Tres Chic

The rear support for the Upper Battery Tray is done.  It joins the rear of the tray to a rectangular cross piece that ties the frame rails together.  The piece required about 105 degrees of bend, which my tooling is not able to do, so I had to fudge the last 20 degrees. You can see where it doesn't sit flat along the cross piece, but through the miracle of modern coping techniques, I will live with it ( 1 deep breath and repeat "not everything can be perfect" 10 times).

The rear support piece requried four bolts thought the rectangular section, where I had previously mounted the controller.  So I will need to figure out how else I mount the controller and ther rest of the electronics.  Another goofy thing is that the whole tray seems to be skewed to the left side of the frame (look where the support joins the tray), but I can't see what is causing that, except that front frame rails are not exacly parallel.  The good news is that there is plenty of material on the rear tab of the tray, and you need to allow for such variations in a kit.

My lithium pack models fit fine on the tray.  The cardboard models simulate 12 Thundersky 60 AH batteries in the upper tray and 8 in the lower tray, giving an approximate 60volt setup.  I designed the trays to have enough room for Lithium Modules made of 5 units.  The model batteries were originally made to simulate modules of 4 batteries, but ended up too long by almost 1/2".  There should be enough room to squeeze in 24 cells, for an effective 72v system, but it's going to be tight in the back of the tray.  I can worry about that more when I can afford the lithium batteries.

Tres Magnifique (almost)

I got the upper battery tray cut and bent, but ran into a few hiccups in the bending process

After bending the front and rear tabs, the part will no longer fit into my bending brake, so I ended up finishing the bends in a vise.  The bends forming the side tabs are not uniform and the flat area where the batteries are supposed to sit is distorted.  The good news is that this piece is functional.  I will need to make a few changes to my tooling in order to accomodate future versions. 

I've also come to the conclusion that 3/16" stock is just too thick.  On version 2.0 all pieces will be made from 1/8" material.  This will help reduce the raw material costs and will be a lot easier to work with.  It also will save a little weight.

Fun with Paper & Glue - Upper Tray Begins

(Editorial note: this entry is for the absolute beginner and my documentation.  Experienced EV builders can skip this one)


In working with the sheet metal pieces, I've developed a system of modeling and checking fit without having to cut metal.  It's pretty common in the EV world to do Cardboard Mockups, but here's my take on it for sheet metal.
Model the sheet metal part

Print a full scale version of the flattened 3D model. In this view the flattened model has the bend lines and some additional construction lines to indicate where the curved surfaces will start, since I'm creating sharp creases, rather than gradual bends like the the actual part.

 Use spray adhesive to adhere the Print to some Posterboard and and trim the outer shape.  It's important to let the glue dry overnight while laying flat. When dry, use a straightedge to make straight creases along the fold lines.

Using the Posterboard model, I can get a feel for how things look and fit.  Obviously, it's a lot easier to make adjustments in paper.  This is the 4th verision of this particular paper part, and I'm finally ready to cut the real thing in 3/16 Aluminum sheet (5052 alloy).

Mounting the Shield

Finally got around to mounting the Shield.  I had planned to use the original motor mounts and have the bolts thread from the outside to the threaded bosses on the interior of the frame.  Problem is that the threads are lined up horizontally, and the surface I'm fastening is about 12 degrees offset.

I had to make a decisions to backtrack on the purely "bolt in" philosophy, but I figure anyone converting thier bike should have a drill and a grinder. I ground the motor mount bosses down close to the frame, but not too close as to remove all the welded material.  Then I clamped the shield into place and drilled holes slightly bigger than the existing threads (5/16"). The holes are perpendicular to the frame surface, positioned so the drill reamed out the threads at the new angle.

I then clamped the Tray to the Shield, drilled four holes, and threw in some 1/4" grade 8 bolts.  Eventually, I will probably use some stainless button head screws but, for now I like the looks of the gold colored grade 8 hardware.

