Britbike forum Forums British Motorcycle specific Brands Bsa bulletin board B44 Exhaust

How does the exhaust seal into the head on a B44 (1967)? Don't get me wrong, I love the sound the thing makes but the lovely bangs and burps the exhaust makes on the overrun (glorious noise!) makes me think that it is sucking air in at the head. All I have is the finned clamp and a copper (ferrule / olive). Are you supposed to use some goo?

I use red RTV for the same reason

Chris

As Chris said, use a sealant for the joint. The bike didn't come with a finned clamp, or whatever sort of ferrule you've described (?), just a friction fit... and it didn't work all that well, different expansion rates, machining, etc.... Even a high temp sealer won't last all that long, but you should use it...the banging might sound glorious, but it probably isn't long term healthy.

You can use bathroom silicone sealant, silver or pink . The TR25W I think came with a finned clamp which I use on all my Unit Singles.

Silicone goop it is then, think I will use the high temp stuff though rather than the bathroom pink! other than looking good what exactly is the point of the finned clamp? I cannot see how it helps sealing other than butting up against the head, which is hardly gas tight!

It’s function is supposed to help remove heat away from the head (I downloaded a bulletin the other day showing this) however I have stopped using them on my A65, least this one but that was more for aesthetics. A carbon black pipe doesn’t look quite right with aluminium colour heat rings.

ok, thanks for that, a niggling question answered!

The finned ring hold the silicone in place longer, bi-annual replacement rather than annual. And it hides it too.

Gotcha though I must admit I will miss the burps and bangs! probably safer for the passing horses and pregnant women though.

PS. if you want to make the finned clamp match the carbon black down pipes. I found (on a different built) that High Temp engine paint was quite frankly useless at painting exhaust. Then I found some matt black paint in a rattle can that was made for barbeques …….. grabs on to clean ally just fine, hard as nails and lasts well.

You can generally get away with an exhaust that is a little loud, but if it bangs when you back off it is likely to attract the wrong attention. A friend at work rode his bike in one day, one of the very rare occasions. It was a chopperish V4 with shortish pipes, it was the loudest thing I've ever heard, extremely loud when nailed, so he took off from in front of work totally nailed till he got down the road to the lights near the police station where he backed off and it sounded like a gun fight. Then nailed it again across the intersection when he got a green, if the cops inside were on the phone they would have had to pause their conversation.