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Occasionally we get an enquiry asking "how much assistance does the extra power provide". The charts below should assist in this answer. By looking at what a 'normal' person outputs and then adding the power supplied by the auxiliary power, it becomes apparent the advantages of electric drive become apparent.
Some points to note:
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The average fit rider can output approximately 100W continuously. This means on a flat surface they could travel at approximately 22kph continuously.
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Note how low transmission losses can be. Some Hub wheel sellers will have you believe that is a major reason for not using chain drive systems.
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Most power is consumed by wind resistance on a flat surface. The faster you go the more power you need to just overcome wind resistance.
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Even the smallest of slopes/hills consume more power than all other losses combined.
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MOST IMPORTANT. These graphs do not show how wheel (or motor) speed will slow or more force has to be applied to maintain a given power output. Once a rider (or motor) reaches its maximum power output it will start to slow down until it stalls. THIS IS WHY GEARS ARE ON BIKES. As the rider reaches maximum power output, the gear is changed down. This allows the rider (or motor) to then continue operating at optimum power output without stalling. So by putting the motor in the gear train you get far superior overall performance when compared to a hub based system.
After viewing the graphs ask yourself "why go to a Power Assisted Bike"
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Go further with the same amount of power. Allows you to enjoy more scenery.
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Makes commuting far more viable as you can cover greater distances in less time.
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No licence, no registration, easy parking and Environmental Friendly.
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Everyone can ride a bike, so it is a real family transporter.
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The rider controls the amount of assistance provided by the Power Pack so exercise can be graded based on fitness, not terrain.
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Quiet and allowed on bike tracks.
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Excellent for those with long terms leg damage or convalescing.
Note the bike classification is specified as a Touring Bike and the combined weight of rider and bike is 100kg.
| This set of graphs represents the power required for various speeds while travelling on a flat road.
The graph below is the total of all resistances and losses needed to move the bike at a certain speed on the flat.
The graph below is a breakdown of all resistances and losses needed to move the bike at a certain speed on a flat surface. The point to note here is that WIND RESISTANCE becomes very significant as speed increases.
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| This set of graphs represents the power required for various speeds while travelling up a 5% (2.5 deg) incline.
The graph below is the total of all resistances and losses needed to move the bike at a certain speed up a 5% incline.
The graph below is a breakdown of all resistances and losses needed to move the bike at a certain speed up a 5% incline. The point to note here is that GRAVITY now leaves wind resistance 'looking good'.
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This set of graphs represents the power required for various speeds while travelling up a 10% (5 deg) incline.
The graph below is the total of all resistances and losses needed to move the bike at a certain speed up a 10% incline.
The graph below is a breakdown of all resistances and losses needed to move the bike at a certain speed up a 10% incline. The point to note here is that GRAVITY now leaves wind resistance 'looking good'.
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