Dunstall alloy barrels

Question Can anyone out there tell me the date Dunstall first produced the Alloy 810 barrels?

Hi I dont know the date but I bought a set in winter 1972
Bruce MacGregor

The website on Dunstalls lists 1971 as the first year for the 810.
But there is no picture, as proof, so be a little wary.

http://www.woodgate.org/dunstall/models.html

It also lists the cylinder as kite alloy, but that may just be a typo...

It's not listed in the 1969 Dunstall catalog, so it's fair to assume it wasn't available then. The catalog does list an alloy 750 cylinder for 650 Triumphs, but no Norton cylinders. The Feb '72 Issue of Motorcycle Mechanics has a test of a Commando fitted with the 810 kit, so 1971 looks pretty likely.

Ken

Do 650,750, and 850 Norton twins all have the same cylinder base gasket ?

Thanks for the replies guys, that could be the answer to both your and my eligibility crisis acoltrel? pretty sure the bolt pattern is the same but the crank mouth has some extra clearance machined in to clear the barrel spigot of the bigger bore of the 850, by the way I fired her up on the rollers today, first ran it up with the plugs removed till the oil pressure registered, then put the plugs in and she started first drop of the clutch! Sounds awesome! Just ran it enough to warm things up and make sure the oil was returning to tank, oil pressure was up at the limit of my dodgy 100 psi gage that at rest reads 20 psi, too early to tell if the eight start worm drive gears will be a good thing or not.
Now I am just hanging out for a trackday, Heath cote park has a tune day on the sixth of Jan but I am not so sure the dragstrip is the right place to break in the new motor, the next trackday at broadford is 13th of jan so i will book that one in, then there is the issue of competition licence, club fees and eligibility. The fun begins!