how many watts for a e bike
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Chalo
100 TW
080 said:
On a flat surface with no wind, if you aren't big or heavy, 250W will carry you at about 30km/h on a sporting road bike in good repair. If you subscribe to the errant notion that you need a fully suspended knobby-tired bike like some around here do, you can easily trim 10km/h off that number. Also keep in mind that no form of transmission will take 250W from the motor and put that same amount of power to the ground.
Pedaling is good for you, good for your bike's performance, and good for maintaining smooth relations with drivers and police in your area. It's not something to avoid. A good pedal bike is satisfactory without a motor, but a 250W e-bike is pathetic without pedaling along.
dogman dan
1 PW
Unless the bike is very aerodynamic, you will have to pedal much of the time. Ideal conditions rarely exist in the real world. Why is it that downhill you have wind at your back, but uphill is always wind in your face? Or so it seems at least.
Just a tiny bit of wind, and 250w feels like 50.
Just a tiny bit of wind, and 250w feels like 50.
Drunkskunk
100 GW
You should take a look at Kepler's friction drives. I think he was calling the Eboost. RC motor derived friction drives. Gear drives are great, but at very low power levels, the effeciance loss would be a problem, and the small motors run at much higher RPM, so they will need much more gear reduction inducing much more efficancy loss.
I believe the EU 250 watt limit is based on average consumption, so you're not limited to a peak of 250 watts. you can pull more on hills and accelerating.
I believe the EU 250 watt limit is based on average consumption, so you're not limited to a peak of 250 watts. you can pull more on hills and accelerating.
+1Drunkskunk said:
This is a nice design that can be removed from your bike in seconds.
Kepler
Some relevant threads...
speedmd
10 MW
This calculator may be a big help in your estimating. http://kreuzotter.de/english/espeed.htm
I looked up the West Australian laws today. 250watt MAX output should allow for around 350watt input@70% efficiency.
My bother(bother) in law is a mechanical engineer and has won comps for 350 watt recumbent trikes. He is convinced 350 watts is enough.
I was wary of direct drive to wheel due to friction loses on all those horses I am trying to tame.
Was thinking mount the motor to an steel plate, do one small chain drive as a first reduction then a second one down to the wheel via a second chain.
The Inlaw(outlaw) says the chains good for about 97% efficient power transmission. ie 3% loss.
Have now seen the e bike calculator and it was a big help. Bookmarked it.
What are the friction losses on the friction drive recommended? I would loose only 6%(????) with a double reduction chain drive.
Dogman, I covered 3.2km (GPS measured) in just under 10 min. This is about 19kph. This includes all the getting on and off, stops at side streets etc. I would need a little more to get to work, say maintain 25kph. I have specifically planned a flat route away from traffic as part of the "feasibility study". On the flat grade, no wind, 250 watt output motor I am hoping for 25kph. I was surprised how sedate 19kph feels.
Drunkskunk, the law in WA says 250watt max output. Thats what the news article stated that said power was being lifted from 200 watts to 250 watts. 50 watts. Gee all those extra horses. What will I do with my new found POWER.
I will check out the other threads. I sure do like the simplicity clean lines of the friction drive.
Thanks for all the help
My bother(bother) in law is a mechanical engineer and has won comps for 350 watt recumbent trikes. He is convinced 350 watts is enough.
I was wary of direct drive to wheel due to friction loses on all those horses I am trying to tame.
Was thinking mount the motor to an steel plate, do one small chain drive as a first reduction then a second one down to the wheel via a second chain.
The Inlaw(outlaw) says the chains good for about 97% efficient power transmission. ie 3% loss.
Have now seen the e bike calculator and it was a big help. Bookmarked it.
What are the friction losses on the friction drive recommended? I would loose only 6%(????) with a double reduction chain drive.
Dogman, I covered 3.2km (GPS measured) in just under 10 min. This is about 19kph. This includes all the getting on and off, stops at side streets etc. I would need a little more to get to work, say maintain 25kph. I have specifically planned a flat route away from traffic as part of the "feasibility study". On the flat grade, no wind, 250 watt output motor I am hoping for 25kph. I was surprised how sedate 19kph feels.
