Electric Bicycle Motorised Battery Bikes Australia value-e-bikes.com.au e bikes
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MISLEADING CLAIMS


I get very annoyed by misleading claims by anyone... You know the sort from the big (Harvey Norman, Joyce Mayne type, anywhere with carpets or tiles) retailers claiming "everything reduced, must sell today, 50% off etc" when we know that all the every day prices are "reduced", and that the same products will be there next week, and that there will be another sale on, and on, and that they never sell anything at 100% price. The advertising laws say "off" must be off normal price, but carpet sales are always 90% "off"... off a price that noone has ever paid. And they get away with it. Those false claims are all around us... in every product we buy, and we have become so blase about advertising that lies. That ubiquitous black drink claims "you can't beat the feeling" (can't? yes, I can, feeling good doing many enjoyable things, and so can you!). I hate all the lies, and could go on and on, but I should stick to claims about bikes.


RANGE OR DISTANCE

Obviously that depends on whether a battery does actually produce 10AH of energy. And many do not. Assuming that it does, the distance that it will take you depends on many factors, the biggest being how much you contribute to the going. The more you contribute, the less that the battery contributes, and the further it goes. The only way to test and compare is to go on same route at similar speed and with no assistance. Very few testers do that. I do test a sample of bike battery combinations. To this day I do not know of any other e-bike retailer who does. They simply quote what the Chinese bicycle factory claims. For one of the bikes another place has they claim range being "up to 100km". They may as well claim "up to 1000km" (if you do all the work).


BATTERY LIFE

So many new battery factories are starting and all are trying to get business. I get several emails every week trying to get me to start doing business with them. They too will try and cut costs with inferior BMS card or cells. I know there are a lot of inferior batteries imported here. All the factories claim that the batteries last 800 cycles for Li-ion or 2000 cycles for LiFePO4 (before degrading to an arbitrary 80% level). I doubt most have actually done that test on a battery that is the same as they sell. Even so there is a difference between rapid charge/discharge cycles in a laboratory to what you will get after 5 years on the road, with various factors affecting power retention. It would be more help if batteries were tested under a standard test simulating "real life". For instance, parking a bike in the sun, as many people do, reduces battery life. Be wary of 800 or 2000 charges claims.


POWER VS TORQUE

The particular offender here is Aseako. Their web site is very misleading.
Their bikes have a motor that drives the chainwheel. The motor has a reduction gear so that it drives the chainwheel at a speed matching the usual cadence of a rider.
Their motor is 200 watts like so many others but they try to confuse by claiming it has so much more torque than a hub motor. They claim it has 109NM of useful torque.
It does not have, and it cannot have 109NM of useful torque.
They talk about torque as if it is what gets a bike uphill, or to go faster. It simply is not that. It is power alone that does that.
Torque is the turning force that wants to make (for instance) a shaft rotate. Power is torque multiplied by the rotation speed.
For a given power output the faster a motor goes the less torque it provides. A motor can be geared up or down so the shaft delivering its power is faster or slower than the motor itself. The power output stays much the same but the torque of the output shaft can vary greatly. On the other hand a fast revving motor with low torque can be geared down to produce similar torque as that of a slow revving high torque motor.
The torque is magnified in the ratio of the gearing. That is what happens with the internally geared e-bike motors. It is only the torque actually applied to a driving wheel, that matters.
If you need to calculate the power you need for a given speed, I have several worked examples in blog : electricbicycles.me
Gravity is the main force that has to be overcome going uphill, obviously. At slow speeds the other forces (wind and rolling resistance) are small. Gravity force is known and is almost the same anywhere on earth.
It is easy to work out how fast any power of a motor will take any weight up any slope of hill. For example :
Put a 75kg rider on 27.5kg Aseako bike with 200 watt motor on 30 degree slope and bike speed will be 200 /102.5 * 9.81 * sin30 = 0.40M/sec = 1.4 kmh ...
at which speed the 26" wheel will be turning at 11.6 rpm ...
and with 48:28 ratio chainwheel is turning at 6.7 rpm, and at that slow speed the motor will be struggling and running very inefficiently and not be able to output 200 watts.
So, I say that 200watt motor will not be able to take a rider up a 30 degree slope, and even if it could it would be at about 1/4 of walking pace, and in practice you won't be able to ride so slowly anyway. Their claim "Aseako Electric Bike has far superior speed and power than its peers" is not true, and they should know that. I suggest you wait until there is proof of those claims. I take the Aseako Central Drive claims apart on this page


BEST BIKE

"Best" is a very subjective term. In an extreme case competitive road racer will spend what seem to ordinary bike riders enormous amounts to save a few grams, in a frame, or component. "Best Value" is a little less subjective because it easier to decide if it is worth $10, $100 or $1000 to save 1 kilogram. All the bikes are assembled by someone. No factory makes all the parts. The factory makes-to-order offering a range of parts quality from "Chinese" or "Taiwan" to "best", and no electric bicycle in Australia has "best", although some claim that. From the bicycle factory there is not a great difference in cost between good quality and very ordinary parts, and it is worth paying a little more for these, and I do. There are thousands of bicycle factories in China and they are all scrambling against one another to get export sales. Many of them will save a dollar with cheap pedals, or a few dollars with a cheap battery, and some of them will get a sale because they are cheaper. Every day every e-bicycle importer will get offers from a new factory in China offering competitive rates. Any claim of "best" cannot be taken as fact. Only time will tell which are good, better or best. I've seen some claiming to be best, when I know that they are not, believing mine at least are better. People Google for "best electric bike" or even "best electric bicycle in Australia" for instance, and some words like that need be put somewhere. If I claim "best bike" it is in context of best bike for you, it being a light folding bike, for instance.