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Offline feliz

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timing question
« on: March 30, 2007, 04:20:18 PM »
My recently aquired K3 runs great but I don't think I can hold off getting into a "tune up" soon. I was wondering what the prefered method of setting the timing is, static or dynamic? I threw away my last timing light several years ago (25?) but will pick up another one if that's the way to go over the static method using a peice of paper I guess. My manual indictes that the points should start to open just when the mark gets to the F line and I'm assuming a peice of paper should fall out of the point contacts at that point. I assume I do the point gap first. Thanks for any insight.
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feliz

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Offline super pasty white guy

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Re: timing question
« Reply #1 on: March 30, 2007, 04:23:23 PM »
I believe that timing light is preferred, paper is for roadside repairs.

dave
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Offline Jonesy

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Re: timing question
« Reply #2 on: March 30, 2007, 04:25:09 PM »
I prefer to use a timing light, as even when I try to do it with the test light and stuff as described in teh manual, when I check it with the timing light it's never quite perfect.

A timing light is also useful for finding dead cylinders, too.
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slarty-bart-farst

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Re: timing question
« Reply #3 on: March 30, 2007, 04:31:38 PM »
Swith on your am radio and tune to no station, place near bike, turn on ignition, turn over with kicker then socket on crank end.  When you hear a pop on radio see the F mark on the engine aline. If it does not then adjust the back plate.  It's even possible with this method to set the F mark then turn back plate against engine rotatioin until you make the "pop" then screw down and recheck.
Graham
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Offline Gordon

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Re: timing question
« Reply #4 on: March 31, 2007, 06:59:25 AM »
Quote from: feliz on March 30, 2007, 04:20:18 PM
I assume I do the point gap first. Thanks for any insight.

Set the gap, then set the timing, then check the gap again, only to find out that adjusting the timing has screwed up the gap.  Re-adjust the gap, then realize this has screwed up the timing.  Repeat.

It's a labor of love. ::)
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Offline TwoTired

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Re: timing question
« Reply #5 on: March 31, 2007, 11:46:15 AM »
Quote from: Gordon on March 31, 2007, 06:59:25 AM
Quote from: feliz on March 30, 2007, 04:20:18 PM
I assume I do the point gap first. Thanks for any insight.

Set the gap, then set the timing, then check the gap again, only to find out that adjusting the timing has screwed up the gap.  Re-adjust the gap, then realize this has screwed up the timing.  Repeat.

It's a labor of love. ::)

Only for the physically challenged.  ::)
If you read the FAQ, a simple shim will make it pretty straightforward after the first excercise.

Cheers,
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Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline Gordon

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Re: timing question
« Reply #6 on: March 31, 2007, 12:01:32 PM »
Quote from: TwoTired on March 31, 2007, 11:46:15 AM
Only for the physically challenged.  ::)


Little confused by that remark.  Could you elaborate?
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Offline TwoTired

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Re: timing question
« Reply #7 on: March 31, 2007, 01:02:13 PM »
The gap is a radial adjustment, determined by the distance from the points "stationary" point contact to the center of the crankshaft.  If the point plate (on which the gap adjustment is made) moves in a radial manner, the gap changes.
The timing is a rotational adjustment.  This should be adjusted as a pure circumferential movement about the centerpoint of the crankshaft.

The two adjustments are NOT interactive provided the stationary contacts are not allowed to move on an axis you do not intend to adjust.

The physical challenge is to not move the stationary contact radially while moving it circumferentially.  This is what the plate shim ensures.

Cheers,
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Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

jmk

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Re: timing question
« Reply #8 on: March 31, 2007, 02:42:29 PM »
Another Questions:
The marks on my bike, a '71 750, have two lines which look like T '  F '  Which one should I use when I'm doing the point gap?  I'm assuming the F ', but I'm not sure.  Also, the gap continues to grow as I turn the crank, after both of these points.  This is ok right? I'm just confused because my shop manual says to take the measurement when they are fully open, but also says to line up the mark.  Which one is it?   Thanks,
-jm
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Offline TwoTired

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Re: timing question
« Reply #9 on: March 31, 2007, 03:59:05 PM »
The points adjustment has two phases for eacj point set.
Adjust gap
(Where the maximum gap exists on the highest place on the cam)

Adjust timing.
(That point on the cam where the points just begin to open)
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Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

warreng22

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Re: timing question
« Reply #10 on: June 08, 2007, 10:11:52 PM »
Quote from: TwoTired on March 31, 2007, 03:59:05 PM
The points adjustment has two phases for eacj point set.
Adjust gap
(Where the maximum gap exists on the highest place on the cam)

Adjust timing.
(That point on the cam where the points just begin to open)

You have got to be Kidding...  ::)

I cant believe the way the manuals (clymer) make it sound, no wonder I couldn't get my points set right.  :-[  The clymer manual makes it sound like you turn the crank until the F mark lines up, then gap 1-4, the turn over to the F mark for 2-3 and Gap that point... We should file a class-action lawsuit against clymer for being stupid.... ;D

Its a weird feeling, aggravation and relief at the same time. Aggravation that it was so simple, but yet I couldn't understand it, and relief that I finally know how to do it.

This should go into the FAQ's on timing. (it might be in there and maybe I just missed it...)

I was ready to take this bike to the shop to get it done.

Thanks Again Two Tired, this site couldn't do with-out you, and neither could I ;)
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