Powacycle Salisbury - 180 or 200W ?

[chazpope]

Hi

does anyone know how you tell which is which please ?

thanks

 

[flecc]

Hi Chaz

I saw your query in the clinic but left that for Powacycle as it's a private response area.

There may not be a 180 watt, since when a similar query cropped up about the 180 watt brush motor, Carl of Powacycle gave this reply:

"The Windsor (and Salisbury - both the same running gear) does have a BRUSHLESS motor. It's a mistake on the site, which has now been amended "

In other words, there was no 180 watt in those models at that time. That reply was on the 9th January 2007. No doubt Carl will give further information in due course in the clinic.
.

 

[chazpope]

brushless or not does not matter

I am asking specifically about the power rating - which has been advertised as both 180 and 200W

hope it gets answered soon

thanks

 

[flecc]

The 180 was shown as brushed in the site page, the 200 as brushless, hence my reply that in Carl saying the brushed should not have been shown, this also meant there was no 180 in those models.

 

[chazpope]

I still don't understand see the link between the 'brush' and the power issue - it was 180W on the website for a long time and it was also quoted by dealers as 180W until recently after which it became 200W - so maybe it was real and not just a website error.

Come on, Powacycle - clear the mystery !

 

[flecc]

Carl has confirmed in the Clinic that all the Salisbury models are 200 watt.
.

 

[Dick Lai]

Rated power

I think 180W is the rated power, sometimes it can reach 200watts. so..arise that situation.

 

[flecc]

No, it was a mistake as I indicated above Dick. The 180 was also shown as a brush motor, a type that had never been used on the Powacycle Salisbury, which had only ever had a 200 watt brushless motor.

These 180, 200 and 250 watt numbers are just legal classifications. All reach considerably higher actual outputs, varying from nearly 300 to 700 watts in current bikes from various manufacturers.
.

 

[Wisper Bikes]

Hi Dick

Hi Dick and welcome to Pedelecs!

Hi Flecc

I am STILL not sure what is meant by rated and maximum power and what exactly the law demands, surely if it is asks fr a motor with a maximum power of 250w then how can we supply a motor that had a maximum output so much higher and stay legal?

Please, please try to explain this one to me!!!!

Regards David

 

[Jed]

we need an electric bike university where all this stuff can be explained for those of us who struggle to understand what half is said in these forums

thanks
Jed

 

[flecc]

Hello David

The power output needs to average the legal figure across the range of operating speeds, 0 to 15 mph for example.

Most of these motors start with very low output as they start to turn, the power then rises to a peak that corresponds to around 8 mph on a 15 mph top speed bike. Thereafter the motor gradually becomes more and more efficient up to it's top speed, making ever better use of the supplied current.

As long as the mean of the powers at all points matches the legal figure, it's ok.

That's why a motor can be designed to have a huge output at certain speeds. For example, the Powabyke motor has a power curve thats the shape of a mountain peak, rising to 700 watts at about 7 mph and then falling away again. If you took say twenty equally spaced notional points along the speed versus power graph, measured the powers at each and then averaged the numbers, it should come out at 200/250 watts.

I think the legislators also have in mind that the power averages the legal figure over time while running, but clearly that is impossible to ascertain given the variations possible.

EDIT: See further post below on this aspect.
.

 

[coops]

@Jed: Yes I think there is a place, maybe on this forum, for a guide for those who want to get to grips with the mechanics of bikes, motors, batteries etc. in order to understand better how to get what they want/need from a bike.

Many, even most, will ask for advice and thats that, but for those who want to get more such a guide would be most useful. I've gained much insight from this forum into both bikes and ebikes in quite a short time on a steep learning curve, so I know it can be done; I've often thought that the information scattered around in the many threads could be centralized somehow.

I know too, though, that there are arguments against this though, like some will be put off asking questions, or leave bewildered etc: I'm not one to advocate innovation when its unnecessary, but since the still nascent ebike industry sometimes requires a hands-on DIY element, maybe a subforum for technical aspects would solve that problem, leaving the main electric bicycles forum here for Q & A type threads for advice on buying etc?

It would also be interesting to see how the amount of usage of the forums compares .

EDIT: Of course, division isn't necessarily useful (keeping up with multiple forum thread indexes for one!) and all could be (and probably would be! ) dealt with within the existing forum, in an "open" format...

Just my thoughts .

Stuart.

 

[flecc]

Hi Flecc

I am STILL not sure what is meant by rated and maximum power and what exactly the law demands, surely if it is asks fr a motor with a maximum power of 250w then how can we supply a motor that had a maximum output so much higher and stay legal?

Please, please try to explain this one to me!!!!

Regards David

Further to my above post on the motor side of power outputs, here's the situation over time that fit's legislators requirements for a 15 mph bike, using a notional journey.

Setting off, power output applied to the road starts at zero and rises if needed to a peak at about 8 mph, and this peak could be at well over the legal figure. When the bike reaches it's cruising speed on the flat of 15 mph, only about 100 watts is used to maintain that, and that could be at least halved if the rider pedals to help. When a hill is met and the speed drops, the power delivered rises, up to the maximum for the motor at about 8 mph, which could be 500 watts or more. If a steep hill causes speed to drop still more, the motor will start to waste wattage, but that doesn't count since it's not power delivered to the road, which actually starts to fall again. Then downhill the other side the motor isn't using anything, and eventually on the flat we are back to 50 to 100 watts being used.

You can see that the average power used over the journey could easily be only 200 watts even for a 500 watt motor, the measurement of which is determined on the basis of the current used related to the period of use. It's our old friend watt/hours again.

Hope this is some help David.
.

 

[Wisper Bikes]

Thanks Flecc

Thanks Flecc and congratulations on over 2000 posts, what do we call you now? Hare Krishna?

 

[flecc]

I didn't even know I'd gone over 2000 David, never had time to look, too busy posting.
.

 

[coops]

I was trying to catch your 2000th post, but missed it by 3 it didn't seem to have quite the same value by then and been busy posting too since . Congratulations though flecc .

Stuart.

EDIT: Yay! 2100th post! :-D @ 10.05pm June 19th 2007:

 

[flecc]

Thanks Stuart.