Sounds about right.
For others who are curious, the cam wheel is about 3” diameter at the chain pins, so one degree will be about .026” at the circumference.  There are about 52 pins in the chain between the two wheel centres, so .026" of stretch in the length of chain between crank and cam wheels would come from a shade over .010” wear per 5”/21 pins.

A degree or two may not be much in terms of cam timing on a low-revving lump.  If .010” will affect timing by 1 degree, then an old chain at factory recommended wear limit (1.8mm / .071”) will affect timing by 7 degrees – puts things into perspective.

Good point though when you add skim to the equation – the barrel skim and thinner gasket generate an extra 1.25mm on the straight side of the chain which will cause 2 degrees retardation of the cam, to which you then start adding wear.  

I originally considered slotting the cam wheel to dial in the cam in the Savage, but decided against it.  I may revisit that decision, slot the screw holes and re-drill a fresh dowel somewhere to give me about 3 degrees of advance, 2 degrees to compensate for the skim and maybe another one for initial chain wear.

I bet that gear is hard too – might have to grind through the surface with a Dremel before a drill can cut it.  Or, if I’m lucky I may be able to find about half a tooth of change by flipping the wheel – I’ll look into it at the weekend.

verslagen1 wrote on 04/26/08 at 10:31:00:
I thought about this and decided it was a case of 'if you're going to do the job, do it right'.

38 teeth on the wheel, so it's 9.47 degrees per tooth.  I wanted to make up for the 1.86 degrees of retard the barrel skim was going to give me.  

I used a Dremel to oval the screw holes and fitted a new cam stud 182 degrees out from the original.

I decided I was more interested in bottom end torque and good starting than top end, so didn’t want extra advance.  However, the 182 degrees ended up being 182.3, so it now has 0.45 degree advance over standard after the barrel skimming, half a degree for luck!

verslagen1 wrote on 04/26/08 at 13:07:37:
Surprisingly easy.  The holes went oval using a small stone - could tell it was fairly hard when I tried it with a round file.

I used the dremel to grind the top 20 thou off the gear face before I started drilling - drill then went in no problem, though it felt like it was snagging a little coming through the case hardening on the other side, but drilled fine. On the cam side it was only opening up the original hole from 5mm to 5.5, so that was no problem.

bump from the dustbin of history

I've been considering this head skim idea but as far as the timing retard/advance is concerned...it seems a fair amount of effort was put into calculating and drilling the cam sprocket. Wasn't EdL able to, around this same time, advance the timing 4* (more than needed for this skim) by simply ovaling the holes for the pickup?