I have had a customer come in complaining that his S+S knucklehead seems very under powered. He says that it seems comfortable cruising at about 55mph and that about it. Having taken bike for a ride he was right. Something very wrong. It felt very sluggish and also noticed oil coming out of exhaust ports. Alarm bells start to ring. Checked compression. Very down. Time to investigate further. Took heads off to find guides very sloppy. Hence oil down exhaust. Noticed also rockers seem to be hammering inside of knuckles. This is not usual S+S quality. Apparently engine only got 600 miles on rebuild. Time to look further. Turns out the cases are pan/shovel cases according to S+S. And they were made prior to there knuckle engines. So this has been cobbled together. Time to measure and inspect all parts as it is a bitsa of an engine.Reason for damage to knuckle/rocker combo as you can see in photos. The valves installed have almost over an eigth of an inch more valve stem protrusion. Also wrong style cam. It was fitted with an Evo cam!!!!. It now fitted with all new kibblewhite black diamond valves, guides collars and keepers. You can buy all of this as one part number. You can use other guides but have to machine them to get correct clearance between collar and guide. I wont need to do any clearancing as rockers already have done this. Now got a bolt in cam from sifton with bit more rumpety rump. Now should cruise more effortlessly at 70/80 mph
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