As Luke says - it is a start anyway. Commonly Asked Questions About BuildsWhat is an ebike?
An ebike is an ordinary bicycle with an electric motor that is also capable of being pedalled. Generally, the fuel for an ebike comes in the form of a battery others have also used capacitors but the range is very limited.How fast will an ebike go?
This depends on the type of motor, the internal motor windings and the voltage of the battery that is powering the ebike.
Here is a rough guide for motors according to wattage. 250 watt geared motor expect 25 kph (15 mph), 350 watt geared motor expect 30 kph (18 mph), 500 watt at 36 volts 32 to 40 kph (20 to 25 mph), 1,000 watt 45 to 50 kph (27 to 31 mph).
If you keep increasing both wattage and voltage much higher speeds, far in excess of 100 kph (62 mph), are possible.What types of ebikes are available and which one should I purchase?
There is ultimately only two types of ebikes available. One is a complete electric bike and the other, a do-it-yourself conversion kit.
The second part of the question is tricky. It depends on your needs and budget. Generally, conversion kits will work out cheaper as you can get better motors, better batteries, with increased range.
However, low-end electric bicycles are often cheaper than kits but often have low-wattage motors and batteries with very small ranges. This is also coupled with bicycles that are often quite poor quality. There are high-end electric bikes available but expect to pay a substantial price of several thousand euro/dollars/pounds.
Purchasing an conversation kits allows you to fine-tune the package to suit your needs. You can choose what type of motor, where it will be mounted, what type of batteries, what range you would like...The possibilities are endless. You can purchase a complete kit for as little as 700 euro/600 pounds/900 dollars.What range will the ebike do?
The range of an ebike is completely dependent on the battery. Factors such as battery chemistry and the capacity of the battery in amp hours determine the range. A good conservative rule of thumb is a two kilometres (one mile) per amp hour of battery at high speed. A ten amp hour battery, at higher speeds, will therefore have a range of 20 km (12 miles).
This method allows for other factors such as headwinds and hills to reduce the range of the battery. Both reduced speed and increased pedalling will increase the range. Note with that with Lead Acid batteries unless the battery has a very large capacity the range will be even less. Perhaps only 1kph (half a mile) per amp hour. The battery chemistry?
There are many types of battery chemistry with many more in development. There are two main types commonly available: Lead Acid and Lithium Ion.
People are generally discouraged from purchasing lead acid as it will end up costing the buyer more money in the long term.
Lead Acid has two advantages it is relatively safe and it is cheap to purchase up front.
But it has many disadvantages its C-rate is appallingly low .5 C which means to prevent voltage sag a lot of capacity must be carried.
Lead acid is also especially susceptible to the Peukert Effect which means that it will ordinarily only give half its rated range. So a ten amp hour, lead acid battery will only give out five amp hours capacity.
Lead acid is extremely heavy and having a large range means a huge amount of weight to carry on a bicycle.
It cycle life is also very short. At most a user will get 150 to 200 cycles out of this chemistry at using only 80 per cent of the batteries capacity (depth of charge).
Lithium batteries are currently the best type of chemistry, or more specifically chemistries, on the market. There are many variants each with different advantages and disadvantages.
Two of the most widely used are lithium cobalt which are generally referred to as Lipo and lithium iron phosphate, LiFePO4.
Lipo has a life of roughly 500 cycles which LiFePO4 has a life of 1,000 to 2,000 cycles, depending on the manufacturer.
Lipo generally has a higher C rate than LiFePO4 which means there are more amps at the riders disposal although A123 Systems LiFePO4 is on a part with most Lipo products.
Lipo has a greater energy density than lithium iron phosphate and weighs a great deal less.
Lithium iron phosphate is much safer than LiPo which can explode while being both over charged and discharged. Extreme caution should be used when using LiPo.
Lipo is much cheaper to purchase than LiFePO4 up front. However, over time LiFePO4 with its much longer cycle life works out to be more cost effective.
There are many benefits to using Lipo but this chemistry is far from ideal for ebike novices.What type of motors are available?
Hub (direct drive and geared), RC and Friction Drive motors are the most common types.Are ebrakes important?
This is not a straightforward question. It comes down to preference and what type of bike you have. For some people, such as dyspraxics, it may be prudent to employ ebrakes.
Others prefer kill switches that can turn the motor instantly off with the flick of a switch in case of emergency. Some bikes that have their brakes and gears in one system, revoshifters being a case in point, will be especially ill-suited for ebrakes.Are torque arms necessary for hub motors?
Correctly mounted torque arms prevent the motor from spinning in the dropouts which can potentially cause serious accidents, and perhaps even death, with the rider being flung from the bike.
The answer to this question is highly dependent on the amount of wattage motor is generating, where the motor is located and what type of material the bike frame is composed from. For safety's sake it would be wise to use torque arms on fork mounted, front motors, irrespective of how much wattage the motor uses.
Aluminium bikes should always use torque arms as the metal is more prone to breaking than steel (this can happen without warning). Rear-mounted motors on steel frames may not need torque arms if the wattage is low and the dropouts are well-designed. The most judicious thing to do would be to use torque arms regardless of mounting position and frame composition.
That is all for now. I will correct the inevitable mistakes later on. Too tired to read over it at present.