There are several ways to do it. I am assuming your kick start is still there.
1. Pull both plug wires off the plugs.
2. take out both plugs.
3. put both plugs back into the plug wire boots, make sure they are well seated. Be careful with the connection between the wire and the boot, they are fragile on these bikes. If it seems the wire is loose going into the boot, that may be the problem. Remember . . . THESE ARE FRAGILE
4. Turn the switch to "on", As you would normally start the engine
5. Lay each plug on the little deck where the plug hole is. If you have buddy there, this is best done in a darkened garage and with him holding the plug onto the deck. the outside of the metal part of the plug needs to be GROUNDED to a part of the bike. If you are outside in the bright sun, you may not see the spark, though if everything is operating correctly, you should be able to see it. But if you've never done this, a darker area is best.
6. Now, there are several ways to do this, so let's start with the "easiest" Hit the start button. (I am going to asume as you have a 74 that you have the e-start) At the tip of each plug you should see a strong bluish white spark. About one every second or so. If you don't have the starter, use the kick starter to turn the engine over. Check both sides and make sure if you have sparks coming at the tips. IF NOT, we move on to electrics. If you DO HAVE SPARKS we move on to fuel. (Again, make sure the bike is turned "on" when you are doing this!!)
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