Setting Advance by Static Timing

[frankfast]

In order to set static timing between 6 and 8 degrees I've had to rotate the points plate completely clockwise and even then have had to close the points gap slightly to achieve the proper timing. I know that the timing gear is where it should be. I've heard that others have had the same experience but it still doesn't seem right. By locating the timing gear one tooth off, would I expect to have more adjustment in the timing? I'm also wondering if the points cam is worn and could be causing this issue.

[ducwiz]

This very detailed instruction might help you: https://www.vintageveloce.com/p/setting-ignition-timing-advance-on_7.html?m=0
1 tooth off on the timing shaft's gear (Z=30) gives you + or - 12° i.e. 6° crankshaft angle.

Hans

[frankfast]

I'm very familiar with the procedure having to do it many times over years of messing with these singles. I've never had one where I've run out of room adjusting the timing. I guess the only solution is to rotate the timing gear for more movement on the points plate. Maybe at some point in the life of this bike things were altered.

[Duccout]

My Mototrans is the same; I can just about get it timed at the limit of the slots on the back plate.

Let us know how you get on moving the timing one tooth.

[frankfast]

The camshaft on my wide case 350 Scrambler was replaced by, I assume a cam on a 250 narrow case Scrambler, although I'm not completely sure. I believe wide case cams are interchangeable with narrow case cams. If that is the case, since static ignition timing for both bikes are different, how would that affect the static timing if at all? Rockers were also replaced.

[Jon Pegler]

While widecase cams and narrowcase cams are interchangeable, some Spanish cams have the keyway in a different position to Italian cams.
This is compensated for by having the lower bevel gear dots in a different position to the usual Italian marks.
I would never assume that it is just as simple as fitting the parts and lining up the dots.
Always check with a degree disc when assembling.
Also, the points back plates on 160 models are different to 250/350 models, so the adjusting slots may not be in exactly the same place and cover the same range of adjustments. Are you sure that you have the correct one?

Jon

[ducwiz]

While widecase cams and narrowcase cams are interchangeable, some Spanish cams have the keyway in a different position to Italian cams.
This is compensated for by having the lower bevel gear dots in a different position to the usual Italian marks.
I would never assume that it is just as simple as fitting the parts and lining up the dots.
Always check with a degree disc when assembling.

Once in the past somebody posted this photo:

bottom10.jpg

It explains the situation ...

Hans

[frankfast]

While widecase cams and narrowcase cams are interchangeable, some Spanish cams have the keyway in a different position to Italian cams.
This is compensated for by having the lower bevel gear dots in a different position to the usual Italian marks.
I would never assume that it is just as simple as fitting the parts and lining up the dots.
Always check with a degree disc when assembling.

Once in the past somebody posted this photo:

bottom10.jpg
It explains the situation ...

Hans

Since the bike ran well with the current setup, I'm more concerned with the ignition timing since the static timing for a narrow case 250 Scrambler and a wide case Scrambler are much different. How would the cam profiles affect ignition timing?