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Kevin E
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Thread Like Summary
Allan G, KevRasen, Nick H, NickL
Total Likes: 5
Original Post (Thread Starter)
by hacksaw
anyone have a boyer go bad on their brit twin? what is the symptoms ? how do you know its shot?
Liked Replies
by GrandPaul
If the bike is running better than it ever ran before, It's just about to blow itself apart.


The fact is, the best it ran BEFORE that was actually it's optimum condition. Now on this particular day when it's running "better", it's actually being overstressed beyond it's "natural" limits, and it's weak point will evidence itself.

So when you hear stories of blow-ups, and the owners say "it was running better than ever" (VERY common), I BELIEVE IT!
2 members like this
by Andy Higham
Andy Higham
"a B-B Rotor does not have separate magnets like an alternator rotor"

IT DOES! The rotor is a steel disc with two (three on triples) magnets attached by screws
1 member likes this
by John Healy
John Healy
The Boyer failure I had was proven conclusively by swapping in another box, with no other changes.

When the Rita was introduced on the 1979 Triumph T140 it was plagued with failure. We that's what we thought at first. Replace the box under warranty and the bike came back to life. "Bad" boxes were returned to Lucas, tested and then returned to the dealer. The box was good. It turned out that by swapping out the box it restablished the connections to the trigger plate in the timing cover. Box good, connections bad.

The original Rita had a 5 wire connector located in the area where it was exposed to water spray from the rear tire. The trigger connections would corrode. The solution happened when they moved the trigger plate connection up under the fuel tank.

"The Boyer failure I had was proven conclusively by swapping in another box, with no other changes." You did make a change! By disconnecting the old box, wih possible corroded connections, and connected up a new one, it is possible that the new conections cured the problem.
1 member likes this
by KC in S.B.
KC in S.B.
+1 Andy !! Seems like I have done everything possible wrong at some point. The above is one of them.
I also can go to alot of trouble to outdo myself. Once, convinced it was a great idea to “pre-oil” and bed stuff in a bit before actual 1st start, I rigged up a drive coupling to the primary crank spline, and let the motor turn awhile on electric drive. I was quite happy with the mechanical results, and NO it didn’t burn oil, still doesn’t. BUT, the electrical results took awhile to make sense. Ignition was not working, and had been working before work. Now what? From help here, I learned that my efforts fried the Boyer. Spinning the motor, switch on to see the OP light go out, with the plugs removed and wires hanging loose, killed the Boyer. Just one more lesson from the UofHardNox. Now I always have the plug wires in the circuit.
I have others but this one took the most effort to screw up!!!!!
1 member likes this
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