Spark Plug Issue?

[CB750Winger]

  I've had my carbs off my '75 CB750 K5 and rebuilt, new plugs, points and pretty much everything else. I've also played with moving positions up and down on the needle jets to zero it in. Valve clearance and timing is dead on. It was running pretty good but then got worse in a hurry and now won't run more than 10 seconds, backfire and die. I take the plugs out soaked with gas, no spark. I clean the plugs and have spark again but does not look real strong. Runs like crap again for 5 seconds and dies. It looks like I have plenty strong spark when I stick a bolt in place of the plug and hold it on the head. Now my question, I put cross reference Autolite spark plugs in it. Now an ex-Honda mechanic buddy of mine told me it will only run good on the OEM NGK plugs. I have an old set I'm going to thro in it this weekend but any of you had this trouble? Thanks!   Paul

[CB750Winger]

   Ok, I answered my own post after this past weekend. I put back NGK D8EA spark plugs in and fired it up, running great now. I learned my lesson about using anything but NGK plugs in this bike.   Paul

[DWightSperber]

That applies to anything not just motorcycles.
GM: AC Delco
Ford: Motorcraft
Chrysler: Champion
Anything Foreign: NGK
You'll find that if you use the stock plugs, the engine will always run better. They design their own plugs because they know what its going to take to make that engine run the best and most proficient.

[CB750Winger]

  You're right about that. My bike would'nt even start with the Autolite plugs. I put Champion plugs in my 71 Ford Torino years ago and they would load up after 1000 miles or less. I'll never buy Champions for anything now. Thanks for the reply

[Polymer-2]

Champions are great plugs..for your lawn mower. Don't think I'd use them in anything else tho.

[Re-run]

These bikes seem to like denso and ngk best. Autolite plugs may not be working properly inside the engine.
if you get new plugs, get ngk D8EA as that is stock.

Sorry, saw you solved it already.