The Ninja 900 engine was the ancestor to the Concours 1000 engine -- nothing in common with the C14 engine (different engine families) The Ninja and subsequent family engines used forked cam followers with threaded valve adjusters which was a very poor design that had to be adjusted often and caused accelerated cam wear because of faulty valve geometry and sketchy cam metallurgy. ....Shim-under-bucket valve tappets are lightyears superior to that design and that is why Kawasaki finally incorporated it into the current engines. The Ninja engines while strong performers also made tons of valve train racket hence the nickname "Rock-crushers" Additionally those engines had problems with cam chain adjusters that contributed to that "nom de plume."
well, actually there existed a 20 year run of another bike, based on that "crude and atiquated design" called "The Original Concours", ZG1000 / GTR1000. Frankly you generalize this as a pitfall, but there was only one year where Valve metalurgy was faulty (introduction year 1986), and the original design lasted, and still lasts today, a bunch of people called "The Concours Owners Group" can attest to its reliability.
Cam metalurgy problems can a do pop up even today, so laying it all on the valve adjust mechanism is rediculous. The Original Conni required attention around 12k miles, and subsequent adjusts /inspections could begin getting stretched to 20k point after 2 or 3 initial adjustments. The adjustment was a piece of cake, compared to the shim under bucket, which requires a huge skill set for the novice mechanic to undertake, combined with tools not normally in most folks boxes, and a lot of patiance and due dilligence to complete correctly, less the engine will be traumatized. Thereafter, inspect/adjust is substantially easier once maps were made, but still you ain't accomplishing it in an afternoon.
The clearance has to be -0- or less than zero to risk burning a valve. As long as there is any clearance in the valve train at all, the valve will seat and cool.....
..... until it becomes zero at which time the valve will get extremely hot, and possibly hot enough to actually melt the edge where the valve is thinnest (this is what we call a 'burned valve').
Brian
Lets not forget there are 2 types of valves,
exhaust, which will "burn" when they are hanging open, and
INTAKE... which
will not likely burn, but cause extreme carbon fouling and probable piston damage as a result of said fouling, when the buildup becomes thick enough to pinch. Doesn't take that long to occur, we already have had someone post of this problem (carbon buildup and piston fracture) which I noted during his post mortum from his dealers findings was likely caused by this very syndrome.
Just my opinion but I don't think any of us can know what the clearances are really like in any engine unless an actual measurement is made.
Brian
No truer words could be spoken on this. It IS gospel......Look at the diference in clearence for an intake valve, which is cooled additionally by the incomming air/fuel mixture, and the exhaust valve, which is not.
......Also remember that the whole point of valve clearence is when the engine is in it's correct temperature operating range to balance between having the valves close fully and, on the other extream, to have the cam not move so far away from the bucket on the closed/round side that the cam lobe will slam against the bucket when it swings back around to open the valve........
.....Valves can burn even when there is COLD cam to bucket clearance IF the expansion of the parts reduces that clearence to less than zero and results in a valve not fully closing. And to augment Brain's info - valves burn from not closing fully due to BOTH heat not being transfered from the valve to the valve seat AND from the hot exhaust gasses flowing around the valve (as they excape) during the entire combustion process (as opposed to the relitively cooler post combustion gases passing the exhaust valve during the exhaust upstroke of the piston). This is why exhaust valves are more typically the ones that get burnt, and not the intake valves.[/b]
In truth, the specified clearances cold, which allow correct clearance hot, are not designed to "keep the cam from slamming the bucket", but to prevent the bucket from floating enough to allow the shim below, to move and be displaced. The "wiping" action of the cam on the bucket is just that, the most violent activity really is when @ high rpm, the cam leaves the bucket face (as the valve is closing) and the valve under terrific spring presure and inertia slams home against the seat.
...your comment "(as opposed to the relitively cooler post combustion gases passing the exhaust valve during the exhaust upstroke of the piston). This is why exhaust valves are more typically the ones that get burnt, and not the intake valves"... does not apply, this is a 4 stroke engine, during the exhaust upstroke the only valve open is the exhaust.
With this noted, I again say intake valve hanging open will carbon the whole thing up. But if you can burn an intake valve on this engine, you definatly have/had a problem well before that occurs, and the bike will likely not have performed in any manner acceptable or "without knowing" there was an issue. Intake valves just don't ever burn compared to exhaust ones today.
Goldwing's have hydraulic valves... 
and they redline where? and rev how fast?
Discussed it with the service manager at my dealer yesterday. He said their experience has been that you really don't need it until 22-25k miles. He thinks 15k is too early.
When all is said and done, and seeing you are riding a 2011, and not a '08 (made in 2007) first year production machine, you may be closer to safe with his opinions than those of us that stuck out $14k on the "infancy" of this machine, where "iffy" and "varied" tolerances during manufacture occured. I think K may have it dialed in now, but some of us had to make sure, and many of us feel it was wise to do the interval (note I said WE did the job, not a dealer) to insure we were satisfied.
