In my search for the simplest and cheapest conversions I would like to enter this project.
First of all the bike conversion was a piece of cake. It required two donor bikes. One 20" sissy bike $8 and the front from an old huffy I got for twenty bucks before I knew better.
The engine is a small homelite chain saw about 33ccs. Since it ran I paid $40 bucks for it and the guy thought he was doing me a real favor. You can get a brand new one for a hundred more or less. I have no brand loyalty.
So I removed the bar and cut away the plastic case until the complete drive side of the saw was open. Since I don't have dremel, I used my trusty saber saw. At this point I made a discovery that I hope is going to work out well. The clutch bell was held on by a nut. I did a little of this and that but came back to an old WW idea. I removed the bell leaving me about an inch of shaft between the nut threads and the clutch assembly. I removed the spring held outer parts of the clutch assembly, but left the clutch thing that is kind of a nut, in place.
I drilled a hole in the center of a 3/4" galvanized pipe cap. I slid it over the shaft and rested it against the clutch thing. I made a spacer from a half inch nut by rounding it off with a grinder so that it would fit inside the 3/4" water pipe. I added a lock washer and I personally used some jb weld as locktite. I DO NOT recommend this kind of lock but I had already tested it to be sure it would work before I added it. Locktite red should do the trick.
Then I built the engine mount:
1. The first piece was an angle brace like those on cheap storage racks for the shop. I bought it at home depot. It is the kind with all the pre drilled holes. Actually I had a piece left over from a previous build. The ending is cupped in it. It sits on one side of the brace and is pressed against the other.
2. You need a little platform the same size as the saw more or less. It gets attached to the above brace just to give it some stability. Here is where I got stupid. I bought a 2'x2' piece of 3/8" plywood and cut a piece with the saw. In hindsight I could have used the saw bar for this. It would have been close enough to the right size when welded to the angle iron. Oh well next time. You want to secure the platform to the angle brace with bolts.
3. If you can find a spot to run a bolt through the saw, through the brace, and though the platform this is a good thing. I was able to find a spot that allowed me to do that. It was a tail on the end of the chainsaw.
4. You also need an open upper part of the frame as well. I use an 90 degree shelf bracket on the rear end of the platform angle. I bolt one end of the shelf brace to the platform.. Then on the front I bolt a flat piece of steel. I use a mending strip from the hardware store or anything like that..... then a simple flat steel top rail to connect the two.
5. This is where you add the strapping hinge. I was fortunate enough to have the bolt that went through the chainsaw's tail the platform's angle brace, the wooden platform, and then the hinge. With that one bolr I tied it all together.
6. I made sure that it was what I wanted, then I removed the engine and welded all the joints. I'm such a novice welder that I left the bots in place as well. Welding made the frame much more rigid but bolts with locktite would have worked as well.
7. I welded a cross piece to the bike frame to receive the hinge. I also used a U Bolt around the seat post to hold it while I welded it and to give it more security. I bolted then welded the hinge to the cross brace and had the basic of the engine mount done.
8. I added a scissor hinge to the engine side to keep it from moving side to side.
9. I added a down rod to the shelf brace that goes across the tire for the suicide clutch and the spring and turnbuckle.
10. The throttle is something new but seems to work. I used an old shifter like usual but instead of stripping the engine I drilled a small hole through the handle of the saw. Ran the cable through the handle and the trigger. The shifter tightens the trigger. had to add a spring because I used a junk cable but I will buy a new cable soon and the spring wont be necessary.
11. The suicide clutch is no more than a lever that runs from the cross member of the mount to the front of the bike where it has a gizmo to lock it in the up position for starting and at stop signs.
12. I added two pipe clamps that plumbers use around the saw engine to secure it to the frame the top rail of the frame and the platform are also inside the pipe clamp. they in effect hold the engine in place.
It sounds complicated but it is the simplest build yet. This is a very simple build and can be done reasonably inexpensively.
The platform makes it possible to build even with the WW without stripping them down completely. It should also solve the problem I had with the WW crappy attachment points.