Drunkskunk, the law in WA says 250watt max output. Thats what the news article stated that said power was being lifted from 200 watts to 250 watts. 50 watts. Gee all those extra horses. What will I do with my new found POWER.
I will check out the other threads. I sure do like the simplicity clean lines of the friction drive.
Thanks for all the help
John in CR
100 TW
080,
Are you aware of hubmotors? The motor is in the wheel of the bike. For low power levels and a flat-ish route they're the champ. The route you're talking is noisy and generally not nearly as reliable. For legal power levels nothing is more simple than bolting a geared hubmotor in the front wheel, and the bike can still look like a bicycle and pedal like a bicycle with or without the motor. The really slick well engineered friction drive setup others have mentioned would be the route to go if your focus was low weight and being able to remove the system from the bike when you park. As long as security isn't an issue, then you're not going to beat a hubmotored ebike for commuting without setbacks along the way. China puts over 10 million new ebikes and escooters on the road each year, and almost everything except cargo trikes that need much lower gearing uses hubmotors for very good reasons.
Are you aware of hubmotors? The motor is in the wheel of the bike. For low power levels and a flat-ish route they're the champ. The route you're talking is noisy and generally not nearly as reliable. For legal power levels nothing is more simple than bolting a geared hubmotor in the front wheel, and the bike can still look like a bicycle and pedal like a bicycle with or without the motor. The really slick well engineered friction drive setup others have mentioned would be the route to go if your focus was low weight and being able to remove the system from the bike when you park. As long as security isn't an issue, then you're not going to beat a hubmotored ebike for commuting without setbacks along the way. China puts over 10 million new ebikes and escooters on the road each year, and almost everything except cargo trikes that need much lower gearing uses hubmotors for very good reasons.
dogman dan
1 PW
The simplicity of small planetary geared hubmotors makes a small cost increase worthwhile. They are best for the lower power applications, because an internal clutch freewheels when you want to pedal without the motor.
The controllers for those little gearmotors can be pretty cheap. I know you pay more for everything in AU, but big controllers bought straight from china can be as low as $50 USD, including the shipping.
I don't mean to say non hub sucks, if your motor drives the bikes chain, you get huge advantages in gearing. But as John pointed out, a little hubmotor is cheap and easy.
Sometimes though, the fabrication is half the fun.
Re the low power, I'm biased. In my USA state, my only limit is 30mph and have a drivers license. I often do ride using only 200w, and reach speeds of about 25kph on that much. But up a steep hill, or into a 40kph wind, I'll use 2000w. And maybe still only go 25kph.
I definitely vote for 400 actual max wattage input, but then ride slower so you don't look like more than 250. Then you have some more for that windy day.
The controllers for those little gearmotors can be pretty cheap. I know you pay more for everything in AU, but big controllers bought straight from china can be as low as $50 USD, including the shipping.
I don't mean to say non hub sucks, if your motor drives the bikes chain, you get huge advantages in gearing. But as John pointed out, a little hubmotor is cheap and easy.
Sometimes though, the fabrication is half the fun.
Re the low power, I'm biased. In my USA state, my only limit is 30mph and have a drivers license. I often do ride using only 200w, and reach speeds of about 25kph on that much. But up a steep hill, or into a 40kph wind, I'll use 2000w. And maybe still only go 25kph.
I definitely vote for 400 actual max wattage input, but then ride slower so you don't look like more than 250. Then you have some more for that windy day.
Sometimes though, the fabrication is half the fun.
I see you worked me out then!!!!!!! Just "owner built" my house. LOL
Leaning towards chain drive. I enjoy making and sidestepping the bill. I like the repairabilty of DIY. $1.50 per liter for fuel is good persuasion and two years of construction has made me want to get some quiet time to myself.
If I go chain drive I don't mind pedaling up to speed then using the motor to sustain. For me legal (or very close to it) easy to find parts for and some exercise is the balance I'm looking for. Now I have the time I find myself enjoying the making again.
I think, but I don't have a great deal of knowledge in this area, 350 400 watt motor with some sort of 2 stage non geared chain reduction. Pedal to get going. "Cruise" on the motor.
