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#6320
efr215
Participant

I do not have an exact answer for you, I am neither familiar with the model or how the valve gear is laid out but there is usually a sort of symmetry involved with 4-stroke valve timings.

In general valve events between makes do not vary all that much despite what the adherents to any particular marque would have you believe. When it comes down to it all 4-strokes go suck–squeeze–bang–fiss!

Wild valve timings will provide more power at the expense of tractability but really it is the whole valve train, subtle cam and follower profiles and good port design that make the real difference.

That said I would expect the timing for a road machine to be something like the following:

Inlet period 285°
Inlet opens 40° BTDC — 22%
Inlet closes 65° ABDC — 64%
Exhaust period 280°
Exhaust opens 70° BBDC — 39%
Exhaust closes 30° ATDC — 17%

Your machine will obviously not be exactly the same but this is a good starting point. If the above fairly representative angles are expressed as a percentage of the stroke, (180°), as indicated above then if you measure when the cams on your machine open and close it should be possible to apply these percentages to your timings. If still in doubt set the inlet opens and exhaust closes timings disposed about TDC as above and then check inlet closes and exhaust opens and see how they compare.

Do make a neat diagram to refer to and remember that these confounded 4-strokes do 720° to go round once — begorrah!