Bike test: Corratec 8-speed Coaster

A bargain Bosch ebike has arrived in Australia courtesy of no-frills distributor Reid Cycles. Simon Vincett tests and reports.

Bosch motors are the centre-piece of the premium ebikes of today, so it’s exciting to see the first bargain ebike in Australia using this pedal-assist system. A price close to three grand might not immediately seem like a bargain, but similar ebikes are about one thousand dollars more on average, and the components of this bike compare well to them and stand up well to the riding expectations most people would have for this bike.

Corratec is a German brand with a solid reputation in Europe that makes a full range of bikes from time-trial road bikes, through downhill mountain bikes to city and trekking bikes. They produce ebikes in mountain bike, city bike and trekking bike formats. This 8-speed Coaster fits into the city bike category.

Notable features, apart from the Bosch Active Line motor, include hydraulic rim brakes (Magura HS11), a Shimano internally geared hub (Nexus 8-speed) and a 400 watt-hour Bosch Powerpack 400 battery. The bike also boasts a headlight powered by the battery (Axa Pico 30E), a quality rear luggage rack (Racktime Bosch e-bike carrier) including a wired-in rear light, quality SKS Chromoplastics mudguards and Continental tyres. Parts of this calibre are sure markers of a practical and reliable bike.

The frame comes in a traditional diamond or a step-through version and an adjustable stem (from Zzyzx) allows customisation between a very upright position and a more forward-leaning position, like riding a mountain bike.

The Bosch motor operates in pedal assist mode, meaning it comes in when you pedal. The strength of its assistance depends on what level you choose: Eco, Tour, Sport or Boost. You can switch between assistance levels as you go with a press of a button on the handlebars, so you can call on more assistance when you need it. The motor cuts out when you don’t pedal and immediately if you apply the brakes.

The different levels of assistance draw more or less from the battery, with Eco drawing the least and Boost the most. Lots of uphill riding or headwind also drain the battery by requiring more from the motor. The display on the handlebar continuously updates the range you have left in each assist mode. A full battery will take you up to 140km in Eco mode or 40km in Boost.

The battery is easily removed from the bike to be plugged into a charger that operates off 240v mains power. A full charge takes three and a half hours and partial charges don’t harm the battery. A display on the side of the battery tells you how much charge it has.

The bike is not without flaws though, with the major one being in the bike’s gearing, which is too low. The Nexus hub gear is designed to provide eight different speeds, with three low, one that is one-to-one with your pedalling and four that are high gears for travelling at high speed. The problem here is that the sprocket for the chain at the Bosch motor (with 18 teeth) is smaller than the sprocket at the hub gear (with 21 teeth). This provides something more like four low gears, one one-to-one and three high gears. The effect is that I often found top speed a bit frustratingly slow. It is a few kilometres per hour slower than other Bosch ebikes in Australia.

This can be fixed by changing the sprocket on the hub, which is an operation a competent home mechanic could complete successfully. Otherwise, it’s a simple operation for a bike mechanic.

Another complaint from me concerns the back-pedal brake, which is annoying and redundant. The annoyance is that you can’t pedal backwards to set the pedal before taking off. The redundance is that the Magura hydraulic rim V-brakes are very good—one of the highlights of this bike—so it seems silly to add another braking system. But that’s how they like it in Germany and at this price you can’t expect these bikes to be tailored to Australian tastes.

 

Frame 6061 aluminium in diamond or step-through

Fork RST Sofi Fork suspension

Gears Shimano Nexus 8-speed hub gear with Revo Shift twist-grip shifter

Brakes Magura HS11 rim brakes and back-pedal brake

Tyres Continental Touring Plus 700x42mm

Motor Bosch Active Line centre drive

Battery PowerPack 400

Sizes Sm, Med, L, plus XS in step-through

Weight  25.25kg

RRP $2,799

83%

Function 32/40

Quality 34/40

Appearance 7/10

Price 10/10

For more info and to buy www.reidcycles.com.au