when my old Vincent motorcycles http://s67.photobucket.com/albums/h298/1951otter/?action=view&current=3196190-R2-050-23A.jpg &&
http://lsvoc.vincent-hrd.co.uk/images/1950TouringRapide.jpg
ran in double valve guides and had specialoid pistons running a .006+ cylinder wall clearance and NO valve guide seals, the ignition was 50 degrees and ran on a Lucas magneto, http://www.jampot.co.nz/images_trade_ads/doug_banks.jpg the plugs would always wisker. that fine line arc covered by a film of oil would short the plug out. so i always carried a spare set. mostly it was the rear plug because the 50 defree V and the Lucas mag had the rear as a weaker arc to fire that cylinder. my plugs were newish as i could not get but a couple hundred miles out of them. i cleaned them every week it seamed.
they now make very nice pistons and viton valve guide seals. i now run a heavily modified kabota tractor perminate magnet alternator , made one at a time by a machinists/ pipefitter in canada, http://www.iowamotorparts.com/images/KUB-A1-TO.gif to a 60 years old distributer and she fires just fine now.

Last edited by carolines truck; 11/29/2008 7:24 PM.
Jim & Caroline
The highway is for gamblers, better use your good sense."
Gooday-that's my 1¢ answer due to the lousy economy ~ cause I ain't got - no . mo . doe
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