Hi,
I'm currently trying to get a Simplex super LJ rear mech to work.
The LJ as I can see it has three springs. one for the jocky arm tension one for the parallelogram tension and one in the piviot pin assembly which controls the 'b' tension
It's the latter which is causing the problem. some previous owner has fiddled with this and it now doesn't have much tension or maybe it doesn't need that much. There's a little plate with two holes with a + - sign on it guess so you can vary the ammount of 'b' tension.
This little plate pops off and you can see the conical spring beneath. the LJ mounts to the frame hanger by being screwed in from behind.
So maybe its broken or maybe it isn't.
ANY advice would be welcome.
Cheers,
John