250 watt motor
I have set my-self a project of converting my mountain bike into an electric bike.
I am watching a 250 watt motor on ebay for around £30.00
My question is would this motor be up to the job, of course I will be peddling as well, the motor would be used to help get me up hills.
What kind of motor would you recomend or use.
OK John... what are you going to accomplish with your converted mountain bike; ride the roads or go off-roading? If you want just a little pedal assistance on a flat surface road than a 250w and a 24v 10ah battery will do that. You can move along at just above normal peddling speeds with a little assist from the motor. If you have some big hills (or carry a lot of weight) then step up the motors wattage from 250 to 500 or greater depending on the hills (and weight). Do you want to go faster than peddling (hold open the throttle and ride without peddling) then step up the battery voltage (24 to 36 or 48volts); and if you want to travel a long distance then step up the battery amp hours (10ah to 20 or 30ah).
My daughter drives a hub direct drive 250w 24v pedal assist around in the yard. It is not very fast, just above pedal speed when using only throttle. It slows down a little on slight hill climbs (slows a lot on steep hills). My (110lb) 15 yr old drives an 800w 36v on the street. It moves him much faster than peddling speed and takes on all hills with great ease.
A big difference is your use... are you really going to peddle and use the motor a little (pedal assist)? do you want to sit back and let the motor carry you? How fast? How Far?? Or some combination in between. Are you going to commute, how far, how fast, what speed, what load, what terrain? Do you want to off-road.. tear up a trail, make some jumps, etc...
I suggest that you go to Youtube and watch videos of ebikes in action. Pay attention to the motor type & size, battery type & size, terrain, riders weight, bike size and the resulting effects on the bike ride.
Last edited by Pedidelic; 02-18-12 at 07:24 PM.
Originally Posted by Pedidelic
Thanks for the reply, here is exactly what I want
I weigh 190lb and I will carry around 10lb in a back pack.
I want to ride on road only and your right I want the motor to do most of the work, I can relax a bit and enjoy the ride.
I dont want to go silly fast, maybe 15mph top speed on a flat road
The furthest I want to travel is 20 miles to be safe, it is a 13 mile round trip to and from work with some pretty steep hills involved, I can assist the motor if needed by peddling, Im not completely lazy lol
I was looking round on youtube last night and checking out some of the conversions people have done, I have a good idea of the parts that are involved in a conversion, I just wanted someone who actually uses an ebike to really tell me what size motor will be good enough for my needs so I am not wasting money and upsetting the wife
One last question, appart from e-bay, where is the best place to get parts for ebikes from.
If you're talking kits, then there are a million places..
Depends on how much you want to spend..
36v 20Ah battery will net you 20 miles round trip at 15mph..
36v 500w motor kit will help you with the hills, if you pedal...
Total cost should be somewhere in the neighborhood of about $600.
I am bidding on a 500w motor, controller and throtle controler on ebay, just need to sort the battery.
Thanks again for the help.
I notice someone in another thread recommend a $2700, 250 watt, 12.5 amp battery ready-built e-bike to a poster who needed to climb hills. First, I can not afford that price. Second, I don't believe a small watt motor and small battery will tackle steep hills on a regular bases. Let's not get into what a steep hill is...
My bike is 800watt 36v 20ah. Usually I pedal to start off and then hit the throttle and coast... and repeat throttling and coasting. I don't pedal much on flats because i usually throttle my bike wheel faster than my chain sprocket speed. I am your weight and my bike slows slightly at hill crest (I hear the motor strain a little) so I add pedal power to help out. On flats it hits 20mph easy; and flies down hill, so I just let it coast no throttle/save the battery. I travel like this for approx 25 miles and the battery is not even half discharged. Honestly, my ass cannot sit on the seat any further so I have never tried. I recharge at end of day.
I recommend as large a motor and battery as you can afford or your laws permit. Why...? simply because it feels good to know that-that extra power is there should you need it!
I would also recommend that you consider a regenerative motor to capture battery power from down hill coasting.
PS Honestly, My wife gnaws on me and the kids' asses all the time. I could bring her breakfast in bed and she'd complain. She's just back from dinner out and is yelling about nothing right now. Do what I do, tell her to step off!
PSS After wife tried our e-bikes, she wants me to convert her bike to electric as well. Might do it if she is nice!
Last edited by Pedidelic; 02-18-12 at 08:13 PM.