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  4. KSS, KTS Manuals
  5. F236/4R Mk. II OHC Instruction Book 1950
  6. The Ignition Timing

Remove the Contact-breaker Cover from the Magneto and rotate the Crankshaft with the Footstarter until the Contact-points are fully open.

Check the gap with the gauge on the Magneto Spanner, and if not correct reset the adjustable point to give the right clearance.

Fix a Timing Disc and Pointer (as described in the last section) after removing the Dynamo Belt-cover.

Open the Throttle and Air Controls fully.

Engage the Footstarter and rotate the Crankshaft until compression is felt in the Cylinder.

Release the Footstarter, and then remove the Sparking-plug.

Set the Piston to Top dead-centre and adjust the Pointer to zero on the Timing-disc. Advance the ignition control fully.

Move the Crankshaft BACK about 60º, and with the fingers separate the Contact-points. Place between the Points a small strip of Cigarette-paper or paper of similar thickness (.001 to .0015-in.)

Release the Points on to the paper.

Checking. Rotate the Crankshaft forward very slowly whilst main.. taining a light pull on the Cigarette-paper.

If the timing is correct, the grip of the Points on the paper will cease when the Crankshaft is 40º before top dead centre.

If not correct loosen the sprocket and re-set it.

Should no Timing-disc be available one can be made quite easily by marking out a card or metal disc in degrees by means of a Protractor.

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  • Velocette Documents
    • GTP Manuals
      • F40/5R GTP Instruction Book 1951
    • KSS, KTS Manuals
      • F236/4R Mk. II OHC Instruction Book 1950
      • F42/3R OHC Models 1925-1931 Instruction Book
    • MAC Manuals
      • F469/4R MAC Service Guide 1965
      • F466/2R MAC Owner's Handbook 1955
      • F50/7R MAC Rigid Frame Service Manual 1955
      • F50/4R Supplement
    • MOV and MAC
      • F131-3R Instruction Book 1937
    • MSS Manuals
      • F477 Owners Handbook 1954
    • Venom, Viper, MSS
      • F485/1R Owner's Handbook 1956
      • F484/9R Service Guide 1967
      • F484/11R Service Guide 1971
    • Valiant Manuals
      • F62-1R Service Manual