Stator Failure

I noticed the same problem on my 850's Lucas stator. I asked the question on this form and in the end I just cleaned the stator thoroughly, mixed up some epoxy resin and refilled the cracks. Still going strong 5 years later.

myjota said:

Araldite it and put it back on.

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Araldite ?

to quote Henry Norton

Failure looks like is down to the epoxy resin not the stator and right now I am wondering if the encapsulant does not have the required chemical resistance and has been affected by the warm to hottish oil. I am using a good quality semi-synthetic oil and this could be more aggressive than a straight mineral oil.?

if you have semi synthetic engine oil in your primary on a daytona you must also need a replacement crank oil seal , primary oil is seperate to engine oil

i have fitted Sparks / Wassell / LAP and all are prone to the same issues poor rotor clearance or damaged insulation normally accounts for premature failiure
check stator for any bad handling or transit damage prior to fitment minute cracks are sometimes visable and will open up when subjected to heat

Torontonian said:

Araldite ?

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Not sure I love the idea of an epoxy/araldite repair. Aside from the question of ever knowing you have removed all oil so that the repair gets good adhesion, a stator failure has the potential to create a major safety problem. IMHO better to replace with a new or used unit that has full physical integrity.

Re ; “Araldite it and put it back on.”

As I have found out epoxy will not stick to any oil residue on any component, you would really need to grind part affected away with a Dremel and clean with a solvent based cleaner before applying epoxy

“a stator failure has the potential to create a major safety problem. ”

Please, explain the “S” word as you’ve used it here.

It was common practice to repair stators with “araldite” expoxy when the wires failed/got ripped out. Cut away old rubbery potting material, solder on new wires and cover exposed windings with araldite.

concours said:

“a stator failure has the potential to create a major safety problem. ”

Please, explain the “S” word as you’ve used it here.

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"S" word - stator coming apart, jamming primary, causing primary to break and jam. Never happened to me but I did have a stator come apart - smelled like stale cigarette smoke - and fill the primary with a large mass of shredded material. I guess I could have put it all back together and continued on to see what would happen. . . . . Actually, I have started to wonder why potting the stator is an improvement over bare wires as on the original.

Bodger said:

. . . . . Actually, I have started to wonder why potting the stator is an improvement over bare wires as on the original.

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My thought too.
Most automotive alternator stators have lacquer coated bare wires.
I know auto alternators are external to the engine, and are air cooled, but any reasons why this would not work in a wet Norton primary?

I found an unpotted early stator on my '66 Matchless G80CS when I got it. Almost every coil wire was broken where vibration had caused the thin phenolic "coil forms" to disintegrate and then allow the copper wires to rub against the iron core. I made new coil forms out of PC board material and rewound it. I let it soak in polyurethane marine varnish a couple times until there was a build-up. The potting helps keep the coils from vibrating themselves to death. It was still working when I sold the bike years later.

kommando said:

TMS Motorcycles sell UK made alternatives made on Lucas tooling but not Lucas marked, LAP make them who used to be part of Lucas. It's a strange world when the pattern part is genuine and the genuine part is pattern.

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The same claims about the 'Lucas' tooling were also made about the 564 Rear Lamps, and the Stem indicators from the very same source.