Thanks for the info
I see you worked me out then!!!!!!! Just "owner built" my house. LOL
Leaning towards chain drive. I enjoy making and sidestepping the bill. I like the repairabilty of DIY. $1.50 per liter for fuel is good persuasion and two years of construction has made me want to get some quiet time to myself.
If I go chain drive I don't mind pedaling up to speed then using the motor to sustain. For me legal (or very close to it) easy to find parts for and some exercise is the balance I'm looking for. Now I have the time I find myself enjoying the making again.
I think, but I don't have a great deal of knowledge in this area, 350 400 watt motor with some sort of 2 stage non geared chain reduction. Pedal to get going. "Cruise" on the motor.
Thanks for the info
friendly1uk
1 MW
I thought austrailia had a200w limit except where the european pedalec rules had been adopted. This would mean no cruising along at 25kmh because the motor can't run at 25kmh.
Why are you sticking to policy? Might you get in trouble?
I stay within common law. I cause no problems for other people, feeling where there is no damage done, there is no crime. I am not a slave or in contract with my government so policy should not effect me. I understand they will bully me in to doing things I shouldn't have to though, So I fitted a 250w controller. I can point to it as the brains behind my bike and then who has the right to question it further? To do so would require them to take it from me and employ an independent assessor. This having seen the controller labeled up as 250w. Who is going to authorise it? They can't have every bike they see independently tested. They are a registered business trying to earn money.
If you take a 250w controller and disconnect the limit wires most bikes will pass the 15mph (25kmh) mark and reach about 18mph unassisted (presuming the battery can deliver and the motor can take a little bit more). I think this might be a way forward for you.
Why are you sticking to policy? Might you get in trouble?
I stay within common law. I cause no problems for other people, feeling where there is no damage done, there is no crime. I am not a slave or in contract with my government so policy should not effect me. I understand they will bully me in to doing things I shouldn't have to though, So I fitted a 250w controller. I can point to it as the brains behind my bike and then who has the right to question it further? To do so would require them to take it from me and employ an independent assessor. This having seen the controller labeled up as 250w. Who is going to authorise it? They can't have every bike they see independently tested. They are a registered business trying to earn money.
If you take a 250w controller and disconnect the limit wires most bikes will pass the 15mph (25kmh) mark and reach about 18mph unassisted (presuming the battery can deliver and the motor can take a little bit more). I think this might be a way forward for you.
I live in Western Australia Unofficially labeled the "Nanny State". Most things are regulated such as where you can walk your dog what type of dog you can own, what part of the roof you may put solar panels on, cats are registered like firearms you can't own an airgun without a gun license, I have to wear a bike helmet by law, I can't use an e bike on a dual use cycle / footpath, I must be licensed to catch fish, sail a small motor dinghy on a river,(5 hp)
and e bikes are limited to 250 watts. They do enforce it. If you are caught you are treated by the law as if you were driving an unregistered and unlicensed vehicle. As silly as it sounds and as anti environment and common sense it is, that is what they do.
The law has been amended to allow 250 watts (up from 200 watts). I think that they were basically forced to do this a the "rest of the world" (Europe and parts of asia) has a 250watt limit and in this global market the 250watt drives were flooding in and they were not able to stop people using them.
I would have to actually check the laws which should have gone through by now but I am almost certain it is 250 watts and I think 25kph with motor engaged max speed in the Nanny State, West Aus.
If I went to about 350 400 watts input used your speed controller idea and rode safely and responsibly I believe I would be OK, as I should be within the law.
I have not heard of any prosecutions for an e bike. People are only just waking up to the fact that a very small motor and very light battery pack can provide power and range that was almost inconceivable 10 years ago. I don't think the police get that a motor the size of a coke can can produce 2hp. They do prosecute with great regularity the "pocket rockets" and two stroke bike engine users. Its only a matter of time for e bikes.
I like your thinking re damage or crime. It sounds like common sense to me. The crime bit is interesting because here if they don't like it they regulate it and call it a crime. A someone on this forum said elsewhere the masses have finally got they low cost technology to largely bypass their car so the government regulates it in such a way that people feel it is not a viable alternative to the car.
