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Fix Your Stuff

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Editing Step 7 —

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Fit a new spark plug

Switch the ignition on. You should see ~3A on the ammeter for about five seconds, before the igniter shuts off the current to the coil.

If you see 5A or more, your coil resistance is too low. You need to change the coil for a suitable 4 ohm one to avoid damaging the igniter box.

Start her up and go for a ride! All being well, the engine should pull cleanly and run well... If it feels fine, give it a good thrashing ;-)

If it kicks back or pinks, it's too advanced. If it pops & bangs on the overrun and lacks power, it's retarded.

After your ride, pull the spark plug and look carefully at the earth electrode. You're looking for the heat "telltale" mark to be close to the bend. Closer to the plug body = too advanced. Closer to the tip = too retarded. The plug shown in the picture is about right.

Unleaded fuel burns a little cooler than leaded fuel, which can result in plug fouling. If your plug doesn't stay nice and clean, try a grade or two hotter plug. My CSR runs on super unleaded and tends to foul the "correct" Champion N3 plug. It is much happier with a Champion N5.

You now have a spare Wipac points plate and advance/retard mechanism. These are almost impossible to find second-hand. Hopefully you won't need them again!

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