Re: motorized road bike build
I have to agree with Max Power that the rims and tires would be one of the biggest issues on a road bike. Another factor to consider is what material the frame is made from and tube diameter and thickness. These engines tend to vibrate pretty much and thin wall aluminum, titanium or composite frames even when backed up can get damaged.
Since they have thin tires they usually have less clearance between the rim and frame and there can be chain clearance issues that could also cause damage.