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[joppalad]

Hi there, I am overhauling my 500 std engine, and would like to know what is involved in converting the cylinder head to a twin plug arrangement.
Is there more to it than just fitting a plug in place of the valve lifter. I have to fit a new coil, so await the outcome of your responses.
Thanks to everybody.

[joppalad]

Hi there ,
may I correct myself, it should read decompressor instead of valve lifter.
cheers.

[PeteF]

Mr H has a twin lead coil but why would you want two sparks on a standard engine? I suppose if one plug packed up you could continue with the other one but you would probably never know as the engine isn't going to perform any better with two.

[Mark M]

As Pete says,not really worth it on a standard engine, you probably get just as much improvement using electronic ignition and Iridium plugs. A tuned engine is a different story!
REgards, Mark

[ChrisD]

Joppalad. I have done this and it has proved (on my 1996 tuned 500 Classic) to be very successful. And I have retained the use of the decompressor. Look down a few weeks below and you'll see what I mean - and all from direct help from this excellent site. You'd have to take the head to a machinist to make a block to screw into a ne threaded hole in the finned area at centre of the head, drill a 2mm hole from centre of combustion chamber vertically through head so that the decompressor can be seated there. Yes there is enough space anmd it works perfectly.
Cheers
ChrisD

[joppalad]

Thank you,thank you,thank you, CrissD,
You actually answered the question I asked.
My thinking is to fit a valve lifter (Mr H ) in place of the decompressor and have a bit more reliability.

Cheers

joppalad