ALTERNATORS

Al, have you tried filing some ridges across the rotor to act as teeth.........?

The voltage regulator type would be also useful, it could be the melting alternators are caused by modern voltage regulators instead of the Wassel sourcing policy. All my alternators are original or LAP UK made and no failures including the 1980's 3 phase one with a modern Mosfet based regulator.

Sorry to butt in here but what Al is looking for is not reasons why or how to prevent it, but details of people who have had the problem.

It would be useful to know details of charging system, how long you have been using it and anything else relevant.

I too am interested to hear.

Tony

but modern stators should stand up to modern regulators

Its a Wassell copy of a Lucas design last updated in the dying days of the Meriden Co-op when the 3 phase version was introduced. All had the voltage regulated by Zeners in some form even the 3 phase in a negatively wired bike. I would not define it as modern. I suspect there is a flaw in these Green Box alternators that makes them melt caused by a change in the production process to suit the supplier, but as modern regulators now shunt to regulate rather than produce heat this could also be a cause.

BUT-3 Phase is nothing to do with it nor is negative earth. 

Read what I posted again, I do not say all 3 phase alts are only negatively earthed bikes just a negatively earthed bike from the Tri Co-op. The negatively earthed T140 with 3 phase did come with a nifty tripe zener pack, when the Co op did the change I did the same to my Commando and went 3 phase negative earth with that triple Zener pack, the same 3 phase alternator is now running positive earth with Mosfet reg/rect.

I have a green potted one. It's been there for years and given no problems, so that is one negative.

It had Boyer Power Box for a long time. Now ot has one of yours!

Yes, I have helped quite a few people out with damaged stators.

Usually the melted ones are caused by poor clearance between rotor and stator or bad alignment.

More often than not, these are brand new Lucas (Wassel) stators that have recently been fitted.

Electrical issues are different - they usually result in the resin cracking out not melting.

It’s easy to spot the difference.

Green stators in green boxes are no longer, it is now back to the brown version but I am not sure they are LAP. Lucas now has a new owner who are shaking things up a bit.