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Folks,
Just been measuring my 1977 sport valve timing. The previous owner informed me it has a reground cam by NLM but he didn't know what spec it had been ground to. When measuring at 1.0mm valve clearance my inlet opens spot on at 28 degrees but closes at 63 degrees instead of 55, the exhaust is also spot on opening at 57 degrees but closing at 42 degrees instead of 25. Anyone had a cam reground and had similar figures?. I should add that the bike runs great, I'm just curious.
Thanks,
Alan.

Looks like it is an L-5 regrind that has the opening intake event timed like an S cam....

The most important events are when the intake closes and then when the exhaust opens...

You might have more power available if you play with the timing,,, or maybe not...

Robert

NLM only offer one regrind and that's the L5.

Cam timing affects where peak torque will be generated. NLM have told me in the past they just use the stock timing marks, which might be why they don't like the 2+2 profile.

Paul,et al,
I remember talking to NLM and they said they use the stock timing mark. They also said it's the only slot which is intersected exactly in the middle by the edge of a tooth, however, there are two teeth which could possibly comply with this. My old gear had a small mark by one of the grooves, I took this to be the stock timing mark and, although it wasn't the same groove as I was using, assembled it as such. The bike ran pretty well, but was rich with black plugs and din't have that same top end rush. I then dug out the timing wheel, and checked the valve timing using the original old gear position, hey presto, I had it right to begin with. So, the wrong position (for my bike) looked like the edge of the tooth was slightly too far to the right (looking from the cir clip side) to be in the centre of the slot, the tooth I used to get my timing correct was 4 teeth to the right and looked to intersect exactly. Hope this makes sense?. The plugs are now a very nice colour, pale beige centre electrode with the outer ring slightly dark colour almost black
I've now set my valve clearances to .006"
I love my Morini!.
Alan.

Morini equipped the bottom pulley with multiple keyways to allow for accurate cam timing to be set at the factory, or if a cam was relpaced.

Once set new marks should be made.