These are the known mechanical and performance specifications for your 1948-1958 Royal Enfield 500 Twin.
Basic Specs

Engine
Displacement500cc
TypeOHV twin
Details500cc OHV twin
Max RPM
Compression
Bore/Stroke
Valves/Cylinder
Fueling
Ignition
Exhaust
Lubrication
Cooling
Chassis
Frame Type
Rake
Trail
Front Suspension
Front Travel
Rear Suspension
Rear Travel
Seat
Seat Height
Alt. Seat Height
Total Height
Total Length
Total Width
Ground Clearance
Wheelbase
Dry Weight
Wet Weight
Wheels & Brakes
Front Tire/Tyre
Rear Tire/Tyre
Front Brakes
Front Brake Diameter
Rear Brakes
Rear Brake Diameter
Wheels
Comments
Post-war Production: The first post-war twin cylinder in a swingarm frame with telescopic forks. It was simply called '500 Twin' and most non-engine parts were shared with the new Bullet. Its factory photograph is often mistakenly called 'Bullet' on various websites.[5]