Hi Hal,
I always, I keep great records, and have pictures of everything including, failures, modifications, upgrades, dyno tests, design changes, and suggested improvements on camshafts & lifters. So it will be easy to supply most of the requested information. In fact all the camshafts I sold over the last several years included detailed information collected from a special setup using a dial indicator over each valve. The included sheet had information on centerlines, profile, duration, lift, lash, and opening and closing [both advanced & dot to dot].
So the information will be of great interest, but most of the data centers around durability, not performance. While it is true I have produced some of the fastest motors, and hold many records, my motives were to make the valve train "bullet proof". After a great deal of research [never too old to learn], I learned the importance of valve stress, clearances, spring pressure, valve spring rates [progressive vs normal], valve guides, valve seats, lifter size & weight, combustion ratios, and "what not to do".
I will attempt to answer your questions, but if I confuse the issue, just ask again. First I will discuss advancing the camshaft, the 1999 motor was set dot to dot, but the 1999 service manual detailed advancing the camshaft one tooth to stop the motor from running too rich. I don't know exactly when, but somewhere during the later NE motor production the camshaft was advanced by the vendor, it is impossible to guess when or why because no service manual was ever supplied on the later motor. Why advance the camshaft, and what are the net results? When the camshaft is advanced it effects the opening and closing times of the valves, and alters the compression [a small amount]. During early tests I compaired the valve timing to the vintage motors [1938 to 1952] with the earlier 1999 motor and discovered the numbers were much closer when the camshaft was advanced. In fact when I retarded the camshaft on the vintage motor it also ran rich, but was impossible to keep running, and very hard to start, it is also important to note the camshaft gearing is different between the two motors, so the change was more drastic. You just need to know if the camshaft is advanced one tooth it supplies the best overall performance. Early in the NE production I discovered a serious mis-match between the camshaft lobes [lift] and the 10 MM lifters [I have lots of pictures showing the destruction of the camshaft lobes] and after a lot of research [Ron Dow, and 2 leading camshaft companies in NC] it was determined the lifter base wasn't wide enough to "roll" over the lobes, but in fact "danced" down the lobes. I quickly discovered a very simple fix......mushroom lifters. My first set was vintage lifters [removed from a 1948 "J" motor] cut down to fit the 10 MM lifter bores [second set was set to Ron Dow for high speed testing] I cut the lifters to .393" except the bottom 1/8" [.500" O.D.], and an un-expected side effect was reduced valve train weight. This information was sent to the company, and I think somewhere in 2007 it became a production item [but not exactly the same]. Of course I tested and checked the difference in performance, but even on the test jig with the dial indicators, it was impossible to notice much difference in duration or valve timing. There was one big difference, and it was the length of time the valve was held wide open. And it was this difference that aided the small increase of power. During several dyno & "Roller Road" tests it resulted in very similar power, but the torque increased and moved slighty higher up the curve. The real difference was noted on highly tuned motors, and did make a major difference [3 MPH, 65MPH to 68 MPH].
One question asked "Finally, what about a dyno comparison between stock valve timing with stock lifters and "one degree" timing with mushroom lifters?", I can not supply the answer because I never tested "stock" lifters once I discovered the problem of lifter/camshaft mismatch.
One additional comment concerns the valve springs, the correct way to install the "progressive" valve springs is the "tight" winding against the valve guide [information supplied by Kurt M.], not against the retainer. I have discovered some motors have one spring one way and the other different, some motors have one regular spring and one progressive, some have both springs upside down, some have two stock springs, and some are installed correctly, but is worth the effort to install them correctly, because the motor performs smoother througout the entire RPM range. The lobes on the camshaft can not exceed .212" on many motors because the lobes will hit the crankshaft, and the base of the mushroom lifter must be kept to a minimum or can jam between the camshaft lobe and the case [can cause the "pressed" gear to spin on the camshaft].
This information is not entended to "bash" anyone, just to help you improve the durability of your motorbike. If anyone wants pictures, email me at
quincy163@yahoo.com
Have fun,
Quenton