I am a new member to this site although I have been a ‘guest’ for quite some time. I have decided to join so as to try to be of assistance to all those new members who want information as to what is the best bike for them. I have also written it for all the guests who are watching this site hoping to find out the same thing. So here goes:
How to choose an ebike
The answer is surprisingly simple.
Just like you would choose an ordinary bike.
If you were buying an ordinary bike what would be the most important thing that you would need to know about it.
And the answer would be:
If I rode this bike would I be able to maintain the cadence that I am most happy with in the terrain that I will be riding it in.
Cadence is the speed that you normally spin the peddles. It is allied to the effort that you are comfortable with inputting.
It is an exceedingly important aspect of cycling because if you can maintain your preferred cadence over your riding time then you will cover relatively large distances comfortably without becoming unduly fatigued. Go outside your preferred range and you will tire quickly. Professional cyclists can maintain their preferred cadence up hill and down dale and they do this because the bikes that they ride have the gearing to enable them to do it. They will only step outside of this range, e.g. when standing in pedals, in the pursuit of speed and then only for relatively short periods like when they are sprinting for the line or when going for the ’ king of the mountains’ title for hill climbing.
The other choices such as bike type, wheel size, suspension and colour etc. are all secondary.
Now for the ‘electric’ motor bit. (which you are all interested in).
Notice that I have said here ‘electric’ and I have said it for a purpose. Electricity is a funny thing it can be tempted to leave ‘home’ but it cannot wait to get back! Electricity runs in circuits and if a circuit is broken it will try to bridge the gap and can jump large distances if it has the required volts. This aspect is important in the design of any electric motor. Ebike motors consist of a fixed stator usually made up of permanent earth magnets and the rotor, the moving bit, made up of thick copper wire the ‘windings’ that are wrapped around the individual metallic cores that make up the required number of electro magnets. It is through these coils that electricity is passed. When a core and its ‘windings’ reach a point offset from a permanent magnet the circuit is broken and the volts from the battery build up in the coils trying to bridge the gap, while all the while magnetising the core. The magnetism becomes greater the longer the gap in the circuit is maintained. Therefore an electric motor is at its most powerful when going at its slowest. It is a matter of ‘time’. The longer the ‘time’ that the volts have to magnetise a coil the more powerful the motor will be but there is a limit. If the gap remains open too long due to a lack of progress there is a danger that the coils packed with electricity will overheat and burn out and so a thermal cut out is often incorporated to prevent this.
There is a correlation between speed and power. The faster a motor can break and bridge the circuit gap whilst keeping the necessary level of coil magnetism to make the motor practical the faster the motor will go.
You may now ask how does the motor pack the windings with the necessary electricity if the time scale that it is allowed to do this in is so short at speed? This is down to the onboard computer and the battery management system the BMS. When a level has been set by the rider the computer tells the BMS the motor needs some more electricity to enable it to increase the speed and it does this by increasing the ‘flow’ of electricity thus allowing the coils to be able to fill up more quickly. Flow is measured in amps. Not all batteries are the same when it comes to how much current they can comfortably discharge and it is this factor alongside the thickness and number of turns in a coils windings that influence the maximum rating that a motor can output. The initial power ratings having been established in Law at 250W.
When the speed has been reached the onboard computer tells the BMS that it has reached the desired speed and it can ease off. It is the limit as to how much power the battery can deliver that limits an ebikes top speed. It is a carefully worked out compromise between a reasonable distance and speed and this should be born in mind when using full speed settings. When working in textiles as an apprentice Loom tuner I decide one day to speed up one of the machines. The Boss the next day wasn’t impressed even though I had it running as sweet as a nut. The reason being that the small increase in productivity due to the increase in speed would be offset by the large increase in his electricity bill for this is where one of the major laws of physics and one which seems to be ignored on this site comes in, as stated by a Mr Ohm or Watt I think and that was that any increase in speed is done at the square of the increase in power. Motor racing fans will be well aware of this as their teams strive to gain a half a second a lap advantage over their rivals. I have stated this for one reason, all ebike motors have a ‘sweet’ spot where they are at their most efficient in terms of power to speed. This may be a few miles per hour short of the maximum cut off speed and a speed where acceptable mileages can be obtained if this point is not exceeded. Wellying the bike to obtain a few miles per hour more really hammers the battery. Setting a high level to climb a steep hill has the same effect and is unnecessary unless the motor speed can be kept high and it won’t up a steep hill and if there is any advantage in setting a high setting it is negated by the loss of battery capacity. As has been said before on this site if you really need to be a boy or girl racer get a motorbike.
I have written all this because nothing is usually written about the power of a motor which is what gets an ebike up the hills. Governments don’t just pick a power rating out of the hat and say that that is what you can have whether it works or not ,like it or lump it, they set their scientists on so as to establish what rating an ebike motor needs to enable it to climb any hill that an ordinary biker could climb before getting off and pushing. Ebike motors with the same input from you effectively halve the hills steepness.
And that is it. I hope you will find this off assistance when choosing your bike.