Lower Battery Shield

My earlier misfortune with the plasma cutter turns out to be a blessing in disguise.  I had second thoughs about having relief holes on the frontward facing piece of the battery tray, because I would like it to protect the batteries from road debris and water.  This functionality prompted me dub the piece: "Shield".  I decided that using 1/8" sheet instead of 3/16" was accepble for the Shield, beacuse it's not really expsosed to direct flexing loads like the Tray. Even the 3/16" might have been overkill on the Tray, it's overly stout.

The  end result looks pretty decent, and even though it's 1/8" thick, seems plenty strong.  In hind sight, I would have liked the mating tabs between the Shield and the Tray to overlap a little bit more, but it's certainly functional.

I had intended to bend the top tab over at 45º, but I kind of like how it fits between the old oil-cooler mounts. The two piece design of the lower battery support system allows me to remove the Shield in order to load the batteries or perform maintenaince.  Now to drill some holes to mount it to the frame and the tray.

Beauty is Skin Deep

I had a slight malfuntion of the Plasma Torch in cutting the second piece of the lower battery tray.  The vertical axis was having problems lining up, but I decided to give it a shot.  Wrong move.  The torch made contact with the stock and drug it around on several moves.  I could only watch in horror as my precious 5052 sheet was sliced into semi-random chunks.

Time to order more aluminum sheet.

In the meantime, back to the cosmetic pieces.  The fairing is pretty trashed, but staying with my mantra of "use what ya got" for this phase, it had to be sanded and painted.  The sanding was complicated by several sloppy repairs of cracks with some nylon material that didn't bond well to the ABS.

The upper fairing turned out pretty decent, so I may even keep it.

Progress At Last - Lower Battery Tray

Buoyed by the completion of my new bending brake, it was time to tackle the big kahuna:  the Lower Battery Tray. 

Back to the plasma cutter I went

I crossed my fingers and held my breath as I loaded the swiss-cheese like sheet into the brake.

The first bend was one of the two longest ones - could the brake handle a 12 inch long bend? 

It held up like a champ, but the leverage required for the bend almost flipped my work bench over.

The icing on the cake?  The tray actually fits!

 

Of course this piece is only half of the lower tray.  A vertical piece will join the front of this piece to the frame, but that should be a piece of cake. Right?

Bending Brake Redux

Honestly, how long did I think a bending brake made of wood was going to last? It broke while making a bracket for the front fender on some 1/8" aluminum strip. So for the last two weeks, I've been making Brake v2.0 using Aluminum Channels, Iron Pipe, and a heavy duty steel hinge. (design inspired by Dave Clay: http://www.ch601.org/tools/bendbrake/brakeplans.pdf)

Nuff said~!

Battery Tray Trials

Given the capabilities of my bending jig, I decided to make the lower battery try in two pieces. The bends were too complex for my rudimentary tooling. Here's the redesign of the piece. I've added some notches along the edges to help align the part in the jig. I also added some relief holes, as a way of reducing effort needed to form the bends.

On the cosmetic end of things, I refinshed the front fender. In the sanding process, I discovered several layers of paint: Metallic blue, maroon, white, and royal blue at the bottom. Unfortunatley, the fender is not from this model of GSXR. Could possibly be from a '90 model like the fairing, but who knows. I guess some mounting brackets will be in the works next.

More Cosmetic Procedures

I'm slowly working my way throught the boxes of parts that I pulled off bike. Funny, it sure seemed to come off a lot faster thant putting it back on.

I decided to recover the seat because it wouldn't cost much and makes a big difference cosmetically. Also visible in the pic is the latest mock up of the lower battery tray.

Weight Watchers

My first attempt at a bending jig (can't really call it a brake), was barely able to bend a two inch wide strip of 3/16" aluminum. No way it is going to handle the nearly 12" required on the tray pattern. Granted the jig was only made of wood (oak I had laying around) and I was bending 6061-T6, but I was amazed and how much the clamping mechanism flexed during the bending process. The radius was pretty clean though, and there was only a minimal amount of micro-cracking, so I'm on the right track with the size of the bending radius.

