ignition/timing help gs750

[Guest]

if i'm having problems tuning my bike could the cause of it be from the timing not set right? the PO installed a dyna s ignition system and I was wondering if its possible he messed up the timing? what would the timing be for that on a 1977 gs750?

[tom203]

if i'm having problems tuning my bike could the cause of it be from the timing not set right? the PO installed a dyna s ignition system and I was wondering if its possible he messed up the timing? what would the timing be for that on a 1977 gs750?

What "problems" are you having? Do all spark plugs seem to be firing ?
Do you have access to timing light and can you read the timing marks on crank end?

[1977jonc]

It bogs between 0-1/4 throttle. Spark plugs are firing. Havent opened the ignition housing yet

[tom203]

It bogs between 0-1/4 throttle. Spark plugs are firing. Havent opened the ignition housing yet

Good old Basscliff has this manual - has timing specs towards end

http://www.mtsac.edu/%7Ecliff/storage/gs/GS750E_1978_Owners_Manual.pdf

edit: on second thought,call dyna and see what they say about timing.

[1977jonc]

ok thank you for the info.

[whiterabbitt]

Or rig up a simple test light, the smaller the bulb the better. Hook one side to ground(engine case) and the other to the connector/terminal of the side you are trying to adjust, lets say 1-4. Slowly turn the engine over clockwise with a wrench until you get the 1-4 F mark lined up with the mark on the timing plate. Loosen the 3 screws holding the ignition plate and rotate it so that the light just comes on, tighten screws. Rotate the engine a couple times to verify that the light comes on when the two marks line up, readjust if necessary, fine adjustment can be made by moving the pickup(the black curved thing that the wire goes to). Then proceed to the other side and set it so the 2-3 F mark lines up with the mark on the timing plate, this time making adjustments by moving the pickup. Rotate the engine a couple times to verify that the light comes on when the marks line up.
This will give you a static timing setting and the bike should run decently. Further and more precise adjustment will require a timing light. Use the F mark up to 1500rpm and use the mark to the right of the F mark above 2500 rpm for advanced timing.

Note: sometimes you will have to move the pickups so that you can rotate the plate far enough to bring both into adjustment. I had to set one pickup at the max to one side to be able to bring both sides into time. I don't remember which way or which side now but I thought the info might be useful to keep in mind.