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R51/3 - can't kill the engine...

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Micha
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R51/3 - can't kill the engine...

Post by Micha »

Slightly embarrassing phenomenon: when I pull the key out of its place in the headlamp, the engine continues to work.
The magneto kill wire goes from its pole on the magneto to pole # 2 in the headlight's ignition switch plate.
As far as I know, this is the right connection. The key itself activates ok and turns on/off all other lights correctly, etc.
I need to pull one sparkplug cup off to still it :(

As always - your help much appreciated...
Michael Steinmann
R51/3 1952
Engine Nr. 529466

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schrader7032
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Re: R51/3 - can't kill the engine...

Post by schrader7032 »

The key is supposed to ground (or unground...I can't remember which) the coil and stop the engine when pulled. I've experienced this a little on my R69S. I suspect there's something wrong with the circuit board or key mechanism in the headlight shell. What I've been doing to kill the engine is whack open the throttle when I arrive home. This creates a situation where the gas fumes into the engine are greatly reduced...the bike usually stops.
Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2
Fast. Neat. Average. Friendly. Good. Good.

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wa1nca
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Re: R51/3 - can't kill the engine...

Post by wa1nca »

Yes the wire from the magneto goes to #2 on the switch board and when the key is out it shorts out the coil
/points/condensor to kill the engine
If you look at the movable contact on the switch board,it has a top contact that when the key is down connects battery positive to lights ect
Their is another contact point on the bottom of the movable contact ( which is hard to see) that connects #2 wire to ground when the key is removed killing the spark
If you push down on the movable contact with the key out it should kill the engine, clean this and it should work
Tommy
Tommy Byrnes
54 R51/3, 55 R50/Velorex 560 sidecar, 64 R27, 68 R69US, 75 R75/6
Ashfield, Ma
USA

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