In the absence of any real progress on the lower battery tray, I decided to start putting pieces back on the bike. While cleaning the rear Foot Peg Brackets, I noticed the large amount of material devoted to supporting the muffler and the seat lock. I really don't need the muffler mount and I never liked the seat lock setup. Time for a little weight losss surgery.

Like any good surgeon, I outline the sections to be removed with a sharpie. Armed with only a butter knife and ignoring the patient's requests for anethesia, I got to work reforming the brackets.

Ahhh... trim and sexy. Now about that butt lift Mr. Gixxer....

One step forward, Two steps back

Well, I thought I was making progress on the lower battery tray. The concept is a single sheet of cleverly cut and bent aluminum to form a "belly pan" that actually is a tray for holding batteries. I've got an initial 3-d model designed and printed ready to mock up.

The issue comes down to bending radius. The recommended minimum radius for bending 5052 Aluminum is .5 to 1.5 times the material thickness. With my 3/16" sheet, I figure that a .25" radius is about as small as I want to go. In discussing bending capabilities with the premier bending shop in the area they only had small radius tooling on their Brake, admitting that some cracking will occur at the bend.


I'm not to0 wild about cracks in my battery tray, so I will be building a homemade Brake on my workbench. Another project within a project. Obsessive? Anal Retentive? Ridiculous? Sometimes it's a gift, most days a curse.


I bent a 2" strip of 3/16" aluminum (6061-T6) in a vise using vise grips and small aluminum plates with a rough .25" radius, just to get a feel for the force required, and judge the bracket layout better. It took a lot more force than I imagined but turned out pretty good. Even with the .25" radius tooling, there were lots of micro-cracks in the radius, but that shouldn't be a problem with 5052 since it's more pliable.

Controller Crazed

My Alltrax 7245 controller and Magura throttle came in from Cloud Electric. I love blue anodized aluminum. Too bad the contoller will be tucked away under the tank.

I had initially thought of centering the contoller in the fuel tank area, but that would require an addtional cross member to support it. By using the existing cross member, a thick walled piece of rectangular tubing, the contoller is located toward the back of the fuel tank. That will free up the front of the tank for other electrical components and cables.

A little frame modification was required to have access to the inside of the rectangular section. There was already an opening on one side, I just needed to duplicate the opening on the left to allow room for a wrench and to get the bolt placed. The section of the tubing is almost 3/8" thick so I'm not too worried about affecting structural integrity when removing another piece.

Gettin' the Blues

I'm still in the process of designing the lower battery tray. So far, I've gone through dozens of revisions in the solid modeling program, a tedius and frustrating process. Against all the recommendations of my fabrication advisors, I'm leaning toward a single piece of 3/16" Aluminum plate with strategically placed bends. It's a Gixxer - it's got to be aluminum.

Patience is a virtue, but no hands-on activitities on the bike were gettin' me down. I decided to paint the tank. I was going to fix it up right and have it shot with automotive paint, but the tank has had more work done than Joan Rivers. Multiple layers of body filler and primer were evident in several areas, so I decided to go cheap on this revision and save my money for some AirTech pieces.

Rustoleum's finest Blue is fairly close to the color of the motor and just what the doctor ordered. Careful observers will note the lack of stupid looking vent cap and tubing on top of the tank. A friend of my sons recommended I turn the vent assembly into a beverage dispenser! While entertaining, I thought some form of ventilation would be a good idea. A small mag-lev fan will do the trick, I hope.

Action Flick

I just had to do a quick connect with 12V to see the rear wheel turn under battery power. Most triumphant!

The battery's I used are some burned out SLA's from a UPS. I've been placing them on a charger to see if they can be recovered, but they wont hold a charge over 13.2V. Good enough for the demo and testing phase though.

Holy Oversized Sprockets Batman!

