I am all for freedom of information.
Woosh supply you with a socket and an unplugged throttle with a notice that says woosh cannot plug it in but you can.
Bafang 8fun CD 36v or 48v ?
- Thread starter Rohloffboy
- Start date
Woosh supply you with a socket and an unplugged throttle with a notice that says woosh cannot plug it in but you can.
My reasoning for going for the 500w motor in de-tuned to 250w form, is in case UK ebike law, grows a pair.
In fact the UK, did move from 200w to 250w in anycase, so who knows what may happen in the future.
With Brexit comming fast, I feel that the UK ebike industry should be pushing for parity with the USA and not the EU, and shame on them if they don't, not to mention a provision for "S" Pedelecs like what they have in Germany etc.
In fact the UK, did move from 200w to 250w in anycase, so who knows what may happen in the future.
With Brexit comming fast, I feel that the UK ebike industry should be pushing for parity with the USA and not the EU, and shame on them if they don't, not to mention a provision for "S" Pedelecs like what they have in Germany etc.
I am no expert, but if a motor is capable of 500w and the maker or distributor can restrict it to 250w, then it becomes a 250w motor, the markings on the case, would just confirm that it is a 250w motor for region's were no more than 250w is permitted as legal.
I don't see it as an issue, unless the motor is re-tuned to be able to produce 500w.
In the same way as a 250w motor, can have it's speed restriction of 15.5mph changed to 30mph, which would then make it a none legal Pedelec.
So the same legal rules, must apply to power as well as speed.
I rest my case m'Lord!
I don't see it as an issue, unless the motor is re-tuned to be able to produce 500w.
In the same way as a 250w motor, can have it's speed restriction of 15.5mph changed to 30mph, which would then make it a none legal Pedelec.
So the same legal rules, must apply to power as well as speed.
I rest my case m'Lord!
The power test is if you run the motor at 250watts continually will it overheat and fail. If not it passes as a 250 watt minimum motor.
So manufacturers rate the motor as 250w then set the controller to give upto 700 watts peak!
The law is an ass, it says maximum of 250? The test is at least 250, the manufacturer sets peak power of ???
The dealers have pushed the peak ratings up and up.
So manufacturers rate the motor as 250w then set the controller to give upto 700 watts peak!
The law is an ass, it says maximum of 250? The test is at least 250, the manufacturer sets peak power of ???
The dealers have pushed the peak ratings up and up.
According to the UK gov website, the definition of EPAC is that it will provide 250w at the output of the motor and not provide motor assistance above 15.5m/hr. So they do not care whether your motor could generate kW of power ifit were supplied with larger voltages , just that the mechanical power output from the motor is constrained to 250w when the conditions for EPAC type approval were authorised. This is similar to the operational definitions of car engines in terms of horsepower on the basis of engine capacity. if a car enthusiast adjusts the camshaft settings, or uses nitro they can increase the power output considerably, but then the car has lost its type approval and becomes technically illegal.
As other posters have noted, nobody is going to care, unless there is an accident, and the victims solicitor pushes for compensation.
D
Deleted member 4366
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The law is that the motor should have a maximum continuous rating of 250w. There's no rule anywhere about it's power output. You can't use a motor rated at 500w and restrict its power. That guideline is only for laymen that don't understand standards or engineering matters.
You can't use logic. The law says that it has to be a 250w motor. You can't use a 500w one.
D
Deleted member 4366
Guest
The USA law is mainly 750w, but that's maximum output power, which is definitive and can be measured. Our 250w continuous rated power is not definitive because there's no basis for the rating. If you look at that guy's 200w rated Heinzmann kit that's in the classified section, you'll see that it has a 33 amp controller and 36v battery. That means a maximum of 1320W from the battery or around 1000w at the back wheel. It's legal in the UK but too much power for USA.
Thanks again d8veh for helping me see through the muddy waters of ebike law, as you have already mentioned, the law is an ass!
I understand that there has to be some kind of restriction on power, but 250w does seem woeful, the speed limit is more important in my mind, but there again as most fit cyclist can easily go along on a none electric bike at +20mph, the 15.5mph cut of just seems plain stupid to me.
If you wan't to use your ebike for commuting to work, mostly along Tarmac roads, then surely an "S" Pedelec would be the bike of choice, which would be arguably safer than using a 15.5mph restricted ebike.
When you see roadies on a cycle trail, they don't whizz along at 20+ mph, they just ride according to the conditions, like the rest of us on bikes, be they ebike or not.
It's just a pity that the law, does not account for people using common sense, although some would argue that is what the law is there for.
I understand that there has to be some kind of restriction on power, but 250w does seem woeful, the speed limit is more important in my mind, but there again as most fit cyclist can easily go along on a none electric bike at +20mph, the 15.5mph cut of just seems plain stupid to me.
If you wan't to use your ebike for commuting to work, mostly along Tarmac roads, then surely an "S" Pedelec would be the bike of choice, which would be arguably safer than using a 15.5mph restricted ebike.
