Guys, I'm writing this here because there are a lot of threads past and current about how to build an engine, what works, what doesn't and what's best bang for the buck, ect. I've just experienced something that is certainly new for me - "head work only" to a stock engine.
I've just gotten my new build broke-in and for the first time since - hammered it good today. This is a testiment to good valve work and polishing and cleaning of the ports. This was what I call a stock build. I simply ball-honed the stock-bore cylinders, Mike Rieck had my 100% stock, 18,000 mile pistons Swain Coatings moly-coated (to make the skirts last forever), new stock rings and clips installed, the original 18,000 mile factory cams were perfect and exact to specs so reused, Kibble White SS valves, keepers, guides, Viton seals, (thanks again Mike!) the original springs were exact to specs for height and lean angles so re-used - in all, this motor went back to stock specs - except I had the head "cleaned-up" - some minor bowl work, all casting flash removed, and a Serdi multi-angle valve job done. With stock exhaust, stock airbox and snorkel all stock - she sizzled the rear when I hit 2nd hard. I've rode a bike exactly like this 32 years ago, this is the same model bike my wife and I used to date on over 30 years ago - that bike would never - never do more than bark the tire. I wasn't going after a tire spin - I was actually checking to see if the 20/50 oil I changed to would solve the oil-pressure light coming on during hard acceleration (it did).
Long story short, never contemplate a build on any old bike (especially these old 2 valver head modles without a good porting job. This build has taught me that even when making mild and non-intentional improvements to the head's flow - the results are dramatic. If I were to add serious porting, big valves, 32mm carbs, big cams (oops I did say plural) and 1,015 cc - my little 836 won't measure up.
end of story - Gordon
