Trying to get it closer to looking done for the parade next week. It’ll just be on a trailer, so don’t need to worry about making it safe for a 4 year old to ride just yet (chain-guards, brakes, etc). So knocking out a few key aesthetic details/components…
Got a pretty big hurdle out of the way, which was routing the exhaust. The real Batpod, they hid to the exhaust by running it inside the frame to further the illusion that there is no gas motor in it. But this option was easier for them since they used a 4-stroke. I’m using a 2-stroke motor, and the expansion chamber is both required, and can’t be highly modified (at least not easily). So, I took the whole Batpod and the pipe that came with the motor to a friend, Fothergill (thanks again!), who has a good welder, and who himself is a much better welder than me. We modified it to go straight down, back, then angle out. It actually goes between the frame rails under the motor, so a little hard to see what’s going on, but that’s really the point, to have it as hidden as possible.
I also began work on the foot rests. Here’s the left side one. Using thin plywood, then fiberglass cloth over that, all backed by steel. Doing them in fiberglass to save weight, and they are easier to make all the slotted holes in like the real ones have.
I put the rear hub in it’s sleeve, in the rear frame tube, then cut that rear chain to length, and did a little test of the rear jackshaft-to-chain-to-rear hub. The chain running through the top tube, around the sprocket, and back through the bottom tube to the rear sprocket, with no rubbing inside there is awesome if not shocking, haha. The action is nice and smooth, very low friction.
Did some work on the drivetrain, trying to get closer to testing the motor, chains, sprockets, jackshafts, bearings, gearing, rear hub, etc. I made the front jackshaft, which has the big sprocket driven by the motor, then turns a small sprocket which then drives the sprocket on the rear jackshaft. This front jackshaft is made from a 3/4 bolt, which I had to grind a groove into for the keyway, for the sprocket keys. It’s ready to install.
I also made one final spacer (black UHMW) for the rear hub, which helps holds the wheel bearing/race together. I greased the bearing, and assembled the rear hub. It’s finally ready for install into the rear frame tube, so I can cut that rear chain to length etc.
I’ve had the classic Brakes Blues. I like making stuff move, not making it stop! Anyways, got a few things done, or at least planned.
First off, I needed a way to keep the rear hub and sprocket centered inside the rear frame tube, so I had to go to the big guns. A friend of mine, Keith, from way back in school is now a machinist. I got a wheel bearing to go around the 1″ shaft of the hub, and had him make me a nylon sleeve to match the outside of the bearing race, and the inside of the rear frame tube (thanks Keith!!). Here it is sorta layed out:
Next I am workin on the rear brakes. The wheel is so small, it’s hard to get a caliper inside of it. So I’m making a sort of hub to go on the other side of the wheel, which will hold the brake rotor. In this pic, a bike sprocket is showing where the brake rotor will be.
Gonna weld the big washers to the piece of tube, have it bolt to the wheel with the same bolts that hold the hub on the other side.
I made the mount to support the front of the engine cover so it’s in its final position. I layed some wax paper on the engine cover, put body filler on the bottom of the front half of the seat, and smashed it on to create the curve of the engine cover.
I got a little tired of the raw steel look of the frame, so I sanded the light surface rust and sprayed a coat of primer to see what areas need some clean up before paint. And just cause it looks cool.
I cut the access hole in the back of the frame, to where I can put the chain on the rear sprocket. The hub ended up the perfect length, with the sprocket centered as seen, and the wheel also centered on the frame. Need to make a few wheel spacers and get the bearings installed where the hub goes into the frame tube.
Next up I need to cut the chain to length to go around those sprockets.