I have no idea what I'm doing most of the time. But since you da man tell me something please.
I run two ebikes one has a 350watt motor with just a switch no controller. It works pretty well that way.
I have a 500 watt motor on a similar bike with a controller that seems to not do as well. I am wondering if the controller also limits the amps to those specified. IE a 500 watt motor should pull about 20amps according to the books. When pulling a hill it will actually pull more. I have blown 40amp fuses with the 500 watt before I put the controller on.
PS I had a controller on the 350watt but took it off because the performance seemed to suffer.....
Hi deacon, i know enough to hurt myself and thats about it, i am not a power biker, doing studies with a college project on why esc burn up so often, just cruising by and saw your post.
I can give some advice. Your example of a 500w motor pulling 20 amps, that is in a perfect world. Real life will indicate otherwise. Your current weight, day to day, air temp, road surface (this includes wet or dry) Grades, motor condition and how long it has been running, battery pack condition, max continuous and avg rated output of your esc.
ALL of that needs to be figured into your calculations for an avg AMP draw for a particular application. unless you have an amp meter to make some test runs to see exactly what you are pulling (and it will freak you out because the hi draws wont be when you expect them) you wont be able to make a good choice for motor or esc.
My suggestions: get an amp meter (or borrow one) and grab a cheapo motor or one you are familiar with and batery pack and esc, run a normal routine for a week, avg your amps, batt usage and motor temps (look at batt temps too)
with your readings purchase the best quality components you can afford that exceed the avg peak amp readings you recorded and avg peak temps (again the avg)
Keep in mind, throwing stuff together without doing the math (and there are tons more knowledgeable folks than i) even with a bike will result in alot of component failures or poor performance.
A cheat i use is this, see what working with folks with similar applications and copy it, then ask why it works. You will never gain knowledge or become an expert at anything unless you ask questions.
Good luck D!!