E-bikes are big in Europe, but unknown in the UK. Can Scott’s E-Spark change that? Well, if there was ever a bike aptly named for the addition of an electric motor, it’s Scott’s Spark.
But Scott has plenty of other frames with less auspicious names; was the Spark even the right platform to use?
Frame and equipment: a weighty issue?
This E version of the proven Spark chassis keeps its head tube and shock mounting top tube, as well as the very neat 3D linkage section that wraps around the seat tube. It also keeps the unique three-mode Fox Nude shock (full open, two-thirds travel and fully locked) with handlebar remote, and the flip chip for dropping the bottom bracket and slackening the head and seat angles.
The build is broadly equivalent to the conventionally-propelled £2,500 Spark 740, with a through-axle Fox fork (synced via a shared remote to the rear shock), Shimano drive gear with XT highlights, and Syncros figuring big for the cockpit, rims and saddle.
The Bosch power unit features a 400w battery
The big difference is the massive plastic case for the Bosch Performance motor, bolted below the curved plate that replaces the bottom part of the downtube and conventional bottom bracket area. The 2.42kg battery locks (with a proper key) neatly into place where you’d normally have a water bottle.
Slim, curved FSA Metropolis town bike cranks drive a tiny 16-tooth sprocket, while a trailing main pivot means the whole back end is stretched and the wheelbase elongated by almost 60mm. With the battery it’s 16.8lb (7.6kg) heavier than the 740.
Yes, you read that right. It’s 44lb all-up. But toggle the big Intuvia headunit display into 'turbo' or even 'sport' mode and weight just isn’t a problem.
Ride and handling: fully-charged fun
The problem is not ploughing straight off the trail, as even slight pedal pressure triggers the motor, launching you forwards like a spooked horse. Getting the long wheelbase round tight corners, and the simple fact you’re not expecting to arrive at uphill corners at downhill speeds, make the first few minutes on the E-Spark a startling experience.
It doesn’t take long to learn when to back off and how to nudge the pedals to feed the power in smoothly though, and soon we were power sliding the Scott up and down loose loamy turns in showers of peat and leaves.
The fact that only laughing like a maniac is making you breathless even on the steepest climbs has a profound effect on your riding. You start deliberately hunting out the slopes that have laughed at you for years, or ride down stuff just so you can ride back up it.
There’s minimal lag between our inputs and the motor kicking in
The Bosch motor is really impressive, with minimal lag between your pedal pressure and the power assist kicking in. It does drop torque slightly after a few seconds of initial surge in turbo mode, but you soon learn to expect that in the same way you learn to take straight-through lines up climbs rather than trying to weave the stretched E-Spark around obstacles.
The rearward main pivot means significant pedal bob in lower power settings, so we were glad of the shorter, tighter feel of the traction mode on less hectic climbs and used the lockout a lot on smooth trials. With the suspension locked out and a lower power setting, flex from the skinny cranks is obvious.
The unpowered descending of the Scott is better than you might expect. Apart from the head unit, all the battery and motor weight is kept as low as possible. Even with the long chainstays, the ratio of unsprung weight (wheels, rear mech, stays and lower fork) to sprung weight (rest of the frame, motor, kit and so on) makes the suspension feel more active and the bike more planted than normal.
That’s a definite bonus given the normally rather notchy feel of Fox’s Evolution dampers, and an extra-special bonus given the even notchier feel of these unique three-mode versions. The long tail also balances the battery weight so the bike’s in-flight balance is okay too, although the sheer weight means heaving it into the air more than a few times is bloody hard work.
Triple compound tyres give a reasonable grip/speed balance
Unsurprisingly, the long wheelbase, low-slung mass and slack angles make it very stable in a straight line and when braking heavily. The triple-compound Schwalbe tyres give a reasonable grip/speed balance too.
Turning the E-Spark takes a lot more effort than usual, particularly with only 700mm bars to crowbar it into corners. We also dropped the chain off the small motor sprocket several times during testing. Obviously you’re not going to be able to fit conventional chain devices to keep it secure.
The more we rode the E-Spark, the more we wondered why the company hasn’t motorised one of its longer-travel Genius bikes instead. The extra weight would be tiny compared to the motor mass, more suspension would mean the chain gets bounced less, and you’d have wider bars and a shorter stem to coax it through corners. Maybe E-Genius just doesn’t sound as good!
You must keep a very close eye on battery life. While the pack starts off with a nominal 60km of juice, estimates of remaining range can shrink to less than half that after only 10km of high-power riding. With only a 16-tooth cog and skinny cranks to propel 45lb, the thought of running out of charge a long way from home is a serious worry.
Keep a close eye on battery life – if it goes flat, it’ll take your will to live with it
The way the Bosch motor works in tune with pedalling, and the potentially massive difference it makes to speed left us really impressed with the E-Spark. It behaves better than we expected on descents too, although the suspension is still relatively limited and the chain prone to dropping.
This article was originally published in What Mountain Bike magazine, available on Apple Newsstand and Zinio.
via BikeRadar.com http://ift.tt/1fvtfVb
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