I have a 1949 plunger frame B33 with a 289 Amal carburetor and I'm trying to install an air filter using the elbow 65-9198 listed in the parts catalog. See the picture below.
The elbow, obtained from EBay, is an aluminum casting. I guess it was hopeful thinking to expect the brittle aluminum flange to squeeze onto the carburetor adapter when I tightened the clamping bolt. It didn't take much to break a chunk out the flange.
Has anyone had success with installing this elbow?
I was thinking my next try is to:
Grind off the bolt lugs,
Cut 3 additional slots in the flange 90 degrees apart
Extend the slots into the elbow body a little,
Grind some material from the inside of the elbow body
Clamp it on with a steel hose clamp around the circumference of the flange.
I am very interested in hearing any successful solutions that people have tried to get an air filter installed on a B33, with or without this elbow.
I fitted what Amal call a threaded cone filter (https://amalcarb.co.uk/monobloc-series/375-series/air-intakes/threaded-cone-filter-375-monobloc-289-pre-monobloc.html). It only just fits between the carb and the oil tank, but I have an M33 that doesn't have its original oil tank. The filter may fit your bike; Amal say it protrudes 77mm from the back of the carb.
If you get one, don't thread it on to the carb too tight or you'll never get it off again. Guess how I know...
Thanks Rog
The minimum distance from the rear tip of the threaded carburetor inlet to the front face of the oil tank is about 38mm.
Jim
I fitted a gauze filter to my 1950 B33. Just screws on in place of the standard intake.
Thanks Greenfield
Although it won't filter out dust, it will stop bigger chunks from going in the inlet, which is more than I have now.
Where did you get your gauze filter?
Jim
My original article was in August 2021 Star. It uses adaptor ring AM/289/110 and an air intake from a 389, AM/389/066B. I bonded the gauze filter onto the adaptor. At the time I got both parts from Hitchcocks. It ends up 1cm longer and 1cm wider than the original intake so should fit fine.
Thanks Greenfield
This may be a good option.
Jim
That's more of a flame trap than any sort of air filter, though I suppose it would keep errant bees out of the engine..