Turning a 502 into a 503

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Go Go Diablo
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Re: Turning a 502 into a 503

Post by Go Go Diablo » Tue Jan 31, 2012 11:07 pm

As mentioned earlier, the PTO shaft on the 191R motor is larger. I refer to it as a 30mm. Finding a Salsbury clutch with a 29mm bore is rare, so I take the clutches apart and have the bore machined out to fit the larger shaft.
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I use a 29mm bore on the clutch so when mounted, the clutch is about 3/8" to 1/2" away from the motor housing. A 30mm bore will let the clutch hit the bolts on the starter.
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Too many Diablos and parts to count.
Yamaha 600 SX

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Go Go Diablo
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Re: Turning a 502 into a 503

Post by Go Go Diablo » Thu Mar 01, 2012 9:36 pm

I guess the last thing to talk about is the wiring.

Obviously the wiring from a 502 to a 503 is different. Without a lot of typing, it would be difficult to explain all that is needed regarding the wiring changes. Each time I restore a 503, I run all new wires anyway. So if you need a wiring diagram, just give me a shout and I'll get you one.

The short answer about the wiring is that you need a new key switch. With this key switch, I also use a plug in harness. The harness protects the terminals on the back of the key switch from the bare steel wrench swinging around while doing things like changing spark plugs and such.
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I like using the battery terminal protectors too for the same reason.
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Wiring is needed to the Voltage Rectifier and the lights.
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Too many Diablos and parts to count.
Yamaha 600 SX

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Go Go Diablo
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Re: Turning a 502 into a 503

Post by Go Go Diablo » Thu Mar 01, 2012 9:40 pm

That's it! Make these changes and your electric start Diablo 503 is ready to roll!
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Bruce
Too many Diablos and parts to count.
Yamaha 600 SX

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