I managed to get a chance to ride my Wisper into work last week. A combination of a business trip and flu having previously prevented me doing it for a couple of weeks.
I'll do a more detailed review when I've got to know it better, but my initial view is that there are some very good points about it and some less good points.
Good bits
1. Speed - It's fast. Normally cruise at 17-19 mph and often get above 20. I got to work in 47 mins - compared to 51 on Powabyke and 54 on Powacycle and 56 on my unpowered bike. I expect that time might improve as I still had a bit of flu, caught a few red lights and am still getting the hang of the Wisper. Distance is 12.5 miles so, assuming 5 mins lost at red lights, average speed =17.9 mph.
2. Range from the new 13Ah battery - I did about 28 miles (detour on the way home) unrestricted with very liberal use of the throttle, and the battery had plenty of charge left. I've done a few more miles since and its still not ready to charge (I'm conditioning it). I expect it will be good for 40 miles. Obviously this range will decline with age, but I'm pleased with this sort of performance, especially given the cold weather, which has really reduced the range of my Powacycle NiMH batteries.
3. Brakes - I'd not had experience with disc brakes on bikes before, but the one on the Wisper is great. I can't remember a better brake on any bike.
4. Ride - It's not a bad bike to ride. Slightly harsh, which I guess is the aluminium, but it feels light and agile, steers well and is rideable with no power. With the forks locked it feels pretty rigid and solid. Feels well balanced with the rear motor.
Not so good.
1. Controls - three buttons control the mode (pedelec/e-bike/derestricted) which gives 9 combinations. It's not clear if a button is on or off and they are easy to flick by accident when changing gear or using the bell. Much of the time riding the bike is spent trying to work out which mode it is in and whether I have accidentally changed mode (hence potential for speed to increase!)
2. Controller operation. Simply, the bike delivers more power than needed initially but, after a short time under load, the controller reins it back in. It means the bike is not very satisfactory as a pedelec only, and I can understand why the Germans didn't want to sell it. It works much better as an e-bike with throttle (subject to 1 above).
3. Battery difficult to remove. Can't be removed at all without taking the seat out.
4. Quality of some components poor. In particular, rear brake (I had to replace it before using), seat (awful 'sofa' type, women's shape, completely out of keeping with the style of the bike) and speedo/battery indicator (basically its useless as a speedo (unreadable and gives incorrect readings - if you could read it!) and as a battery indicator (voltage based so shows full until empty) but has some use as an indicator of battery load (showing if the battery is under too much pressure, which helps you to work out when you are in de-restricted mode)).
5. Gearing. Mine is fitted with the 14-34 7-speed megarange, not the 11-34 mentioned in the spec on this site. the 14-34 gives just about enough top range but requires a higher cadence than many riders will be comfortable with. The 11-34 would be a better choice to take advantage of the big chainwheel.
I've not tried it on a significant hill yet. It copes very easily with short, steepish ones. It managed ok with a longer, moderate one (Holland Park Avenue), but needed use of throttle.
Frank