You are right, especially with classes now through 1990s and 2000s 2 strokes. I lined up on a pretty full gate last spring (open Next Gen). About 14 on the gate and I was more than double the age of virtually every rider at the gate. Had amazing battles all day with a 19 year old in his first MX race. Raced him 2 months later and he was far ahead by the 3rd turn. Young guys get fast much easier than 60 year olds.
I would think 1980 hubs are not backward compatible for a 1974??? Not a Maico guy. Dubya can build wheels with your hubs - a bit expensive. Also look up Vintco for some hard to find engine parts.
For your question -
https://www.facebook.com/JoeAbbatesCycleTherapy/ - He might have some good suggestions and is quite helpful.
Joe also has a Vintage Bike YouTube program on Wednesdays. MW850 would certainly have some ideas about what options there are.
I did my share of racing in 2021 and had plenty of other riders to race against. For me, one rider to battle, can make it a race.
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