When you see roadies on a cycle trail, they don't whizz along at 20+ mph, they just ride according to the conditions, like the rest of us on bikes, be they ebike or not.
It's just a pity that the law, does not account for people using common sense, although some would argue that is what the law is there for.
The law is actually very clear on this. The EU regulations 2002\24 and the updated uk government regulations advisory 2015 refer to power assistance of 250w. It is therefore the mechanical power available at the output of the motor. They refer also to it being continuous power in order to distinguish it from instantaneous power which might be available if inertia or other dynamic energy storage techniques were used. Because the parliamentary draftsmen are not engineers, does not mean they are silly or Ill informed. They do employ advice from experts and every word in these communications has been considered in depth. They know that these words will be tested in court.
It is noticeable that the newer regulations have removed a weight limitation and the number of wheels that a cycle may have.
The EU directive regulates a wide range of other mechanically propelled devices from those under human power, electric , internal combustion, mobility vehicles etc .
It exempts from much of the stringent regulation those powered devices which travel slower than 6km hr, cycles with continuous power below 250w provided that power assistance terminates at 25km hr . They provide also for less regulation on more powerful machines, below 1kw andbelow 4kw.
Of course the power output of a motor can be controlled.... That is the duty of the controller
Thanks for that Danidl.
And does that mean that I am correcting in thinking, that a Bafang 8fun CD motor that is factory set to 250w, even though it could be set to 350w or 500w for other regions would actually be legal in the UK, as it will only perform as a 250w motor in anycase.
From a manufacturers point of view, this does make sense, as you have the one motor, that can be configured to 250w, 350w or 500w depending on the market that it is intended for.
The fact that the motor case is stamped 250w, is neither here nor there as the motor will simply perform the output power as set up from the factory or distributor.
And does that mean that I am correcting in thinking, that a Bafang 8fun CD motor that is factory set to 250w, even though it could be set to 350w or 500w for other regions would actually be legal in the UK, as it will only perform as a 250w motor in anycase.
From a manufacturers point of view, this does make sense, as you have the one motor, that can be configured to 250w, 350w or 500w depending on the market that it is intended for.
The fact that the motor case is stamped 250w, is neither here nor there as the motor will simply perform the output power as set up from the factory or distributor.
We need an executive summary, these questions and confusions keep coming around:
- If it is stamped 250 W it is a 250 W motor
- the controller max Amps times the battery max voltage (A x V = W) gives the peak Watts your 250 W motor is capable of (ex. my GSM external controller motor - 15.19 A x 41.5 V = 630.38 W)
- the power at the wheel will be less because of losses
Next we need a section on torque - fast spinning motors (at the drive shaft) provide less torque than slow spinning ones. Other factors influencing torque are motor internal gear ratio and bike wheel diameter. Forum experts are here to provide information on which motor is best suited for hill climbing vs top speed.
Which brings us to top speed capability of various motors - most common 250 W hub motors using standard controllers and a 36 V battery have a top speed with no pedaling on flat ground of around 32-33 km/h (20 mph), verified by personal experience. Mid-drive motor speed will depend on the gear you are in in the same conditions, I have seen 40+ km/h on the flat with my GSM in 6th gear, 7th gear (46:11) giving no increase in top speed I assume that 40-42 km/h is tops for that motor/controller combination. With a little bit of pedalling in 7th gear however 45 km/h is easy to attain. Both tests were done with the motor unrestricted of the 25 km/h limit setting of the controller/LCD.
If you need more power - speed - torque from a legal on road use vehicle than the above then get an electric moped, there are some very nice models on the market.
- If it is stamped 250 W it is a 250 W motor
- the controller max Amps times the battery max voltage (A x V = W) gives the peak Watts your 250 W motor is capable of (ex. my GSM external controller motor - 15.19 A x 41.5 V = 630.38 W)
- the power at the wheel will be less because of losses
Next we need a section on torque - fast spinning motors (at the drive shaft) provide less torque than slow spinning ones. Other factors influencing torque are motor internal gear ratio and bike wheel diameter. Forum experts are here to provide information on which motor is best suited for hill climbing vs top speed.
Which brings us to top speed capability of various motors - most common 250 W hub motors using standard controllers and a 36 V battery have a top speed with no pedaling on flat ground of around 32-33 km/h (20 mph), verified by personal experience. Mid-drive motor speed will depend on the gear you are in in the same conditions, I have seen 40+ km/h on the flat with my GSM in 6th gear, 7th gear (46:11) giving no increase in top speed I assume that 40-42 km/h is tops for that motor/controller combination. With a little bit of pedalling in 7th gear however 45 km/h is easy to attain. Both tests were done with the motor unrestricted of the 25 km/h limit setting of the controller/LCD.
If you need more power - speed - torque from a legal on road use vehicle than the above then get an electric moped, there are some very nice models on the market.
Did u achieve the 32-33 kph on a custom build or a bike off the shelf?
sent via huawei P9
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