have a question about 1978 gs 750 suzuki

[TRISHNHARLEY@HOTMAIL.COM]

I have this bike and I need to know if anyone can tell me how to set the timing on it.I would also like to know do I have to remove the points to set the timing for the crank or not? CAN ANYONE HELP?

[tkent02]

Set the point gap first, use a dwell meter if you have it. Then turn the point plate until the timing mark lines up using a timing light at low RPM, there is a second set of marks that line up at full advance, somewhere around 3,000 RPM. One point plate moves one set of points, the other plate moves both sets. You can download a free Suzuki service manual for that model, check bikecliff's website.

[Go Mifune]

this was posted by earl earlfor a while back.
I followed these instructions with good results.
Here's the proceedure for timing the 750. The points are located under the round cover on the right end of the crankcase/crankshaft.

The round 6" plate that both sets of points are mounted on (breaker plate) is held in place by three screws located at 12, 4 and 8 oclock.
Loosen the 3 screws on the breaker plate. Note that the screw at 12 oclock is in a slot. Rotate the breaker plate until the 12 oclock screw is centered in the slot. Tighten the three screws.

We will replace the left side set of points first (located at 9 oclock position) These are the points for cylinders 1 and 4.

Take a 19 mm wrench and rotate crankshaft until points are at widest gap. Unscrew hold down screw on pointset and remove points. Note the white wire that goes to the pointset and the placement of the insulator. The insulator must be correct or the points will be grounded out and will not work. Put the new points onto the breaker plate, set the gap to 14 thousandths, and lightly tighten the hold down screw. Install white wire.
Rotate crankshaft once again with 19mm wrench until points are at widest gap. Check that widest gap remains at 14 thousandths. Adjust and retighten holddown screw if needed.

Rotate crankshaft until rightside points are at widest gap (for cylinders 2 and 3) Remove old points and install new points and set gap at 14 thousandths. Note insulators on black wire installation. Rotate crankshaft with 19 mm wrench again stopping at widest gap. Recheck gap as you did with the left pointset. Adjust and retighten hold down screw on points if needed.

THE ABOVE COVERS SETTING THE POINTS GAPS




Next is the timing:

Timing for cylinders 1 and 4 (the left set of points)....................
With 19 mm wrench, rotate crankshaft while looking through the timing window and align the mark that looks like F1| with the timing mark on the engine case.
(the line following F1 is the mark (|)

note: some bikes will have a stationary timing mark on the engine case and some will have a mark on a stationary timing plate that can be seen through the timing window)

Connect a continuity lights wire lead/clip to the white wire clip on the left pointset. Clamp continuity light probe tip to ground on the bike or battery negative terminal.

Turn ignition switch to on (do not attempt to start bike, just switch ignition to on)

The continuity light should be on.

Loosen the three screws on the breaker plate located at 12, 4 and 8 oclock. Rotate breaker plate until continuity light just flickers out.
Retighten the 12, 4, and 8 oclock screws on the breaker plate.

Unclip continuity lead from left pointset.



For the Right pointset
Rotate crankshaft with wrench until you see the timing mark F2| become aligned with the stationary timing mark on the engine case.
Connect continuity light lead to black wire on right pointset.
The ignition should be switched on and the continuity light should be on.

The right pointset is mounted to a breaker half plate.
You will see that you can loosen the mounting screws on this breaker half plate and this will allow you to move the right pointset. This will adjust the timing without changing the points gap. When you rotated the complete breaker plate for the left pointset to get the continuity light to flicker out, thats what you did. You adjusted the timing on cylinders 1 and 4 without changing the gap on their pointset.
Unfortunately, the whole breaker plate being rotated moves BOTH sets of points, so that is why you must set the left side first and that is why the right side is mounted on its own independent half breaker plate.
SOoooooo.... Loosen the breaker half plate on the right side and rotate as needed to cause the continuity light to just flicker out.
Tighten the half plate back down when satisfied with the adjustment.

Remove continuity light and HOPEFULLY, start bike.



Earl

[TRISHNHARLEY@HOTMAIL.COM]

to tkeny02 & Go Mifune

I just wanted to say thank you for all your help. This should save me a lot money, as I don't have to go to the bike shop to get this done now. We are in ontario and it costs anywhere from $60.00 - $100.00 per hour for a mechanic to work on a bike. As I have found though having a 1978 no one around here will even touch my bike. They say it is too old, and I should get a newer one...... SO AGAIN THANK'S SO MUCH FOR YOUR HELP... IT IS GREATLY APPRECIATED...:-D