I have Inherited several "Old British" bikes (1953 Velocette MAC, 1952 Vincent Comet and his Speedway JAP's) from my Father who passed away from Mesothelioma in late 2017.
I have Finally gotten around to picking up the Last item He had "hidden away from Mum" (in various mate's back sheds....I bet He wasn't the First and won't be the last to do that), Namely his old "Speedway Stock-bike" that he used to ride before I was born. Apparently it is Based around a BSA Goldstar of some sort, his Last few weeks were a Little Hazy as is the Memory of the Guys he Raced against...who I am in regular contact with.
What I do know for sure is that it has a Engine number that Starts as ZB33-5***, it doesn't have a GS or A behind the 33. I think I recall him saying it had Goldstar cams in the motor.
It was run on "BP J.B." fuel and the Only information I have found comes from Phil IRVINE's book "Tuning for Speed". To make it, use 60% Methanol, 20% 115/145 AvGas and 20% Benzole....if I have the formula correct? Carby is a Amal TT?
It was last ridden in the late 60's or early 70's and hasn't been started since. Oddly enough it tyres still will hold pressure after all that time when I pumped them up.
It will probably become a Display piece for the WA Classic Speedway Association (of which I am a Member) in the near future in it's current "Patina" or with enough work put into it to make it look "Ruff'n'Ready" as they were "Raced in the Day". He didn't want me to go "Overboard" with any Restoration work to it.
As I've said Dad passed away a bit over 12 months ago, so this is about as much as I know about it and was Hoping that the Experts her might fill in any Blanks I have. Cheers Tony
Edit: 2 Pictures attached
hi
according to the info in machine dating engine is 1950 B33 500cc, i am unsure of frame as its a rigid type i am sure somebody else will let us have more information.
cheers
Frame looks like early B series to me. So, appropriate for this engine.