Witter ZX504 Cycle Carrier review

Ultimate carrier for you and MAMIL mates?

Our rating 
4.0 out of 5 star rating 4.0
GBP £600.00 RRP
Witter's ZX504 Cycle Carrier doesn't come cheap but then, quite possibly, neither did your bike

Our review

A premium carrier, for your premium bikes, on your premium car
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British brand Witter’s stock-in-trade is making and fitting towbars, so it’s no surprise it’s built a name as a maker of towbar-mounted cycle carriers. Its new ZX500 range is its most advanced, and premium, yet with a choice of three platforms – carrying two, three or four bikes.

  • Highs: Sturdy, secure, reasonably easy to use
  • Lows: Some patience required, heavy to lift

You’ll need a towball, and if you don’t have one this will cost between £250-500 to buy and fit, including the electrics, which can make this kind of carrier seem costly. That said, towball-mounted carriers have advantages over hatch and roof-mounted racks – carrying bikes behind your car is better for your fuel economy, putting bikes on the rear is easier than onto the roof and a number of cars with rear spoilers can’t take a boot-mounted rack.

We tested the ZX504, as it seems perfect for the family MAMIL who takes mates to events. At 23kg, the Witter isn’t light but it does have wheels so you can roll it from garage to car before following the five-step setup, and it can carry up to 60kg.

Each step, and associated lever, is numbered and colour coded – green to mount, red to remove. Gird your loins, lift and drop onto the towball and it clicks into place. With the rack against the boot you can swivel it on the ball to straighten.

Once the platform is flat, it won’t move on the ball and can be locked in place with the supplied key. A separate U-shaped bar lifts to the vertical and attached to these are three different length bars, with ratchet fastenings that attach to the first three bike frames. A separate short bar secures bikes three and four to each other.

If you’re carrying four large road bikes you’ll need to do a bit of 3D puzzling – the bars securing bike to carrier can be moved around and we found that for large frames we had to attach them to the ‘down’ section on the carrier and down tubes on the bikes. The ratchet clamps to the bike are lockable and once locked can’t be removed at either end so your bikes are secure. For larger road bikes we found that removing and reversing the wheel cradles – there’s a securing screw underneath – worked best.

Once loaded and locked, the ZX504 felt very secure and our bikes didn’t move a great deal as we drove – perhaps not surprising as Witter’s designer Martin Dickinson explained that the carriers are tested around the Millbrook motoring proving ground… including sections of pavé! One excellent feature is that the carrier tilts with your bikes on board to allow access to the boot.


When empty of bikes, the carrier folds up against the boot but a glitch with our test carrier – from an early batch, since corrected – meant that the light board plate didn’t remain upright over bumps. That aside, the ZX504 has persuaded us that tow bars aren’t just for caravans!

Product Specifications


Name ZX504 Cycle Carrier (15)
Brand Witter

Load Capacity (kg) 60
Bike Capacity 4 Bikes
Car Rack Type Tow Bar Mounted