Engine numbers

[Grumpy Geezer]

 I am currently restoring a Super Rocket and have recently had the crankcases vapour blasted. I now have very clear numbers on the crankcase and would like some information regarding these numbers........as follows
DA10 R 4689...HC    I know its an engine number and I believe a 1962, but does HC mean High Compression or what?
Very much appreciate some info..

[bikerbob]

That number would indicate a 1961 engine. 1961 engines began DA10R-3001. 1962 engines began DA10R-5958 the HC does stand for high compression. You can check this out for yourself on the homepage for this site just click machine dating and follow the links.

[DerekAnderson8]

here it is

[JulianS]

The 1961 season bikes started in September 1960 and went through to August 1961.

[Grumpy Geezer]

THANKS EVERYONE>>>>>Exactly what I wanted to hear..