That said, anyone know of a good Hobbyking 350 400 watt outrunner motor that might suit chain drive with no gears. One off the motor then one onto the largest rear sprocket would get me what I want I think.
Matching speed controller would be good too, but the motor really is the great unknown for me.
I can make a light double reduction chain drive. I built my own well pumpjack to get groundwater using those methods so its old ground for me if I go that path.
Thanks all.
and e bikes are limited to 250 watts. They do enforce it. If you are caught you are treated by the law as if you were driving an unregistered and unlicensed vehicle. As silly as it sounds and as anti environment and common sense it is, that is what they do.
The law has been amended to allow 250 watts (up from 200 watts). I think that they were basically forced to do this a the "rest of the world" (Europe and parts of asia) has a 250watt limit and in this global market the 250watt drives were flooding in and they were not able to stop people using them.
I would have to actually check the laws which should have gone through by now but I am almost certain it is 250 watts and I think 25kph with motor engaged max speed in the Nanny State, West Aus.
If I went to about 350 400 watts input used your speed controller idea and rode safely and responsibly I believe I would be OK, as I should be within the law.
I have not heard of any prosecutions for an e bike. People are only just waking up to the fact that a very small motor and very light battery pack can provide power and range that was almost inconceivable 10 years ago. I don't think the police get that a motor the size of a coke can can produce 2hp. They do prosecute with great regularity the "pocket rockets" and two stroke bike engine users. Its only a matter of time for e bikes.
I like your thinking re damage or crime. It sounds like common sense to me. The crime bit is interesting because here if they don't like it they regulate it and call it a crime. A someone on this forum said elsewhere the masses have finally got they low cost technology to largely bypass their car so the government regulates it in such a way that people feel it is not a viable alternative to the car.
That said, anyone know of a good Hobbyking 350 400 watt outrunner motor that might suit chain drive with no gears. One off the motor then one onto the largest rear sprocket would get me what I want I think.
Matching speed controller would be good too, but the motor really is the great unknown for me.
I can make a light double reduction chain drive. I built my own well pumpjack to get groundwater using those methods so its old ground for me if I go that path.
Thanks all.
deffx
100 W
080 said:
Yes you can
1. Adults are now permitted to ride a compliant power assisted pedal cycle
(PAPC) on shared paths with the power engaged. To be compliant power
assisted pedal cycles must have a maximum power output of 200 watts
which restricts maximum speed capacity to approximately 25 km/hour.
PAPC’s are frequently used by older people and those with health issues
who have limited mobility and are not capable of riding a standard bicycle.
There has been no change to the rule that prohibits people under 16 years
of age riding a PAPC with the motor engaged.
http://www.transport.wa.gov.au/mediaFiles/marine/AT_CYC_P_ChangesBikeRegs.pdf
If your responsable, considerate, pedal, and don't speed at stupid times/places, your go unnoticed pretty much.
I am always surprised how ignored i am even on my beastly DH bike which isnt very stealth,
But i guess slightly bending the rules is a decision you have to make,
I live in the outer suburbs so probably not quite as much chance of being questioned opposed to maybe the city centre.
Either way 30km/h probably no problem, 60Km/h on the foot path your gonna get the popo's attension
I tend to cruise at 30kmh, its a nice normal cycle speed, and go fast after dark/back streets when roads are quiet
Hi deffx
where abouts are you? I will look up the actual legislation later. Something I have noticed in the past is the actual legislation differs to the warm fuzzy stuff they release to the public as press releases. At other times what they press release is more a hit list of how they want you to behave and is only superficially tied back to actual legislation.
I checked out the link. I am almost certain they have been upgraded again to 250 watt and no paths.
They did a press release and it was in the paper.The Worst Australian.
I will look at it when I get the time.
But what you are saying I think is good advice re speed and power and behavior.
where abouts are you? I will look up the actual legislation later. Something I have noticed in the past is the actual legislation differs to the warm fuzzy stuff they release to the public as press releases. At other times what they press release is more a hit list of how they want you to behave and is only superficially tied back to actual legislation.
