Works fine on my 92bore with a bored out Gardiner a 42mm. I can tell you my 92 will drink twice that of your 86. You have to ensure the bore of the feed valve in big enough. And as I said run the fuel level higher than the traditional way of setting the float height.Learned a bit more about the Matchbox float chambers, which I had problems with earlier. On the about a dozen Manxes at Goodwood, most had Gardner float chambers, some had SU, no one used a Matchbox.
Learned that in the old days, riders was paid by AMAL for using their carbs. Had to use their float chambers too. So they got half a dozen float chambers, tested flow and used the best one.
Obviously a new made AMAL Matchbox is a close reproduction of the old one. Not usable on tracks with long straights.
Those tabs are not on the Reynolds / Norton factory drawing for the 1960 Manx frame. Have worked on 3 x 1960 bikes, 2 x 1959 and no tabs.Met an experienced Manx mechanic from Scotland in the pits at Goodwood. He answered to the question I asked in #8 in the thread. The tabs close to the steering head was fitted on 59 and 60 frames. Why no one knows. They were never used for anything. He kindly answered a lot of other questions ( and offered me a beer to).
Since tuesday I have two Victor Specials. Both running quite well. Might now be called a BSA twin owner.I've had 4 or 5 BSA 441s, they're great bikes.