I've read a lot of bullHockey lately, and figure as people are analyzing why 2 peoples bikes had failures, I'll just toss this in here... because the same people read and can strain out what they desire from it...
so, regarding the top end failures related to recently, and strictly base on my opinion... here goes....
I'm all about sharing CORRECT and Accurate responses based on MY true knowledge of this bikes
mechanics, HAVING OWNED, and PHYSICALLY SERVICED this bike...
I take great exception to "speculative responses, generically given" based on some other bike, or
familiarity that is not DIRECTLY experinced by the person offering the advice, or speculation...
With that said, a lot of this is bogus... and I won't point fingers at "who says what", but I will set the bar
and say with my knowledge, and hands on "Inside this engine"... the following facts...
it is virtually IMPOSSIBLE to install, and assemble and make engine "fire up", by installing the cam
retainer caps improperly, fact is, they cannot be installed in any manner other than correct, due to the
hollow pilot dowel locations, and the cam sensor location.
the caps are numbered... and, if you examine the picture I am sharing here, directly from the manual, even someone who has never seen the "inside" of this engine, can clearly see this...
the dowel locations in caps and head, are shown as "A", pretty clear...
and the nomenclature, and physical attributes of each cam cap, are unique to their positions.
again,
It is also virtually impossible to "incorrectly" install (mix up which is which) on the oil supply pipes
locations.. simply said, it can't be assembled "wrong" and/or even get the cover on.
look closely at the diagram. Also the configuration of the valve cover casting itself, relegates it impossible to incorrectly assemble it.
As for "spitting out" a shim...? maybe if your shims were at the thinnest end of the spectrum of those
installed, still within clearance... (meaning clearance is correct, but the shims were the thinnest ones
made for installation...like an 1.750mmThick / Number Mark –25, which hopefully will never be see in
"might" get spit out, if the engine hit like 13K rpm, it may jump out of the recess in the retainer.. but then
again, maybe a "max" sized one (like a #75 shim, @ 2.750mm thk), with the correct clearance, could
also, possibly due to it's mass... but because of the diameter? No way... all of these shims, aftermarket
and OEM, as a standard, are very strictly controlled as to outside diameter, and it's relationship to the recess in the
retainer cap. .002", ain't gonna matter...hell, I'd go as far as saying it ain't shifting out of "centralized position even if it was .010" less in Outside diameter.. because that means it can only "shift" to oneside, half that value......open up the engine, remove the cams, pop the bucket out, and put your finger on the OEM shim... and wiggle it... you will see the OEM clearance... it isn't a tight fit by any realm.
I have seen instances in my past, building drag bike Kaws, where after valve regrinds the end of the
stem was not dressed down in conjunction, which allowed the stem to contact the "bucket" (on shim
over bucket KZ engines, Z1's to be specific), which caused the stem retaining collet halves to self eject,
and drop a valve, grenading a top end.. I've never seen a spit out shim on a shim over bucket spit out from anything other than that, or a valve that failed prior, hell those shims sat about 1/8" into a recess.. and even with soft valve springs, you had to work to spit one... I have a '78 Kz in my garage still, and tho it has a lot of work don by my, including some robust valve springs, I could never imagine spitting one out.
But the C14 I find quite bulletproof in it's assembly as seen, and without being a highly modified and poorly done followup. In otherwords, an engine that is in 99.9999% OF THOSE ON THE STREET.
I cannot rule out a "poorly manufactured" valve, with regard to it's groove that retains the keepers, or a
poorly manufactured keeper itself, as these parts are often "sintered powder metal" construction, and
they can fracture., or a piece of debris finding its way into that interface between the keepers and the
retainer, which again could cause a release.
I'm not subject to the "play nice or get kicked out" mentality here, so it's the only place I can currently dismay myths, and incorrect diatribe concerning these bikes, without being threatened by a "board".
keep it real.