1977 Berkshire?

[Rocket]

I have a 100 Berkshire, Sachs motor, the frame SN is 70393854, and the engine SN is 7828306,1001/6B.  This tells me that I have a 77 100, that I didn't think they ever produced.  From what I can get from brochures, 75 was the last year for the 100.  This bike has the 35 mm forks, 3 position shocks, big watermelon looking tank,(red)with the full length Penton decal, aluminum rims, enduro style rear fender w/tailight.  It also has the fiberglass number plate-exhaust pipe cover, leather tank strap, long tall seat and the rear hub is the cush hub w/big rubber bushings.  Has anyone ever seen anything like this before?
thanks
Rocket

 

[Mark Annan]

Got any pictures?
Mark

 

[400 Mint]

I owned and raced a 73 and a 74. I think the 74 was the first year for the smaller tanks.