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 Posted: 06-03-2019 05:31 pm
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Esprit2

 

Joined: 05-01-2005
Location: Minneapolis, Minnesota USA
Posts: 512
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cjwilson,
Draw in the imaginary centerline between the pulleys, and that photo pretty much confirms that, "IF" you wish to preserve the Original JH 115° IN / 115° EX emissions timing, then...
1) The intake pulley is correct, and...
2) The exhaust pulley is off by one tooth, counter-clockwise (retard).

The 115° EX 'emissions' timing advanced the exhaust cam 5° to start with, and each whole tooth increment equals 18° crankshaft degrees; so your exhaust cam is currently retarded 18° - advanced 5° = 13° retarded compared to the design-correct 110° IN / 110° EX.

"IF" you would like to take the opportunity to pick-up a little free horsepower, then re-time both cams to the design-correct 110° IN / 110° EX. As mentioned in post #3, that will require removing both pulleys, flipping them over, front-to-back, and re-installing them. A minor task.

Then follow-up by re-timing the ignition's static advance to 12°-14° BTDC, and re-tuning the carbs for best running (richer) instead of emissions lean (too lean).

Regards,
Tim Engel
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Attachment: cjwilson - Cam Timing - Cam Timing Mark, Wide - Notes, 95kb.jpg (Downloaded 105 times)

Last edited on 06-03-2019 11:13 pm by Esprit2