How do I know I'm gettin spark?

74 cb 750

my first 74 cb 750 (beautiful monster)
On my spark plugs or if I should change the spark plug cables cause they're a bit loose...thanks!
 
Well if it runs well and all four pipes get equally hot that's the easiest way to tell. If not, pull the plug out, plug the wire onto it and then hold the wire with a pair of rubber handled pliers while you turn it over. If you get arc it's good...could be weak but you're gettng spark. If not, take the plug out of the wire. Now hold te end of the wire near the frame or motor...somewhere where it can ground. Turn it over and see if the end of the wire near the plug boot arcs to the ground. If not, it's either the wire or the coil. Check all wires and connections to the condenser...just troubleshoot everything before you decide bad coil. It could also be severely out of time. Set the points and time it first and foremost. A clymer or factory service manual is your friend. You can find them on this site. Good luck!
 
Re: How to know that I'm gettin spark?

hey thanks for the advice kanticoy. all this is chinese to me so anything helps and teaches me as well. so I tried gettin spark from all the spark plugs and i got nothing. I noticed thou, that the spark plugs wires are loose and crappy. one of them had only a bit of wire to work with as it shows on the pic. im guessing I have to go out and buy new saprk plug cables and go from there..what do yall think? any suggestions I do in the mean time? ps. I just got the bike so I havent been able to start it, it only cranks up but doesnt start!!
 

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Bike been sitting for some time? Probably dirty points. Is your battery any good? You may very well have some bad wires, but for all 4 to have no spark because they are bad??? Doubt it.
 
74 cb 750 said:
On my spark plugs or if I should change the spark plug cables cause they're a bit loose...thanks!

I always pull the plug out and put it back in the wire and hold it to the engine to ground while trying to electric start.

May sound like a dumb question but is the kill switch in the RUN position? I was fooling around with mine one night and I wasn't getting spark because it was in the OFF position. For me when I'm messing around with the bike and it's in various states things like this are easy to forget.. :)

I've also seen a bad ground cause this as well as points being burnt, not adjusted properly. I'm sure there are threads on checking spark plug wire continuity if you want to search for that as well. Manual is a super investment if you buy but do a search here and you'll find links to online versions for free. Shop reference of wiring diagrams, instructions on coil and plug testing can't be beat.
 
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