Ok 3 types of jet blocks the four hole type matches the body with four holes, The jet block with about 1/4 inch hole in the front matches a 1/4 inch hole in the body at the front and the body has a extra lump in the front. The Norton jet block as fitted to some Nortons and specific to Norton has no holes on the body and the jet block at the front has the 2 1/8 inch holes and the flat recess as shown in the photo of this thread. Regards John
Jeromy I’ve re set the cams anyway, I manage to get it to run briefly but the mag decided it wanted to pack up so I’m still finding somewhere to refurbish mine.
John I know I now know what jet block I need, it’s just finding one
Well I got hold of another correct AG4 mag which has been rebuilt, I’ve fitted it and set the timing. I also fitted the Norton carb with the 206R jet block to se what’s it’s like and to be honest the engine starts and runs very well, also there’s no fuel spitting out, please note, I Havant cut or drilled the carb body. Air mixture adjustment is also working.
The only thing ive got to try and do is to stop the mag from slipping forward? I think the way Norton mags are mounted is a crap idea,
Lex says that the 'R' jet block works in an unmodified Norton body but I must admit that I can't for the life of me work out how. The block is a push fit in the mixing chamber and the pilot air inlet is completely obscured...Where does it draw pilot air from ?
I don’t know Rik, the air ports or pilot feed holes on the back of the jet block do seem to line up, Maybe it’s still some how getting air through the front, I’ve also got the Norton filter fitted.
Well I got hold of another correct AG4 mag which has been rebuilt, I’ve fitted it and set the timing. I also fitted the Norton carb with the 206R jet block to se what’s it’s like and to be honest the engine starts and runs very well, also there’s no fuel spitting out, please note, I Havant cut or drilled the carb body. Air mixture adjustment is also working.
The only thing ive got to try and do is to stop the mag from slipping forward? I think the way Norton mags are mounted is a crap idea,
Thanks, Barry
I am surprised - I have never had a problem with a Norton mag slipping forward or backward for that matter. Four screw fixings to the plate and a bolt and locking threaded screw between the engine / gearbox plates works fine - well for me anyway.
If anything moves that shouldn't then it is usually the gearbox especially if the tension adjustment bolt is broken through the gearbox top bolt and I have had that happen once requiring a piece of wood to be hacked out of a fence and wedged between the gearbox and engine / gearbox plates to get me home.
If the magneto is slipping forward on its platform then surely the mag chain is set too tight?
