if you want a dual crown without rebuilding a hub. For cross-country and light trail riding on a more modest build, the single-crown Bolany fork is the sensible, far lighter choice.

For the rest of the range, see the bike parts category, and if you’re specifying a build from scratch, the conversion kits.

Warranty and Returns

Every Suspension Fork KKE purchased from All4eBikes is covered by a 12-month warranty against manufacturing defects, alongside a 30-day return window. Please note that a steerer cut to length cannot be returned.