Electric Bike Project

My latest project is my electric bike project.

My last attempt to motorize my bike was with a tiny 2 smoke engine from China that everyone calls the "China girl"  I call it the China piece oh-cwap!  Actually it wasn't bad and I did a ton of work on it before I even installed it.

I read on the motorized bike forum that you should do this, do that, and do blah, blah, blah.  I did that extra stuff and a lot more.  It fired up shortly after I got everything done and ran like a scalded dog.  I think I peaked out at 28 mph and that little beach was howling and screaming like mad at 5-6K rpm.  I actually road the bike to work a number of times then it slowly stopped starting.  I worked on it and worked on it and it just kept floundering until I had enough of working on it and just took it off.  This is what it looked like in it's prime.

So now enter the E-bike............

OK so after dealing with that gas bike I decided to pursue an electric bike or electric assist bike.  I scoured the web and found a few forums.  Then as I usually do, research, research, research, to find all I can about the subject and take a bit with a grain of salt.   One of my favorite websites is  Endless sphere.  I do have one issue and that they just keep saying go read, go read, it's like they don't want to answer any questions.  Many are super turbo electrical geeks or nerds.  Anyway, you can find a lot of info about electric vehicles from this website.

Hub motors can be for the front or rear hub.  There are a variety of standard sizes - 24V, 36V, 48V and watts can be 250W, 500W, 800W & 1000W.  Not all volts can take all types of wattage.  Typical hub motor size is like a 24V 250W, 36V 250 or 500W, 48V 500-1000W.  

After much reading and research I decided on a 48V 1000 Watt rear hub motor.  This unit has a lot going for it.  Both brakes have a cut out switch on them so as soon as you pull the brake the motor shuts off.  It has a throttle like a motor cycle.  A torque sensor that senses your pedaling and you can adjust the "help" from the motor from 1 to 5 with 1 being the least  help to 5 which is a lot of help.  There is a controller that has a rats nest of wires coming out and a computer controller that goes on the handlebars and a bag that goes on your rack to hold a lot of stuff.  Here are a few shots of my kit.

I got my kit off ebay but the company is YescomUSA and the price was decent and it looks to be a good kit.  My kit came with a disk brake which is what I wanted but after installation I found that it rubs on the frame in 2 places so I had to take it off.  I also would have to make a bracket to hold the caliper and just don't feel like taking the time or energy to do that right now.

The back tire went on fairly easy

and so I concentrated on a variety of other "things" to install.

Both brakes have a sensor that shuts off the motor when activated.  This requires removing both of the old brake levers from the bike and reinstalling the new ones.  Next was the throttle.  There are typically 2 types of throttles.  1 is a thumb lever the other is the twist grip like a motorcycle.  My kit came with the twist grip.  Finally up on the handlebar is the basic computer that shows battery level, miles ridden, time ridden, average speed, max speed, current speed and probably a few other things.  I have a regular Sigma BC800 speedo which I have hooked up so I can check the accuracy of both.

So I have 4 wires that need to go to the back of the bike (2 brakes, computer, throttle).  I used a  plastic cover, something you'd pick up at the local auto parts store.  This makes the wires look like one big bundle but very clean.

The other accessory I needed to install is the torque sensor which senses your pedal speed and allows you to either get a little or a lot of help from the motor when pedaling.

You can see the round disc by the pedal that had magnets which go by the red sensor and tells the computer what is going on.  (I took the bike for a test drive yesterday and found I need to adjust it - it doesn't work right now).  While taking all that apart I cleaned and repacked the bearing of the crank and cleaned the heck out of the sprockets & stuff down there.

Finally, I was ready to put the controller on the back of the bike (in the bag with the kit).  This little controller has a bazillion wires coming out of it and when finished I had all but 2 wires hooked up to it and I'm not sure what they are for so I did pretty good.

After checking out the bag I determined I needed to sew a little bit farther in the hole and extend it so I could get the wires through so into the kitchen where I had my sewing machine set up.

You can see there is what looks like a sign in the bottom.  It is a sign (not from God but a local crook - I mean politician).  Those guys are great for getting you these light weight signs to help form the base and sides of your bag. 

  After I did the bottom I decided I needed to do the same to the sides and back so now it is firm all around and very nice.  To hold it firmly on the back of the rack I used my soldering iron to burn some holes in the bottom where I used some zip ties to hold it firmly in place.

Next thing is the battery.  Like I mentioned earlier there are a bazillion different types, styles, sizes, weights, etc.  I decided early on that I wanted a Lithium Ion battery do to it's light weight to power output but with that comes a hefty price - KaCHING!  I searched high and low over the net and kinda found out that if you order an inexpensive battery from China (where like everything is made....)  you can almost double the cost for shipping and handling so a $400 battery is now like $800 - crazy.

