Wisper 905SE Performance

[ElephantsGerald]

In response to some questions KeithHazel has been asking, I got around to fixing the speedo and took my Wisper out at lunch-time to see how fast I could make it go.

First off, the speedo seems to be accurate over distance (I've measured the route several times before in the car), so I assume the reported speeds are accurate too.

Secondly, I'm 40, weigh 13 stone, and I'm on the fit side of not particularly fit.

So, having found a more or less flat bit of road (not easy around Herefordshire), I tried out various things. Its not very scientific, but when pedalling I was going at what felt like a reasonable and sustainable cadence, whilst trying to ensure the motor was still joining in (on the basis of the noises it makes; I can't detect the cut-out point from the way the bike feels).

I got the following (highly objective ) results:

• Throttle only: 14 mph
• Throttle + unrestricted mode: 16.5mph
• Pedelec only: 16mph
• Pedelec + unrestricted mode: 16 mph
• Pedelec + unrestricted mode + throttle: 19.5mph

Its worth mentioning that I couldn't get unrestricted pedelec performance without twisting the throttle at the same time. Up until now I've been riding without touching the throttle, which explains why, previously, pushing the de-restrict button didn't seem to do anything.

Obviously pedelec + unrestricted + throttle would be illegal on the roads, but thats a risk some folk may be willing to take.

Finally, I tried going as fast as I could, and got up to 20.5 mph, but didn't feel like I could keep that up for very long.

I not sure ('cos theres no speedo attached), but once past the point of motor assistance I think I could go faster for longer on my bog standard £100 15-speed Raleigh push-bike (mainly because its a lighter bike with a wider range of gears).

Keith and others, I hope this helps.

Regards,

Elephants

 

[keithhazel]

i heard a wisper

In response to some questions KeithHazel

Keith and others, I hope this helps.
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yes very much appreciated...i think most people on a flat road with no hills or wind also feel they can do more on a normal bike but we have the e-bikes for non perfect roads and weather, a nice back up..and for those of you with hills a brilliant plan b....unless im told otherwise i think a wisper may be of no use for my plans as want to pedal assist at 20mph constant..up to now its agatta that i have been pointed to for that.............or i buy a lightweight folding no e-bike that i can walk on and off buses with and use for inbetween journey routes....gotta think fast as the right weather is here for riding too...is the cost worth the better health i have to weigh up...i could plod around here on my quando getting fit but im not getting from a-b then.where riding the 42 miles i would get where i wanted and fitter too..apart from the first half dozen times when i might not notice im there as would be fast asleep on the sofa......mmmmm ..winning lottery ticket time i think...lol..

 

[Carol]

Just reading this post, can you tell me if there is a legal speed limit for electric or assist bike's in the UK, just out of curiosity would like to know the legal position. thanks Carol.

 

[Larkspur]

Just reading this post, can you tell me if there is a legal speed limit for electric or assist bike's in the UK, just out of curiosity would like to know the legal position. thanks Carol.

Hi Carol,

The maximum legal assisted speed for an electric bike in the UK is 15.5 mph: once the bike reaches that speed the power cuts off. Of course it is perfectly legal to go faster than 15.5 mph on an electric bike - provided you are not getting any help from the motor to do it.

Chris

 

[flecc]

Quite a few bikes only have a natural form of restriction Carol. By that I mean that the hub motor is internally geared to achieve the 15.5 mph on the voltage of the battery. Since that reduces as the charge goes down, it means the top speed reduces likewise. Some achieve the maximum on a fully charged battery and then gradually goe down to about a 14 mph maximum. Others like my main bike are faster to around 17 mph or a bit over on a freshly charged battery and gradually drop to the legal limit.

I doubt the law will ever be rigidly enforced on this, near enough is probably good enough for the authorities.
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