Topic: No more timing adjustment

[Rpghmi]

I was baselining things yesterday to see if I could make the 550 run better and found I couldn’t get the fire mark to line up. I ran out of adjustment. What’s causing that? It ran perfectly at this point for a couple minutes, better than it ever has then started chugging and making a lot of clacking noise. It was about 3/16” counter clockwise before I made the adjustment which would be farther off.

The picture shows where the “light” comes on.

[ekpent]

 Sometimes you need to juggle the point gap and the timing mark together at the same time when setting things up.

[69cb750]

I was baselining things yesterday to see if I could make the 550 run better and found I couldn’t get the fire mark to line up. I ran out of adjustment. What’s causing that? It ran perfectly at this point for a couple minutes, better than it ever has then started chugging and making a lot of clacking noise. It was about 3/16” counter clockwise before I made the adjustment which would be farther off.

Points fiber base worn out, replace points, sand advancer with #400, grease lightly.

[Deltarider]

http://www.sohc.co.uk/index.php?topic=22883.msg205349#msg205349

[PeWe]

The advancer springs are too sloppy, advance happen way too early and it will not help to set the plate at max retarded position as your photo show.

Cut each spring 1/2 wound and shape (bend) the cut end so it look like a hook as it did before.

When this is done you can set F correct at idle and see how case mark lines up at full advance at a proper rpm.
On CB750 around 2600-2700
(Both my CB750 have this mod)

CB5x0 later, maybe closer to 3000rpm if I remember Hondaman's posts.

[rotortiller]

[ Sometimes you need to juggle the point gap and the timing mark together at the same time when setting things up.
/quote]

+1

[Spanner 1]

Before you start on timing/ points gap adjustment, first set the points plate ( three screws ) to 1/2 way on its adjustment and the sub plate to 1/2 way on it's adjustment. Then set the point gap to 14 thou. with the points cam turned 90 deg. past the 1-4 'F 'mark .  Repeat for 2-3, again 90deg. past the 2-3 'F' mark. Then rotate the points plate for firing at the 1-4 'F' mark. snug up the 3 screws. Then turn the sub plate to achieve firing at the 2-3'F' mark. Done.

[mattsz]

Before you start on timing/ points gap adjustment, first set the points plate ( three screws ) to 1/2 way on its adjustment and the sub plate to 1/2 way on it's adjustment. Then set the point gap to 14 thou. with the points cam turned 90 deg. past the 1-4 'F 'mark .  Repeat for 2-3, again 90deg. past the 2-3 'F' mark. Then rotate the points plate for firing at the 1-4 'F' mark. snug up the 3 screws. Then turn the sub plate to achieve firing at the 2-3'F' mark. Done.

All the printed instructions I've seen for setting points gaps are vague: turn the engine until the points "are fully open" (Haynes), or in the case of the Honda manual, rotate the crankshaft clockwise at the special nut and check the maximum gap.

Information about exactly where the point of maximum gap occurs in the crankshaft rotation is conspicuously absent.  Maybe close is good enough?  But this is the first time I've seen anyone state a specific number...