I checked out the link. I am almost certain they have been upgraded again to 250 watt and no paths.
They did a press release and it was in the paper.The Worst Australian.
I will look at it when I get the time.
But what you are saying I think is good advice re speed and power and behavior.
Got my car going. So fuel filters right..................... they are important.
So the back up plan is sorted. Make e bike. leave for work early. Have the car for times when the wife has the other car and I need to drive.
Anyone know of a good Hobbyking 350 400 watt outrunner motor that might suit chain drive with no gears. One or maybe two off the motor then one onto the largest rear sprocket would get me what I want I think.
Matching speed controller would be good too, but the motor really is the great unknown for me.
I can make a light double reduction chain drive. I built my own well pumpjack to get groundwater using those methods so its old ground for me if I go that path.
Cheers.
So the back up plan is sorted. Make e bike. leave for work early. Have the car for times when the wife has the other car and I need to drive.
Anyone know of a good Hobbyking 350 400 watt outrunner motor that might suit chain drive with no gears. One or maybe two off the motor then one onto the largest rear sprocket would get me what I want I think.
Matching speed controller would be good too, but the motor really is the great unknown for me.
I can make a light double reduction chain drive. I built my own well pumpjack to get groundwater using those methods so its old ground for me if I go that path.
Cheers.
deffx
100 W
Hey 080,
I'm outback Waneroo/Joondalup. I don't think the 250w, no throttle and 25Kph rule has been passed yet by W.A. but it will. Though they will have to allow the old 200w bikes with throttle to still be allowed
There is lots of RC mid drive bikes on here, sorry i cant help you with these motors, but yes i believe you will need reduction unless you go friction drive (Kepler/adrian_sm).
You mention its for commuting, a hub motor or friction drive is probably a lot more reliable and low maintenance, KISS, than a rc mid drive
Also for commuting a light bike, just enough battery for the trip and a small/light geared hub motor or friction drive seems to be the conclusion by most people
Good luck with whatever you build and good to see another sandgroper on here, ebikes are a idea good in Perth with the large distances we have to travel
I'm outback Waneroo/Joondalup. I don't think the 250w, no throttle and 25Kph rule has been passed yet by W.A. but it will. Though they will have to allow the old 200w bikes with throttle to still be allowed
There is lots of RC mid drive bikes on here, sorry i cant help you with these motors, but yes i believe you will need reduction unless you go friction drive (Kepler/adrian_sm).
You mention its for commuting, a hub motor or friction drive is probably a lot more reliable and low maintenance, KISS, than a rc mid drive
Also for commuting a light bike, just enough battery for the trip and a small/light geared hub motor or friction drive seems to be the conclusion by most people
Good luck with whatever you build and good to see another sandgroper on here, ebikes are a idea good in Perth with the large distances we have to travel
Thanks for that.
I am just looking up the bike laws now.
My Brother in law says go with a 300watt input brushed motor with a chain drive and an on off switch. I'm thinking 300watt brushed with friction drive as i can change the size of the friction wheel as I have a lathe.(to gear the motor correctly)
On a tangent now but I plugged mt 240v grinder into my 12volt car battery and it did turn at about 300 rpm! Not sure about that or why it "worked". I don't know how much torque it made.
I am just looking up the bike laws now.
My Brother in law says go with a 300watt input brushed motor with a chain drive and an on off switch. I'm thinking 300watt brushed with friction drive as i can change the size of the friction wheel as I have a lathe.(to gear the motor correctly)
On a tangent now but I plugged mt 240v grinder into my 12volt car battery and it did turn at about 300 rpm! Not sure about that or why it "worked". I don't know how much torque it made.
Tinto
100 W
I won't ponder local regs on a public forum, but my peak hr commutes are uninterrupted on bike paths and roads,
Don't ride like a tool, pedal along always and you shouldn't have issues.
Perhaps something like this could suit you:
http://www.gngebike.com/36v350w-48v400w-gen2
I'm running the GNG gen 1.
Don't ride like a tool, pedal along always and you shouldn't have issues.
Perhaps something like this could suit you:
http://www.gngebike.com/36v350w-48v400w-gen2
I'm running the GNG gen 1.
