Newbie looking for your help/advice

`greedpower,
Welcome to our V is for Voltage Community, and for the compliment. We are here to help in any way we can, it's will be part of our new Mission Statement.
There will be others with more knowledge than myself that can give you some very good advice, may I suggest you also look at Moderator Testing 01 - Chain Wheel Motor My1018 and Building E-Bikes Collaborative Hand Books.

Stleride
Moderator Team Captain

Moderators are dedicated volunteer V Team members who help keep your V Forums running smoothly and provide Forum Support.

With that small a motor, you probably won't be doing more than 15 mph. You could gear it to go faster, but acceleration will be horrible and you won't be able to climb but the slightest hills.

But, you can increase your range by arranging the batteries in parallel. You will be using all 4 batteries but have a system voltage of 24 Volts and 40 A-h total.

I think you can use any 24 Volt controller. Maybe I'm wrong here. There are a variety of cheap ones (plus chains and throttle) available at partsforscooters.com . I haven't tried it, but I'm sure they'll get the job done albeit not the most efficiently. There is usually a 3 wire input for the throttle, 2 wire input for batteries, 2 wire output for the motor, and other wires for brake shutoff, lights, etc.

Hi Greedpower,

I would encourage you to set and define some goals for building an ebike so that you and others, who are more than willing to help you, achieve those goals.

When I started out in building the MB-1-E (Electric Mountain Bike), one of the first things I did was to set some goals.
In my case, I defined these goals as:

Perceived Requirements for this conversion:
...Use existing Mountain Bike for the conversion
...Be Durable
...Ability to climb dirt/ gravel inclines
...Be light enough to lift into the truck and over obstacles
...Have a fairly good range
...Be easy to work on and maintain
...Keep the conversion cost down as much as possible. ($500-$700)

... now, I can't claim to have met all goals, but it did give me some direction and helped me zero in on what I needed to do to get started.

Actually, the whole process was a learning experience for me and the wonderful folks here helped me achieve those goals by sharing their experiences and collective knowledge.

If you can help us understand what it is that you want to build, then I have no doubt that we can help you get there.

If you read my blog, and the blogs of some others, including echuckj5 and sturdly, I have no doubt it will give you some insight into how to go about making an ebike that will give you hours of fun and perhaps even help on your commute or local travel to a great extent.

If I were you, I'd definitely check out the
Building E-Bikes Collaborative Hand Books

Decide what it is that you want to accomplish, how much you intend on spending, what your preferences are etc. and we'll help you get there.

Hope this helps,

Dave

MB-1-E
Electric - Bridgestone MB-1 Mountain Bike

Greedpower,

Your goals sound reasonable and achievable IMO.
If used as you say, with pedal assist, I think the range is possible, especially if you have the opportunity to charge when you get to work.
As for the throttle, I am using a 0-5k Magura Twist Grip throttle and really like it.
Haven't had any problems with it and it is holding up well.

I found that a high quality controller is worth the investment. I finally went with a 200A Alltrax AXE (programmable) controller which has been ideal for my 560W 24V motor and works great for the hill climbing that I need.
I certainly don't think that you need a controller of this size for a 350W motor but would suggest getting one that is rated for continued use at least 3-4 times the Amp rating of your motor.
I originally went with a Navitas 36-100 controller which was, unfortunately, not enough for my motor and use (I fried it going up a hill) ... but it might work very well with a smaller motor as long as you don't have to climb long hills.
I'm not sure if it is the right controller for a brushless motor or not, I didn't research that.

I'd try to find a controller with continuous amp rating somewhere in the range of 80-120 Amps if you can find one.
I'd also suggest being sure that you protect your controller and system with in-line fuses.

As for charging, I have a 24V system but charge it using a 12V charger.
I already had my 12V, 3 stage charger and didn't want to purchase another one, so I placed a DPDT switch to switch from 24V series (to run) to 12V parallel (to charge). It works very well although requires a bit more wiring and makes the system slightly more complex (more to go wrong).

Good luck, keep us posted and ask all the questions you like, perhaps some others will also chime in to voice their opinions.

Have you decided on how the motor will be driving your wheel?
How about motor RPM to wheel RPM ratio?

Dave

MB-1-E
Electric - Bridgestone MB-1 Mountain Bike

Your goals sound very reasonable to me, especially if you intend to help out by pedalling. When I pedal along with the motor at full throttle, I'm in the highest gear, pedalling VERY comfortably, no hard work at all.... and it adds about 5kmh to my speed, give or take, depending on conditions. The easiest system for quick removal would be a front wheel hub motor though. I can have my original stock front wheel back on in a minute with an extra 10 seconds for taking the battery off. The only problem is putting it back on and having to dip back into the ziptie stock to ziptie the motor leads to the fork :)
But you do seem to have a workable goal and you shouldn't have too much trouble....only thing is, like was said before...don't expect much speed and hill climbing torque out of a 24V system....better than pedalling, but crap when a guy with a more powerful system flys up the hill beside you while you are putting along.

Giant Stiletto Bike
500W Golden Motors 20" front wheel kit
185lb rider
Flat ground speed: 36.6kph (no pedalling)
Top speed: 44.8kph (no pedalling)