Author Topic: Setting the timing  (Read 274 times)

Offline smoothoperator

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Setting the timing
« on: June 27, 2022, 07:16:15 PM »
After 600 miles since rebuild I decided to check the timing, which I found was a little bit out. The bike is running well. Well it’s fair to say getting it spot on has had me baffled, you know the feeling that you have completely lost your marbles baffled. I simply couldn’t get both sets of points timed, I seem to have run out of range of adjustment. I decided to fit a new set of Tec points I found in my stash. I have now, after many hours, got pretty close, with the points gap set at 12 thou. Currently 2+3 is spot on, but 1+4 are slightly advanced. The main backplate is almost fully CCW and the 2+3 plate is fully CW. This should give me a bit of wiggle room.
Because it is close, and it has made me feel like a novice, I am loath to move it again until after Crich next Sunday which I am very keen to get to.
That said with the conflict between the Haynes and Honda manuals, could someone definitively tell me which way to turn the backplate to advance and retard 1+2, and which way to turn the 2+3 plate to advance and retard the 2+3 points.
Haynes manual says “Turning the back plate clockwise retards the ignition, and vice versa.”
Honda manual says ”Moving the plate to the right will advance the ignition timing and to the left retard the timing.” I am assuming that to the right means clockwise.
After all the adjustments I have made, you would think I would know, but my brain has turned to mush.
Steve
2017 Triumph Bonneville T100
1977 Honda 400 Four Restored April 2022

Offline McCabe-Thiele (Ted)

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Re: Setting the timing
« Reply #1 on: June 27, 2022, 07:47:55 PM »
I completely empathise with your situation Steve.
I had similar issues with setting up the sensors on my Dynatek ignition when I changed from the initial static timing to the dynamic timing. With points on a car the dwell angle was always the way to go rather than points gap.
If you look at the engine rotation moving the back plate in the opposite direction will advance the ignition timing.
Honda CB400 four super sport

Offline Bryanj

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Re: Setting the timing
« Reply #2 on: June 27, 2022, 08:20:03 PM »
Crank rotates clockwise looking at points so turnin plate clockwise retards, anticlockwise advances BUT the plates are never a good fit so moving the plates alters the gap and it becomes a juggling game to get both correct and gap should be 14 thou (0.35mm)or very close.
This has to be one of the extremely rare time the Haynes is correct and Honda wrong. Haynes are usualy very good firelighters!
« Last Edit: June 27, 2022, 08:21:51 PM by Bryanj »

Offline McCabe-Thiele (Ted)

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Re: Setting the timing
« Reply #3 on: June 27, 2022, 11:09:49 PM »
TDC crank marks by Macabe Thiele, on Flickr

Looking at the timing marks you need to move the marks from TDC to the F mark on 1-4 so you move the plate accordingly.
TBH as the marks are clockwise on the advance & retard I thought you need to move the back plate anti-clockwise to find the marks - don't listen to me as I got my plug leads in the wrong order  - listen to Braynj.

I just used the scale on my strobe light.
« Last Edit: June 27, 2022, 11:11:57 PM by McCabe-Thiele (Ted) »
Honda CB400 four super sport

Offline Oddjob

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Re: Setting the timing
« Reply #4 on: June 27, 2022, 11:37:50 PM »
Bryan is correct, anti clockwise advances it.
Don't play stupid with me, I'm better at it

Offline smoothoperator

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Re: Setting the timing
« Reply #5 on: June 28, 2022, 07:40:07 PM »
Thanks for the help people, this time around I set the timing fine and confirmed with strobe that the advance mechanism is also working as it should.
Steve
2017 Triumph Bonneville T100
1977 Honda 400 Four Restored April 2022

 

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