In order to maximize acceleration, I needed the biggest rear sprocket that would fit. I measured the clearance avialable on the swingarm and a 71 tooth sprocket would just barely fit. So to give myself a little extra room, I decided to go with a 68 tooth unit. Combined with a 12 tooth in front, the gear ratio of 5.66 is a little high, and will sacrifice top speed, but I'm not too interested in going on the freeway. If I decide freeway speed is needed later, I can always put in a 14 or 15 tooth front sprocket.

The front sprocket and chain arrived from Grainger a few days ago, but the rear sprocket from Sprocket Specialist was taking it's sweet time. After finally arriving, I nearly choked at how big the sprocket was. Had I made an error calcualting the sprocket size? I estimated the 68 tooth sprocket at 13.75" diameter, but it looked like 16" to me. You know that saying "measure twice, cut once"? Well I'm famous for cutting twice, and sometimes more.

A tape measure told the truth: 13.875" (whew!). Still looks pretty big to me.

After putting together the hub and sprocket, I threw the rear wheel in place and cut the chain to length. Sprocket has a least 1/4" clearance from the swingarm, the chain fits and lines up just fine. Even the mislocated bolt pattern for the motor is not going to be a problem.

At this point, I'm feeling a little lucky and may go buy a few lottery tickets.

Motor Mount v2.0

Ok, so it's not completely bolted up yet, and there are still a few hiccups to iron out on the final design, but the motor mounts are on!
You might notice the extra hole near one of the bolts for the motor face. Oops, the dummy running the mill forgot to zero the x & y axis before moving to the position for the first hole. To cover my mistake, I ended up rotating the bolt pattern 14 degrees, so now the chain will have less clearance for the mounting bolt closest to the swing-arm.

I'm also not thrilled about the flanges I bolted on to provide a clamping action around the motor, as they look a little cheezy. I would have been better served by a couple of pieces of 3/4" x 1" aluminum stock.

Another lesson learned: plasma tends to cut features about .075" smaller that drawn, so I ended up doing a lot of handwork to enlarge the internal diameters on both brackets.

Plasmarrific Motor Mounts

So it turns out that the tapered plasma cutting path was indicative of a worn electrode and nozzle. With a fresh electrode and nozzle, I gave the plasma cutter another shot.



Another lesson learned from the first go-around with plasma is to orientate the pattern so the more accurate side is facing up. In my case, the left bracket was cut with the side that faces the motor on top.

Motor Mount Mishap

After countless paper and wooden templates to get the motor mount shapes and hole patterns just right, it was time to give it a shot on the real stuff. I ordered a chunk of 3/8" aluminum plate. Using the CAD drawings, one of the guys at work helped me cut the basic profiles on the CNC Plasma cutter. I was totally stoked looking at this complex geometry that took about 60 seconds to cut out.

Unfortunately, my elation was short lived. Several edges of the pattern were severely tapered, so even though the shape was perfect on one side, it was off by almost an 1/8" on the other side. I knew the shape cut by the plasma would be a little rough and had adjusted tolerances accordingly, but it hadn't occurred to me that the plasma would cut at an angle. It's possible something needs to be fine tuned. If that's the best plasma can do, I may need to rethink the manufacturing process.

Once the outer and inner profiles are cut correctly, I will use a mill to precisely drill the mounting holes for the motor and frame. Just for kicks on this piece though, I drilled the mouting holes using a paper pattern as a guide. Of course the holes for the motor didn't quite match up, so all I could do was bolt the bracket to the frame to see if it's close.

A little dissapointing, but not too bad for the first go round.

Re-assembly Begins

I've been asked why bother to strip everything off the bike and go throught the tedious work of cleaning all the little pieces. First, I'm anal retentive and have to. Second, there's no other way to know what's missing, worn out or broken on a 20 year old bike.



I cleaned all the pieces of the rear suspension and put it back together. Initially I thought a spacer was missing on the linkage lever. Turns out it was assmbled incorrectly, and judging by the wear in mating aluminum pieces, been that way for a while. You can see how much more of the left spacer is exposed. While not catastrophic at this point, addtional wear could definately be a problem.





