Adjusting the breakerpoints gap will change the timing, adjusting the timing (= moving the baseplate) will
not change the breakerpoints gap. You can experiment with this.
Take breaker 1+4 for an example. When I turn it counterclockwise, I increase it's maximum gap because what I do, is that I move its fiber heel closer to the cam and this causes the cam pushing the breakerpoint open
earlier and so timing will be advanced. By turning it clockwise I decrease it's maximum gap because what I now do, is moving it's fiber heel further away from the cam and so this will result in that the cam pushes the breakerpoint open
later so timing will be retarded.
Now take breakerpoint gap 2+3. It's placed in a mirrorlike position so now it's the opposite. When I turn it counterclockwise I in effect move it's fiber heel away from the cam and this will result in that the cam will push the breakerpoint open
later so timing will be retarded (a smaller maximum gap). When I turn it clockwise I in effect move it's fiber heel closer to the cam and this will result in that he cam will push the breakerpoint open
earlier so timing will be advanced (a wider maximum gap). At least on mine it does.
It's maybe a bit difficult to grasp, but if you find time to play with it, you'll understand. You can make a little drawing and keep it in your document compartment underneath the seat.
Now by adjusting the
baseplate, you move the
whole set
not changing the breakerpoints gaps in the process.
Moving the baseplate counterclockwise will effect in that the cam point will reach the fiber heels of both breakerpoints earlier and so results in advance.
Moving the baseplate
clockwise will mean the cam will reach the fiber heels of both breakerpoints later and so results in retard.
Now let's assume the bike has left the production line with the ignition perfectly set: breakerpoints gap perfect and timing spot on. The customer will ride his bike. What will change after a long, long time? Well,
not the position of the plate, that was and still is securily fastened by bolts. What
will change however a bit and after many, many miles is that the breakerpoints gap will change somewhat, either by wear of their fiber heels or by the points getting burnt in somewhat. And we know - read the above - that any change in breakerpoints gap will effect the timing. So if you replace the breakerpoints by new, the only thing to do, is to mount them in the same position as their predecessors were. It is very unlikely that the position of the baseplate has changed as it has been securily fastened from the start and so there's no reason why you couldn't do this by using the strobe and aim for a correct timing. If the new breakers are identical with their predecessors, automatically their gaps will be within spec.
Now what many do, after reading a manual, is that they change the position of the baseplate. Little do they realise that their manual describes a total operation as if the bike has been in parts. Unfortunately this means that these owners have to go the full route that the manufacturer had to do: first setting the gaps, than the timing.
You are in that process now. Here's a tip. If you're satisfied with the timing, take a box cutter and make a carf from the baseplate to the case so that, whenever you're lost, you'll have a reference to where to start. Don't worry the carf will only be seen when you look for it.
I realise all the above is a bit much, but when you have the parts in your hand or look at them and close your eyes every now and then, you will understand.
Two Tired has decribed what play there can be between the plate and the case and what to do about it. I have never learned from him however whether his plate was the genuine Honda part or an imitation. Mine is OEM and I do not have that play. But that's just me. Others may chime in with their experience.
Another tip: to reduce the eventual wear of the fibers heel to practically zero, make sure the little felt is lubed. A bit of ceramic grease on the cam and you'll be fine.
Here's a little reminder.
Moving breaker 1+4 counterclockwise will increase maximum gap (decrease dwell) and advance 1+4 timing.
Moving breaker 1+4 clockwise will decrease its maximum gap (= increase dwell) and retard 1+4 timing.
Moving breaker 2+3 counterclockwise will decrease its maximum gap (increase dwell) and retard 2+3. Moving breaker 2+3 clockwise will increase its maximum gap (= decrease dwell) and advance 2+3 timing.
Moving baseplate counterclockwise will advance overall timing (no effect on breakerpoints gap).
Moving baseplate clockwise will retard overall timing (no effect on breakerpoints gap).
If your timing is way off, start by checking/adjusting the breakerpoints gap and then set the timing the static way. From there you can take the strobe to check ignition at full advance and check the correct working of the advancer in the process.
