I know a lot of you tune your own lumps, member Bob Whyman thought this little toy may help!Firstly you should disconnect the dizzy cap and low tension lead from the coil and set up a new live feed lamp as shown, you don’t need the ignition turned on or have to start the motor up to check the points. After you’ve fitted the disc & rotor into the dizzy you’re ready to start…
- Rotate the engine, by hand, until the lamp comes on – this shows the points are open.
- Tape a pointer to the side of the dizzy set at zero on the disc.
- Carry on rotating the engine until the lamp goes out and read the disc.
- The pointer should read 50 degrees (plus or minus 2 degrees) if the gap is set right; if not then the points will need to be re-set.
- Opening the points gap will increase the angle, and closing it will reduce the angle.
Once the gap is correctly set, remove all the gubbins and re-connect the dizzy as it was originally, and you’re ready to run. Brum-brum! Gurgle…gurgle….!
It lets you check the gap across the points as they open and close while the dizzy rotates; the handbook calls it the “dwell angle” and it should give the same result as setting the points with a feeler guage. All you need to make this Blue Peter engine tuner is a tube of glue, a spare rotor arm, a pair of scissors and some stiff card (you knew you kept those Christmas cards for something…).