I have gone through several iterations on the wood patterns for the motor mounst and got the design close. I'm confident in the hole locations for the motor, but not too sure with the bracket locations on the frame. I needed a more accurate template to work with. The cheap solution was a piece of 3/8" x 1" aluminum bar with a printout of the only the frame hole pattern pasted on. After a couple of more tweaks, I should be ready to cut the actual 3/8" plate.

Spring Break

Due to comittments with our local Little League Baseball program, I will not have much time to spend on El Gixxer until summer.

I've done several more wood patterns for the motor mounts, tweaking various features. The latest version uses slightly bigger hoop to go around the right end of the motor (actually closer to the middle). The loop will be cut and some angle sections added to make a clamping mechanism.

I did have the opportunity to read "Powering the Future" by Tom Koppel. It's the story of the Ballard Fuel cell, and at the time it was written (circa 1999) the Fuel Cell was hailed as a revolution in automotive power. Although still viable, the infrastructure for Hydrogen or Methane to power the fuel cells is lacking and killed the momentum behind it. It's a powerful lesson to those of us that think EV's are ready to take on the world.

Measure Twice, Cut Once

I've been unable to focus on anything else but figuring out how to secure the right side of the motor. My preference is to use the same material that I use for the left mounting plate, 3/8" aluminum. The first trick is that bracket has to be two pieces or have notches for the pole screws so it can be slid on from the left. The other gotcha is there has to be some clamping mechanism to secure the motor.


I came up with this basic design a few days ago, but dismissed it because two 3/8" brackets will be fine to resist motor torque and vertical/hoizontal loading from the chain tension. But loads parallel to the shaft need something else. It came to me this morning, add an angle bracket and use the mounting holes in the case. (edit one year later:  no additional pieces needed, the dual bracket arrangement is plenty strong with regards to axial loads.)

I was so jazzed at having a solution, I cranked out the template to make the wood prototype. I also tweaked the geometry on the left bracket, thinking I could cut them both and have the wood parts done. Haste makes waste...

I neglected to check if I had enough RotoZip bits
and busted my last one starting the new bracket. I did manage to cut out a sloppy version of the left bracket, so at least I could get it fitted. Wrong-O! In adjusting the bolt pattern location, I appearantly changed the bolt circle diameter, making that version completely worthless. The only bright side of these wasted efforts is that it's only wood, not the actual 3/8" Aluminum.

Motor Mounting v1.01

When I actually positioned the motor inside the frame, I could see that my earlier ideas for mounting the motor were not feasible. The motor is offset much further to the right side of the frame than I had envisioned. I will have to go with a face mounted bracket on the left side, and some type of clamp or belly bracket on the right half of the case.

After some careful measurements, I came up with a couple of designs. I'm pretty sure of the general design of the face bracket, but still working on ideas for the right side. I printed out a full scale drawing of the face bracket and glued it to a piece of 3/8" plywood. Using a Roto-Zip, drill and sand paper I followed the lines on the drawing.

Looking at the wood bracket mounted to the motor and the frame, it almost looks ready to use. But a second look shows some flaws. The orientation of the face bolts is going to interfere with the chain, since there is only about 1-3/8" clearance between the face plate and the frame. I will need to rotate the bolt pattern so one of the bolt heads is between the loop of chain. The other probem is the verticle position of the motor shaft relative to the swingarm pivot. The motor needs to go about 1/4" higher so the chain can be vertically centered on the swing arm.

Another thing that is obvious is that wood is not the ideal choice for the actual bracket. The weight of the motor twists the wood like its made of rubber. Fortunately, the final version will be made from 3/8" aluminum plate.

While I was making a mess in the garage, I decided to to cut the bottom out of the gas tank. This frees up some space for mounting electric compents and saves some weight. After breaking a few bits on the RotoZip I switched to the Dremel using little cut-off discs. While effective, the Dremel was excruciatingly slow, but the end result was pretty clean. Cutting out the fuel tank was almost cathartic. It's like I was setting the bike free from slavery to big oil.

Run El Gixxer, be free!!