Re: frame wobble
Wobble and out of alignment are not the same thing. I'd like some clarification about what the OP is asking. If the frame is flexing or "wobbling" something is very wrong. It could be there is a broken weld at a critical point.
The problem might also be in the wheels. If one or both are out of true then a wobble could result. Even the cheapest department store bikes shouldn't wobble, even with an engine installed.
I think we're looking at a potentially serious problem and certainly a safety issue. My advice would be not to ride the bike until the source of the problem has been found and fixed. Examine the frame carefully for any sign of a broken weld or frame tube. Elevate the bike and spin the wheels to check them for concentricity and lateral alignment. Check bearings and axle nuts and handlebar attachment.
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