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Discussion Starter #1
Honda 350 motor with dual plug set up. I can post a photo later. The inboard plugs are NGK C-10H, short small plugs. They are located on the inboard side of the head, under the cam box. There is very little clearance there between the bottom of the cam box and the tip of the sparking plug, roughly no more than .133 (Thanks, Lonewolf)

PVL ignition. The previous owner used the stock PVL rubber boots on the top of the plugs. In order to obtain clearance for the cam box to sit on top of the head, he ground down the bottom of the cam box, too much, and caused a hole to develop and fractures, causing an oil leak. So . . .

I am looking for the best way to connect the plug wire to the plug that has the smallest allowable clearance so I do not have to take anything away from the cam box. I ordered what looks like, in the Tucker Rocky catalog, the shortest connectors there. But . . .

NotNicky has suggested just connecting the plug wire with its little wire springy thing to the tip of the plug and then using electric shrink tubing, say two or three different sizes and shrinking the wire to the plug. Voila? (PS I got a NOS cam box off egay last week to replace the bad one)

My question is, will the lack of rubber insulation make the spark arc to the engine? Or, when it is running, as the plug is connected to the ignition, it will go to the plug regardless? I know that it will try to find the path of least resistance, so is the shrink tubing good enough?
 

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Evil,
What you want is called a 'sparky', we used to use them on mx/dirt bikes, only 1" high, I have 1, send me your address off line and I'll send it to you and I'll dig around the vintage dirt groups and see if they are still available.

dch
 

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Discussion Starter #3
but i need two. so let me know. they are 14 mm plugs.
 

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actually I just looked and I have another one on an ossa pioneer, easily replaced, doesn't need the clearance, they fit on the plugs with the screw on piece on the top of the plug in place, once seated they only stick up maybe 1/4"..

dch.
 

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If those don't work...try the ends of lawn mower plug wires. They connect at a right angle to the plug. ..like this ====o
JohnnyB
 

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Discussion Starter #6
yes but noone has answered my question yet. If a plug is left with, say, just a bare connection, is that OK? Or do you HAVE to have insulation for some reason around the plug tip.
 

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Evil,
You gotta have some insulation...unless the plug end is at least 1" away from anything made of metal...and even then in the rain it would arc 3" through water.
You really do need some type of reasonably thick insulation. Plug caps are such are actually made of a type of material that is more resistant to electrical flow than would be the case with "normal" rubber. When it comes to insulating abilities all materials, even rubber are not equal.
JohnnyB
 
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