New Idea For Attaching Rim-Pulley To Bike Wheel

I was at the hardware store yesterday and came across these small plastic clips used in electrical applications to hold wire/cable in place. They are referred to as "cable P-clamps" in the hardware store. They come in a number of sizes. It got me thinking that they could also attach to the spokes of my bike wheel to hold my driven rim-pulley to the wheel. So I bought nine of the smallest at $.06 each, along with some small machine screws and nylon lock nuts. Total of $1.74 with tax. If this works, it'll be much easier than cutting slits in screws as I was doing previuosly. Furthermore, this set-up should be more forgiving. If something is going to break, my hope is that it'll be a P-clamp rather than a spoke. Another benefit is that since I'm using smaller machine screws, there is less chance of the screw heads interferring with the belt.  One downside is that these will add a little thickness, and I don't have much room, the tolerances are already pretty close.

I began swapping out the slotted screws with the P-clamps. There were only three that I'd made so it didn't take long. But after putting four P-clamps on (enough to hold the rim-pulley for evaluation), I found that they added too much thickness. This made the rim-pulley come in contact with the bike frame. Not enough to bind it, but enough to scrape and make noise. So I removed the rim-pulley and clamped it in the vise, closing the jaws to squeeze the outer edges of the rim-pulley together. I repeated this process all the way around the rim-pulley. It was enough to narrow the rim-pulley to clear the bike frame.  This is good news!

Here's how it looked when it was reattached using the P-clamps. I like how it turned out. You can see that the P-clamp is a little bigger than the spoke, but once I put all nine on, there was no play, the connection was tight.  So at this point I'm abandoning the slotted screw idea.

Now I need a Harbor Freight 15-20% off coupon to go get an engine and for the engine to be on sale at the same time. Once I do, I'm considering mounting the engine on the frame of the bike instead of a rack mount. I'll explore using the side mounts on the engine, attached to a plate, attached to the frame using some U-bolts or muffler clamps. My biggest concern with this idea is engine/pulley alignment. By the time I get it aligned with the driven rim-pulley, it may be hanging out too far to the right for me to pedal the bike.