Electronics Mounting Bracket

I really wanted to come up with some type of electronics mounting bracket that would tuck all of the motor controller and other electronics up inside of the hollow gas tank. The tank would provide protection and still make the bike look half way normal. I created a pretty good 3d model of the bike frame and then made a solid model of the sheet metal mounting bracket.


Electronics Mounting Bracket


The electronics bracket is shown in red in the pic above. I was thinking I would send it out to be fabricated, but got a little impatient and spent a few hours Saturday and just fabbed it up.

Here's the actual Fabbed Bracket


 

 

 



I know it looks pretty boxy, but the tank still goes over it and covers everything.

Design Techniques- Kelly Johnson Skunkworks vs. 2013 Solidworks

I have debated on how to design and layout all of the components in the frame for quite some time. Is it more efficient to go to the  trouble to create a Solidworks 3D model of the motorcycle chassis or just do the old school trial and error. I finally decided that I can get through many more iterations faster and end in a more refined and optimized design if I go to the initial trouble and time investment to create the 3D model so I got up nice and early today and made a model. Take a look below.

 

 

 

I think this will be accurate enough to get the motor mounted and pack the batteries in. I will do some refinement to it to get the detail needed to create the electronics and controller mounts up under the tank. See below for a first cut at packaging the ME1003 into the frame. It really wants to be there. It looks like it really belongs there.

 



Throttle Details on Electric Motorbike

I ordered up a Magura throttle. It looks ok. It doesn't feel super precise, but it will probably work fine. I looked abroad the Web and didn't really see anything that looked awesome. The egress of the wire was a problem as i plan to use the stock kill switch assembly and the wire from the throttle ran right into it so i was able to cut a hole into the kill switch housing and run the throttle wire right through it where the old throttle cable once ran. It worked pretty slick and only required about 30 minutes with a dremel.

Supporting a Bobber Seat

The seat structure was cantilevered and was not properly supported. I added struts to triangulate the structure.

The Motor Just Came In!

UPS just brought the motor in. Here are a couple of quick pics...
It is the Motenergy ME1003. We bought it from Cloud Electric.

Fixing a Hacked Bobber

The back part of the frame had been hacked off by a previous owner leaving it looking very un-finished and sharp edged. It also did not have a proper mounting for the back of the seat (sort of important). See what we did below. Thanks to Josh from Fabtech for the late night work!
One more thing... The previous owner didn't run with all the motor mounts connected so one of the mounts broke off. Josh TIG'd that on last night too.

Fixed motor mount

Here is the before picture.

Another before picture, no way to mount seat.

 

Motor mount fixed.

 

 Here is what it looked like after adding a few parts

Here is the new seat support

The back surface will provide the mounting for the signal/tail/brake light



Just linked to www.invenscience.com

Since Invenscience is paying for the E-Bomb fun, we need to link to the Invenscience website and it is linking here. www.invenscience.com

Low Voltage Wiring

I retained the handle bar electrical controls for the most part. Bright, dim, signal, horn, engine stop will all be retained. I had to ring it everything and then change out the connectors to something that is readily available. I went with the Delphi weather pak stuff since i had some  around. Done of the signals were not needed and were isolated and tied back. I also retained the key switch and lobotomized it as well and changed to friendly connectors. See pics.

Big Day! Ordered the Motor and Controller

Today we ordered the motor and controller.
For the motor, I did a lot of trade study work and comparison. I really wanted a BLDC motor, but in the end, it added about $1000 in cost and I can buy a new set of brushes for $100 so I ended up going brushed, permanent magnet. Once the motor was selected, it made the list for the controller search pretty short. Here are the motor trades. I went with the Motenergy ME1003. For the controller, it was an Alltrax Axe 7245.

I bought the motor from Cloud and the controller from EV-Drives. There is a lot of variation in pricing on controllers for the same part number from different vendors. If you are doing this search, shop around. Check ebay too as I was able to save $193 on the controller buying it from EVdrives on ebay versus buying it off their website.

Its a roller!

With the rear rotor turned (thanks to Paragon Tool) and a new set of pads in the back and a new bearing, it will actually roll around and the brakes work on both ends. Wow! We are actually ready to start the electric conversion.

Dampener Issue Solved

After machining 3 iterations this morning, we got it right. Very little sloop and i think the polyethylene scraps we had laying around will work just fine.

Custom Torsional Dampener

After pondering the dampener overnight, I realized we ("Invenscience" since Invenscience is funding this project) have a sheet of black .750 thick PE. If I model something up quick in Solidworks and then we mill out a few wedges, we can probably replace the dampener in a way that will reliably survive.

Layout where the blue represents the wheel, red represents the hub and black is the dampener wedge

Dampener Wedge- 8 required

Gas Tank Bottom Looking OK

After cleaning up the cut with a 3"cut-off and adding some lip seal and flat black paint, it looks almost like the boys in the green factory in Japan meant to omit the bottom of the tank.

A Bit of a Snag

The torque dampener in the rear wheel is totally trashed. It turns out it is discontinued from Kawasaki and nobody had one. Not even Ebay. Bummer! Granted the power from the electric motor will be a lot smoother than banging through gears, but i need something to fill the gap. It doesn't look too bad until you realize that all of the material that is in compression during acceleration is totally gone.
What is to be done? Could make a mold and cast one out of urethane, but that would be a big investment. I think maybe the simplest solution us to machine one out of UHMWP. I could build it in segments.

High Level Trade Studies

I am doing some trade studies on various different approaches and thought some of it would be worth passing on to someone that might be tackling a similar project.

Keeping the Tank?

Why keep the tank on an electric motorcycle? On a bullet bike at least I have three arguments for keeping the tank:

1. Cosmetic- The big muscular looking tank adds to the tough look of a bullet bike. Take it off and in my opinion, it looks kind of dorky.
2. Storage- It makes a great weather protection and storage area for electronics if you cut the bottom out of it as I did.
3. In my case, it formed part of the mounting for the seat.

Exoskeleton

In my opinion, a bike with an exoskeleton is much better to work with for electric since you can stack lots of batteries in the center of the chassis as it gets rid of the obnoxious center tube that runs from forks to seat. The late 80's and 90's bullet bikes are great because they have the exoskeleton and many are aluminum. Mine is really pretty light once liberated from the 4 banger motor. I can easily lift the rolling chassis (before adding motor and batteries). I am hoping to keep the total weight to about 400 lbs. If it is approximately 150 now and I add 200 in batteries and 40 for motor, 10-20 for controller and misc. It should still be pretty close to 400 which is lighter that the stock 467 lbs.