suggestions please

deacon

minor bike philosopher
Jan 15, 2008
8,117
3
0
north carolina
I had the 42cc chainsaw engine break the drive shaft so I junked it but, I am having second thoughts. the drive shaft has about an inch left sticking out of the case. Does anyone have any ideas how I can easily with a minimum of expertise. add a drive to it. I would be willing to go gear and sprocket since I have a scooter wheel complete with tire. sprocket and chain. I can use it as the friction drive if I figure out how to attach the front gear to it. The front sprocket has a 1/2" ID.. The drive shaft on the engine is 11mm smooth now. No threads no keyways nothing...

If you do have any ideas I would appreciate the help. Since I have written it off as junk anything is open to consideration. But I don't have a lot of skills.
 
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xPosTech

The Old Master Motorized Bicycle Builder
Oct 23, 2008
209
0
0
SETexas
It really depends on how hard it is but I think the easiest would be to grind a flat to accept about a 6 MM Allen head set screw. Use a roller drilled 11 MM and drill and tap for the 6 MM set screw.

Next (in difficulty) would be to drill the end for the 6 MM set screw, same roller. Next would be to skip the flat and drill all or most of the way through for a longer 6 or 8 MM cross bolt. Fourth would be to have it threaded.

Just my 2 ¢.

Ted
 

deacon

minor bike philosopher
Jan 15, 2008
8,117
3
0
north carolina
all suggestions are welcome.... I have been kicking around this tell me what you think.

the inside diameter of the sprocket is 1/2" it also has a hole straight through the opening I can install a pin in it.

The shaft is 11mm outside diameter..

Im thinking bronze 1/2" od bushing with a 3/8 id. I have a 7/16 drill bit. Approx 11mm and change.

I'm thinking drill the inside diameter of the bushing. Epoxy it into the sprocket and to the drive shaft so it doesn't move while I drill it.

Drill it all the way through and add a small nut and bolt as a pin or anything else you guys think might work. epoxy the pin as well as the other parts. Do you guys think it would hold together that way or am i spittin in the wind.
 

5-7HEAVEN

Well-Known Member
Aug 2, 2008
2,522
136
63
My suggestion is to weld the bushing onto the shaft, then drill and tap sprocket and bushing for setscrew(s).

The sprocket size might not be optimum. If you weld the bushing onto the shaft, you can always replace sprockets or pulleys.

More versatility.(^)
 

deacon

minor bike philosopher
Jan 15, 2008
8,117
3
0
north carolina
Well it is ugly as heck but I did it like this. I got a smaller steel tube, I cut it to length then cut the side and wrapped it around the shaft. Then I slipped the cog over it and welded all three pieces together. A little grinding and it seems to be okay. Most likely it will fly apart lol. When I start it.