After reading a variety of reviews I decided to order a 48V 15A battery in a case from Calibike here in the US.  This is run by Rafe Husain who sends out an Islam brochure which is a tad strange but educational so I took it as a learning experience which is what I think his intentions are.  Calibike is based out of southern California.  I had a few questions and shot him a few emails which he responded promptly.  The battery arrived in less than a week and I charged it up so I was ready to put it on the bike and get ready to go.  I also decided to get the one in the box because it looked like it had a better chance of surviving if I went over in a crash. 

This is a shot of the charger and part of the box (white on upper left).  It came with a couple of Anderson style leads.  I wanted to extend the leads so I had to get some 10 gauge wire.  When I went to solder them together I found out the leads had fine strand aluminum wire and of course I had normal copper.  I put a ton of solder on them and it wasn't as pretty as I'd like it is holding like no tomorrow so I'm happy about that.  A little bit of shrink tubing followed by electrical tape and I was good to go.

I did a test ride last night (2-23-15) and the bike ROCKS!  I zipped up a slight incline at 24.1 mph and it felt like the bike still had some umph left in it.  I'll have to get a little video up to show how well it works.

I still need to do some tweaking, like adjusting the brakes, adjusting the derailleurs, and the torque sensor but I'm pretty darn happy with how things are turning out so far.  I should get at least 1000 charges to the battery and then some which is great!

Now for some other stats.  The battery weight in the box was 12.2 pounds, the rear hub/motor weighed in about 18 pounds (normal wheel was about 6.5).  Not sure about the controller and other stuff but in all the bike weighs in at a hefty 62.8 pounds.  I'm guessing the extra weight was about 27 pounds which would make my bike about 35.8 which I think is normal.

Next thing is to make a bag for the battery to hang on the top tube to help distribute the weight and then I'll just charge and ride for a while to see how well everything works.

I don't want to sink anymore money into it until I can see that it is reliable transportation then maybe get a better quality electrical gauge that tells more about the battery and how well it really works.

First Real Ride...............   2-28-15

I took the inaugural ride up to Marysville WA to visit with Jeff Farnsworth and install some lettering on his beautiful boat and dingy.  I left way late in the afternoon but I really wanted to test out the bike and see what it would really do and what I really needed to fix.

Facebook photo of me, bike & dingy.

Well right off the bat about a mile from home my left pedal started coming loose.  I should have just turned around and went back - like a total space cadet I didn't bring squat for tools so I just pulled over and tightened by hand.  I ended up doing this a number of times on the way up there (8+ miles). 

Going across the flats from Everett to Marysville on hwy 529 I decided to open it up and see what she would do.  Well, I kept watching the speedo (both of them) as they kept climbing and climbing.  I'd seen 24+ a block from my house on the initial test flight but knew it could do more!  It did do more, passing 25, 26, 27, 28, and then it topped out at 29.9 mph - WOW!!!  I backed off the throttle and 16 felt like I could get off and push.

Some issues I encountered were the swinging back and forth of the battery bag while pedaling which I'll have to add a strap up front to wrap around the down tube to alleviate that.  Fix the darn pedal problem along with getting the torque sensor fixed so I can use that function. and get the darn derailleurs working properly.  I had the chain on the tree climbing sprocket up front on the way over which made me pedal like a mad man so on the way back I put the chain on the middle ring which helped out a LOT!  The back sprocket had the chain on the 5th gear and it was fine to just leave it there but I still need to fix the darn gear changing mechanisms.

When I arrived at Jeffs my battery "fuel" gauge had gone down 1 bar (out of 4).  I let him take it for a spin which he jumped at the chance and was zipping around his cul-de-sac like he was born on the thing.  I think we both were quite impressed by the little electric motor.

On the way home (after tightening the pedal) I felt it coming loose again at the south end of Marysville and stopped while I had some light at a gas station and did the finger tight game again.  Going across the flats was a bit spooky as I did not have a front light and going across 3 bridges with cars flying by at 60+ was a more scary that I want to admit.  At least I had a strobe on the back of the bike along with a bunch of reflective.  I'll be adding more tomorrow and bring along more lights just in case.  When I pulled in my driveway I had 1 bar left on the gauge.  I totally spaced on checking the voltage before I plugged it in (gel-head) but after 3 hours the battery was back up to it's top off voltage of 54.6 so I pulled it off the charger.

It was about 45 degrees when I got home and I was chilled since I had only a T-shirt and a tyek jacket on so I hopped in the hot tub and enjoyed the warmth.