I have obtained a Kudos King and I will write and post my experience of it in another post.
Yours sincerely
Linfitter:
How to choose an ebike
The answer is surprisingly simple.
Just like you would choose an ordinary bike.
If you were buying an ordinary bike what would be the most important thing that you would need to know about it.
And the answer would be:
If I rode this bike would I be able to maintain the cadence that I am most happy with in the terrain that I will be riding it in.
Cadence is the speed that you normally spin the peddles. It is allied to the effort that you are comfortable with inputting.
It is an exceedingly important aspect of cycling because if you can maintain your preferred cadence over your riding time then you will cover relatively large distances comfortably without becoming unduly fatigued. Go outside your preferred range and you will tire quickly. Professional cyclists can maintain their preferred cadence up hill and down dale and they do this because the bikes that they ride have the gearing to enable them to do it. They will only step outside of this range, e.g. when standing in pedals, in the pursuit of speed and then only for relatively short periods like when they are sprinting for the line or when going for the ’ king of the mountains’ title for hill climbing.
The other choices such as bike type, wheel size, suspension and colour etc. are all secondary.
Now for the ‘electric’ motor bit. (which you are all interested in).
Notice that I have said here ‘electric’ and I have said it for a purpose. Electricity is a funny thing it can be tempted to leave ‘home’ but it cannot wait to get back! Electricity runs in circuits and if a circuit is broken it will try to bridge the gap and can jump large distances if it has the required volts. This aspect is important in the design of any electric motor. Ebike motors consist of a fixed stator usually made up of permanent earth magnets and the rotor, the moving bit, made up of thick copper wire the ‘windings’ that are wrapped around the individual metallic cores that make up the required number of electro magnets. It is through these coils that electricity is passed. When a core and its ‘windings’ reach a point offset from a permanent magnet the circuit is broken and the volts from the battery build up in the coils trying to bridge the gap, while all the while magnetising the core. The magnetism becomes greater the longer the gap in the circuit is maintained. Therefore an electric motor is at its most powerful when going at its slowest. It is a matter of ‘time’. The longer the ‘time’ that the volts have to magnetise a coil the more powerful the motor will be but there is a limit. If the gap remains open too long due to a lack of progress there is a danger that the coils packed with electricity will overheat and burn out and so a thermal cut out is often incorporated to prevent this.
There is a correlation between speed and power. The faster a motor can break and bridge the circuit gap whilst keeping the necessary level of coil magnetism to make the motor practical the faster the motor will go.
You may now ask how does the motor pack the windings with the necessary electricity if the time scale that it is allowed to do this in is so short at speed? This is down to the onboard computer and the battery management system the BMS. When a level has been set by the rider the computer tells the BMS the motor needs some more electricity to enable it to increase the speed and it does this by increasing the ‘flow’ of electricity thus allowing the coils to be able to fill up more quickly. Flow is measured in amps. Not all batteries are the same when it comes to how much current they can comfortably discharge and it is this factor alongside the thickness and number of turns in a coils windings that influence the maximum rating that a motor can output. The initial power ratings having been established in Law at 250W.
When the speed has been reached the onboard computer tells the BMS that it has reached the desired speed and it can ease off. It is the limit as to how much power the battery can deliver that limits an ebikes top speed. It is a carefully worked out compromise between a reasonable distance and speed and this should be born in mind when using full speed settings. When working in textiles as an apprentice Loom tuner I decide one day to speed up one of the machines. The Boss the next day wasn’t impressed even though I had it running as sweet as a nut. The reason being that the small increase in productivity due to the increase in speed would be offset by the large increase in his electricity bill for this is where one of the major laws of physics and one which seems to be ignored on this site comes in, as stated by a Mr Ohm or Watt I think and that was that any increase in speed is done at the square of the increase in power. Motor racing fans will be well aware of this as their teams strive to gain a half a second a lap advantage over their rivals. I have stated this for one reason, all ebike motors have a ‘sweet’ spot where they are at their most efficient in terms of power to speed. This may be a few miles per hour short of the maximum cut off speed and a speed where acceptable mileages can be obtained if this point is not exceeded. Wellying the bike to obtain a few miles per hour more really hammers the battery. Setting a high level to climb a steep hill has the same effect and is unnecessary unless the motor speed can be kept high and it won’t up a steep hill and if there is any advantage in setting a high setting it is negated by the loss of battery capacity. As has been said before on this site if you really need to be a boy or girl racer get a motorbike.
I have written all this because nothing is usually written about the power of a motor which is what gets an ebike up the hills. Governments don’t just pick a power rating out of the hat and say that that is what you can have whether it works or not ,like it or lump it, they set their scientists on so as to establish what rating an ebike motor needs to enable it to climb any hill that an ordinary biker could climb before getting off and pushing. Ebike motors with the same input from you effectively halve the hills steepness.
And that is it. I hope you will find this off assistance when choosing your bike.
I have obtained a Kudos King and I will write and post my experience of it in another post.
Yours sincerely
Linfitter:
