This doesn’t really come under the category of a ‘bike review’ – maybe a two-bike review! Anyway, my apology if it’s a bit too long (I had to split it into two posts because there’s a message length limit) and I hope the moderators will let me off – I promise not to do it again – for a while at least.
So – Part 1....
I’ve had a Wisper 905Se since New Year 2009, and it’s still in use – despite the fact that the battery is getting somewhat tired after all this time. I’d considered putting it onto Ebay but whoever bought it would need to buy a new battery so I doubt I’d get a good price for it.
Anyway, the point is I’ve been riding a Kalkhoff Sahel Pro since April (no, not the S model) and although I thought that would become my exclusive ‘ride’ I find I still use the Wisper, though not anywhere near as much.
I’ve more or less decided that I’ll get a new battery for the Wisper next year – and probably I’ll keep it. Both bikes have lots to commend them, and I thought I might share my observations on both and what I like (or not) about each of them.
The Kalkhoff is slower under power – it cuts out completely at around 16.5 MPH. There’s no way to fiddle it either – the speed is measured by a magnet on the rear wheel and a frame-mounted pickup. The system will assist you from rest just as soon as you apply some weight to the pedals – but the power is fed in sensibly as the speed builds up – so if you disconnected the pickup you wouldn’t get much help at all. Quite clever. The latest Panasonic system is a quantum leap ahead of what was being fitted three or four years ago. It’s 36 volts (at last) and you get a 14 amp hour battery – coincidentally, the same spec as the Wisper. However, that’s about as far as it goes if we’re talking about similarities. The ‘famous’ torque sensor is still a feature of the Panasonic drive, so you get assistance in direct relation to how much effort you put in. However, the level of assist available is now (up to) three to one if you select ‘high’ assist mode – which means you don’t need to pedal too hard to get lots of help.
The Wisper, being in effect four years older, is nowhere near as sophisticated. This is not a complaint – it was also less than half the price when I bought it. One shortcoming of the rear hub motor setup is that it’s just fine on the flat or downhill, but if you’re climbing anything much above a moderate incline you have to work damn hard to keep the speed up so the motor is not too far out of its ‘sweet spot’ of performance. The seven speed derailleur only applies to what effort you’re putting in to turning the pedals. In the case of the Kalkhoff not only your effort but also that of the motor go through the gears – in this case a nice eight speed Alfine hub gear. No matter how steep the climb, you can find a gear which makes both you and the motor happy, and you can get maximum power out of the motor under pretty well any circumstances. You may not realize that an ebike motor doesn’t deliver a lot of power until it’s running at some 70-80% of its rated top speed. You can certainly appreciate that fact if you allow the Wisper to drop below about 10-12 MPH on a hill, because the motor speed relates directly to the speed you’re travelling. On the Kalkhoff you just change down and if you’re pedalling comfortably the motor is comfortable too. It’s not just the principle of the thing which feels right – it hangs together beautifully. You have to approach it differently when it comes to changing gear though – you need to ‘feather’ the pedals to get the power off so that the gear change comes easily. It’s less forgiving than a derailleur to being shifted with the power on – and not forgetting that if I were being clumsy I could be hitting that hub gear with well over double the power a fit and much younger rider could produce. Of course you can change right through the box when stationary – I can’t do that on the Wisper and I find myself forgetting that with a derailleur you really need to be in the right gear to pull away before you come to a stop.
The Wisper affords two methods of motor control – a pedal sensor and a throttle. I’ve never been particularly happy with the pedal sensor system on the Wisper as it’s ‘all or nothing’. By that I mean that you do get a ‘low/high’ switch box on the left of the handlebar, and ‘low’ is probably about 20% power, with ‘high’ giving about 80% power. I leave mine on low all the time and use the throttle to regulate the amount of power in real time. The 20% assist setting gives very little help, but the 80% setting comes in with a bang after about one turn of the pedals – which can give rise to some tricky situations. The Kalkhoff doesn’t have a throttle control, but the pedal assist system is splendid – it does just what you expect and with almost no lag at all. You can pedal away from rest and get just as much assistance as you may need according to how hard you pedal.
I’m led to believe that current Wispers don’t give you the option of getting the motor to assist above about 16 MPH. Mine has that useful green button by the left handlebar grip – it’s a ‘push-on push-off’ switch and when it’s on you get assistance to somewhere near 20 MPH. Of course there’s a price to pay, in that if you rely on it too much and are a bit lazy, or unfit, your range takes a nose dive, but I’ve found it’s good for around 35-40 miles the way I ride, though I suspect by now 30 miles is about the limit because of the battery’s age and the fact that I’ve used it quite a bit.
So – Part 1....
I’ve had a Wisper 905Se since New Year 2009, and it’s still in use – despite the fact that the battery is getting somewhat tired after all this time. I’d considered putting it onto Ebay but whoever bought it would need to buy a new battery so I doubt I’d get a good price for it.
Anyway, the point is I’ve been riding a Kalkhoff Sahel Pro since April (no, not the S model) and although I thought that would become my exclusive ‘ride’ I find I still use the Wisper, though not anywhere near as much.
I’ve more or less decided that I’ll get a new battery for the Wisper next year – and probably I’ll keep it. Both bikes have lots to commend them, and I thought I might share my observations on both and what I like (or not) about each of them.
The Kalkhoff is slower under power – it cuts out completely at around 16.5 MPH. There’s no way to fiddle it either – the speed is measured by a magnet on the rear wheel and a frame-mounted pickup. The system will assist you from rest just as soon as you apply some weight to the pedals – but the power is fed in sensibly as the speed builds up – so if you disconnected the pickup you wouldn’t get much help at all. Quite clever. The latest Panasonic system is a quantum leap ahead of what was being fitted three or four years ago. It’s 36 volts (at last) and you get a 14 amp hour battery – coincidentally, the same spec as the Wisper. However, that’s about as far as it goes if we’re talking about similarities. The ‘famous’ torque sensor is still a feature of the Panasonic drive, so you get assistance in direct relation to how much effort you put in. However, the level of assist available is now (up to) three to one if you select ‘high’ assist mode – which means you don’t need to pedal too hard to get lots of help.
The Wisper, being in effect four years older, is nowhere near as sophisticated. This is not a complaint – it was also less than half the price when I bought it. One shortcoming of the rear hub motor setup is that it’s just fine on the flat or downhill, but if you’re climbing anything much above a moderate incline you have to work damn hard to keep the speed up so the motor is not too far out of its ‘sweet spot’ of performance. The seven speed derailleur only applies to what effort you’re putting in to turning the pedals. In the case of the Kalkhoff not only your effort but also that of the motor go through the gears – in this case a nice eight speed Alfine hub gear. No matter how steep the climb, you can find a gear which makes both you and the motor happy, and you can get maximum power out of the motor under pretty well any circumstances. You may not realize that an ebike motor doesn’t deliver a lot of power until it’s running at some 70-80% of its rated top speed. You can certainly appreciate that fact if you allow the Wisper to drop below about 10-12 MPH on a hill, because the motor speed relates directly to the speed you’re travelling. On the Kalkhoff you just change down and if you’re pedalling comfortably the motor is comfortable too. It’s not just the principle of the thing which feels right – it hangs together beautifully. You have to approach it differently when it comes to changing gear though – you need to ‘feather’ the pedals to get the power off so that the gear change comes easily. It’s less forgiving than a derailleur to being shifted with the power on – and not forgetting that if I were being clumsy I could be hitting that hub gear with well over double the power a fit and much younger rider could produce. Of course you can change right through the box when stationary – I can’t do that on the Wisper and I find myself forgetting that with a derailleur you really need to be in the right gear to pull away before you come to a stop.
The Wisper affords two methods of motor control – a pedal sensor and a throttle. I’ve never been particularly happy with the pedal sensor system on the Wisper as it’s ‘all or nothing’. By that I mean that you do get a ‘low/high’ switch box on the left of the handlebar, and ‘low’ is probably about 20% power, with ‘high’ giving about 80% power. I leave mine on low all the time and use the throttle to regulate the amount of power in real time. The 20% assist setting gives very little help, but the 80% setting comes in with a bang after about one turn of the pedals – which can give rise to some tricky situations. The Kalkhoff doesn’t have a throttle control, but the pedal assist system is splendid – it does just what you expect and with almost no lag at all. You can pedal away from rest and get just as much assistance as you may need according to how hard you pedal.
I’m led to believe that current Wispers don’t give you the option of getting the motor to assist above about 16 MPH. Mine has that useful green button by the left handlebar grip – it’s a ‘push-on push-off’ switch and when it’s on you get assistance to somewhere near 20 MPH. Of course there’s a price to pay, in that if you rely on it too much and are a bit lazy, or unfit, your range takes a nose dive, but I’ve found it’s good for around 35-40 miles the way I ride, though I suspect by now 30 miles is about the limit because of the battery’s age and the fact that I’ve used it quite a bit.
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