GS1000 eating plugs

[Guest]

I have a 1978 GS1000C. Every couple hundred miles or less, it will kill a spark plug. Generally it's the second from the right, but not always. Upon removal, the plug looks fine. No matter what you do, you can not make that plug ever fire again. It's totally dead.
I have run the bike in total darkness and checked for any shorting to the frame or something, but I see nothing. I run standard NGK B-8ES plugs. I have tried sevens and nines, still fries plugs.
What might it be? I should mention that I have an ill fitting 4 into 1 exhaust. I say ill fitting as it blows some exhaust around the flanges at the head. Could that be part of the problem?
Thanks. Open for suggestions

[OldVet66]

I have a 1978 GS1000C. Every couple hundred miles or less, it will kill a spark plug. Generally it's the second from the right, but not always. Upon removal, the plug looks fine. No matter what you do, you can not make that plug ever fire again. It's totally dead.

If it is another plug other than #3, is it #2 ? 1-4 fires on one coil and 2-3 fires on the other counting from left to right while sitting on the bike 1234. Have you adjusted your valves and set your timing with new Suzuki points and condensers? The leaking flanges are easy to fix. With aftermarket 4-1 pipes replace the gaskets and use two for each pipe. You might need to remove a smashed gasket with a pick and insure the old ones are completely removed. If the flanges are bent in, they are easy enough to straighten out with a vise and a large adjustable wrench. Just be super careful to work the bolts back and fourth and use appropriate removal methods so you don't end up breaking any bolts. Hang the exhaust barely hand tight, tighten the rear mounting bracket, tighten the exhaust flanges. They don't have to be super tight to seal (snug but don't bend the flanges). Use an anti seize compound on the bolts so they can be removed easily later. http://www.z1enterprises.com/ItemDet...em=KL16-5974-1

[tom203]

Stock coils?? I would check secondary resistance on both coils and compare. measure with plug caps removed (wire to wire) and then with plug caps installed.

[oldtimer]

OldVet66, The exhaust does not have those flat diamond shape retainers. The pipes were on the bike when I bought it and uses the stock style flanges. I had the pipes off once to get them ceramic coated. Something doesn't jive here as the outer flanges are larger in diameter than the inner 2. I think they are off 2 different bikes. I have no idea what brand the pipes are as there is no name in them.

[kokar]

read this thread http://www.thegsresources.com/_forum...d.php?t=209557
and check the ignition coils



.

[OldVet66]

I guess it would be possible to have something welded to the pipe to insure even compression from the flanges if that is the problem. The pipe is very similar to a Vance and Hines, but it's hard to tell from the picture angle. The megaphone looks a little longer. What does the mounting bracket look like and is there a rectangular inset near the end of the pipe that might have held a name tag? I can tell you from personal experience that a Dyna-S, electronic ignition, Dyna green coils and their 8mm suppression plug wires are a definite ignition upgrade that would most likely cure your plug problems. Very nice looking bike you have there.

[oldtimer]

Do the Vance and Hines pipes require center stand removal? The pipes I have retain the center stand. There is no indication that a plaque or emblem was ever on them. I can tell you that they were chrome originally. The chrome was pretty shot, so I had it blasted off and ceramic coating applied, The megaphone is slash cut. It kas a packable baffle which is retained by a cone shaped, slightly recessed cap. Te cap is retained by 2 bolts on the underside.

[OldVet66]

That is not Vance and Hines, the baffles are completely different and the V&H is a lot shorter but someone will recognize it from the picture of the baffle.