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I'll strap the Dyson to the pannier as a provocation 31st Dec...At least after 1st Jan, they won't be checking to see if your vacuum cleaner is over 1kw.
I'll strap the Dyson to the pannier as a provocation 31st Dec...At least after 1st Jan, they won't be checking to see if your vacuum cleaner is over 1kw.
Not true:Motor vehicles kill a jumbo jet load of people every month in the UK.
Quite likely to be true:How many people are killed by e-bikes? Almost nil per year.
Not true:
- road traffic deaths per month in 2019 is 146 (1752 / 12 months)
- a jumbo jet (or equivalent) carries 300-500 people
You're over-estimating by 270%.
Quite likely to be true:
- 4 pedestrians were killed by a cyclist in 2019
- 1 cyclist was killed by another cyclist in 2019
No details of whether any of these were ebikes, but it's statistically unlikely since ebikes sales and usage is going to be < 10% of normal bikes.
Sources:
Reported road casualties Great Britain, annual report: 2019
Personal injury accident statistics on public roads in Great Britain for 2019.www.gov.uk
https://www.gov.uk/government/statistical-data-sets/ras40-reported-accidents-vehicles-and-casualties
(the RAS40004 PDF)
How Many Seats Are There in a Standard 747 Jumbo Jet?
Modern 747 model aircraft, nicknamed "jumbo jets," can seat between 300 and 500 people. The exact number of seats depends on the type of 747 jet and the individual airline's configuration of the plane.www.reference.com
With Covid a jumbo jet probably classifies as 'full' with 1/3 that number, making the estimate pretty much right for 2020??Not true:
- road traffic deaths per month in 2019 is 146 (1752 / 12 months)
- a jumbo jet (or equivalent) carries 300-500 people
You're over-estimating by 270%.
I was made aware that this happened three days earlier. Since that was in private correspondence I can't add any detail, but I'm satisfied it did happen. It's commensurate with at least two previous actions by the force involved.no onwer has been named and there is a dearth of reporting on this case in the press, so until some evidence that it happened as reported, or even happened at all, I shall give it a healthy dose of scepticism.
It's absolutely true. I was personally involved. The guy's name is Adam B. This is his email to me after I sent him the letter, which he gave to the police. All previous comms were by phone.I do have issue with unqualified police personnel carrying out non home office approved testing methods to determine if an ebike is legal. Having said that, no onwer has been named and there is a dearth of reporting on this case in the press, so until some evidence that it happened as reported, or even happened at all, I shall give it a healthy dose of scepticism.
Wow! I've stowed that way in a special "In case my bike is impounded" folder. You'll be the first person I consult in that event! If it happened a lot and you charged a fee, you'd make a fortune writing letters.It's absolutely true. I was personally involved. The guy's name is Adam B. This is his email to me after I sent him the letter, which he gave to the police. All previous comms were by phone.
Hi Dave,
Thank you for the information it's very useful.
Good news that the police released our bike.
Many thanks for your help.
This was the letter I sent to Adam, which might be some use to anybody else that finds themselves in the same predicament:
Adam,
Here's some points that will help your lawyer:
1. From your description of what the police did (using a clamp-type current meter), they have used an invalid measuring method for the motor output power.
They have measured the power coming out of the battery, which has no direct relation to the power coming out of the motor.
The power coming out of the battery goes into the motor controller, which converts it into pulsed electrical power that it sends on to the motor. There is a conversion efficiency that has not been determined, but it's certain that less power will come out of the controller than what goes into it. You should ask the police, which numeric value they used for the controller's conversion efficiency.
The mechanical power coming out of the motor has no direct relation to the power going in because again there is a conversion efficiency, but in this case, the value would vary between 0% when the motor is stalled to something like 75% when running in optimum conditions. The main factor that affects the motor's efficiency is its rotation speed. At low speed, it's extremely inefficient (say 25%) and at normal running speed, it would be about 70%. Again you should ask what the conversion factor the police used and at the speed that the motor was turning when they measured it. This has to be the actual motor speed, not the wheel speed.
The motor will take the most current from the battery when it's running at its lowest speed when it's least efficient. As the motor speed increases,the current decreases because the motor generates a back electro-motive force (voltage) in proportion to its speed, which effectively reduces the battery battery voltage and, as current is proportional to voltage, the current goes down and so does the power as the motor speeds up.
In other words, it's virtually impossible to give a figure for output power based on measurement of the current coming from the battery, even if you knew the motor's speed at the time of measurement.You would have to plot it on a graph of the actual motor's efficiency - if you had one.
The only way to measure a motor's output power is to put the vehicle on a dynamometer - normally a rolling road type.
2. The police used an incorrect standard for what's allowed in a pedelec type vehicle. The government's website along with many other guides are incorrect, in that they state that the maximum output power is 250w. That's not UK law.
The UK pedelec regulations were harmonised with the European standard EN15194. The date that happened is very complicated. Some argue that it was effective from 2009, when the directive was made, but I think it was finally done in 2015. Either way, it's effective now. In EN15194 latest version (2017), the wording is "electrically power assisted bicycles of a type which have a maximum continuous rated power of 0.25 kW.
There are two key words in that statement. Firstly, it's the "rated" continuous maximum power. The vehicle' rating is done by the manufacturer. There is no regulation, nor standard for how a motor should be rated and the rating is independent of peak output power. EN 15194 refers to a test for motor rating, but that test is to insure that the motor isn't overrated. It's basically a pass of fail on whether the motor overheats.
The second key word is "continuous", which is different to peak power. The police measured peak power.That word was included in the standard because manufacturers allow the motors to run above their rated powers at low speed, otherwise you wouldn't be able to get the rated power at normal running speed.The Police didn't measure the continuous power, and I can't see any way continuous power could be measured.
In summary, my interpretation of EN15194 is that as long as the manufacturer rates the motor at 250w or less, then the vehicle is legal regardless of how much power the motor actually outputs.
From my experience, you'll struggle to find any EN15194 certified ebike on the road, where you wouldn't be able to measure at least 500W from the battery. Most are in the range 540W to 760W. That includes the systems from Bosch, Shimano, Yamaha, Brose, etc.
I hope this is of some use for you. Sorry if some of it is a bit technical. I tried to write it in layman's terms as far as possible.
Regards
Dave
All my services are free.Wow! I've stowed that way in a special "In case my bike is impounded" folder. You'll be the first person I consult in that event! If it happened a lot and you charged a fee, you'd make a fortune writing letters.