Re: Skyhawk Frame up build
I haven't had any issues with my rag joint sprocket on my skyhawk frame. Then again, i use quality rims with thick spokes, so that may have something to do with the longevity.
The seat post is supposedly a standard size now. I think it's 38.2mm?
I recommend against getting a carb "upgrade". I wasted so much time and money looking for more power and speed, and ended up right where i started each time. Use the money for a good quality head and expansion pipe exhaust (not one of those cheap banana pipes).
Can't help on the derailleur or sprocket adapter. I use a single speed bmx freewheel (with a 48cc engine, and it has enough power to never require pedaling)
Never stop wrenching