For my senior ME design project I plan to build an electric motorcycle. My goal is to produce a bike that can go 60MPH and 60+ Miles per charge. I know these are very ambitious goals for home built bike but I do have all the wonderful perks that come with being an ME student--i.e. access to amazing labs and cheap materials. I am wondering if anyone can give me some input into how to accomplish a longer range. I understand that it is related to the amp-hours of the batteries and in general more batteries means more range--and more weight. Any suggestions or have you seen any high range builds around? I can't find many builds that get more than 40 miles per charge other than professionally available models. Thanks and any input/advice is very welcome.
-h
from what I understand , the bigest thing for a fast byke is to streamline the byke to reduce wind resistance or (drag), next reduce weight (Aircraft alluminum) , low center of gravity, match your power supply to the motor and controller, use the highest density battery with a high C rate ( c1= bat amp hr X 1 C5= bat amp hr X 5) 60ah cells X C5 = 300ah draw to the motor without destroying the battery. It will take some research to find the right combination and maybe a wind tunnel to test the body shell. Let us know how your project goes! LaTeR
thank GOD I wake up above ground !!!!
Gday HjFast,
if you are going the streamline route, make sure you dont increase the side wind area, or you will get blown around quite alot.
Id have to disagree re weight. yes a reduction in weight will (slightly, measureable but not significant) will increase range. However it makes it alot easier for you to be blown around.
bikes with a low centre of gravity dont corner aswell as those that have a high centre of gravity. a low centre of gravity bike will be easier to handle at low speeds, particularly by novice riders.
bikes with low centre of gravity have to lean further into a corner to create the same counter moment. A greater lean decreases the size of the contact patch, and thus the grip of the tyres.
cruisers tend to have a low centre of gravity, sports bikes have a high centre of gravity.
bikes have very poor aerodynamics. not alot can be done about it without affecting cornering ability, and ability to "hold the line".
60miles at 60mph will require around 7kwh.
60miles at 45mph will require around 4-5kwh.
what are you acceleration requirements?
what bike are you starting out with?
38 x TS90AH cells (or similar) would give you 10.8kwh (of which 8kwh is usable at 80%), and battery limited power of 25.5kw at 20 deg C, or 42.75kw at 30 deg C in 114kg.
combine with a big controller and say this hub motor: http://www.doingitall.net/EnerTrac/product.php
but anyway, lets hear more about your requirements or goals with this bike.
if 60mph for 60miles is your only goal, a maxi scooter is the easiest to convert (IMHO).
Matt
Daily Ride:
2007 Vectrix, modified with 42 x Thundersky 60Ah in July 2010. Done 194'000km