autopsy of the bolens 31cc WW engine


minor bike philosopher
Jan 15, 2008
north carolina
I removed the engine from the Mtb to replace it with a smaller one till I can buy another 31cc. Here is what I know that happened.

The frame of the motor itself came apart. I had that happen almost from the first day in a different place. This time it was in a spot that allowed the drive wheel to bind as it ran. It did not run round but with a wobble. Since I had locktite on the drive wheel. Instead of unwinding the nut, it twisted off the drive shaft.

For want of a nail the horse was lost ect.

The case is broke the drive shaft is broken the fly wheel flew through the air. I got it but not the key. Next time I will definitely mount the engine to run in the direction it was designed. It would have tightened not loosened the wheel nut, if I had left it alone.
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