2006 ZX 14 @ 9,000 MI.
Its been 4 yrs and 22,xxx miles since i adjusted clearance. First bike that i have done major maint on.
At he time i was on another Forum and ref here and i used The ROOK formula. My bike wasnt starting easily cold. Again , only less than 9,000 mi ODM. After disassembling and getting involved in the valve clearance adj. I came up with the idea that i could extend the next recommended Valve job by taking extra steps now..

Is this a thing or was i over thinking it?
So instead of just settling for each valve being in tolerance @ the time. I used Rooks formula, whatever each clearance was,, i subtracted that from the max allowed, then added that measurement to the shim that came out of that position, then replaced each shim so it was at the max allowable clearance, INTAKE - EXHAUST.. also hoping i can get a longer interval to next next job..
Does this make since, or no - go?
Presently i am about 4-6000 till due again, with no signs of needing adjustment.
I understand that some will try for min clearance for more power. So i felt i could extend the life by doing the opposite. Although there isnt much diff from min to max allowable.
Basically replaced or moved every shim...
@ only 9,000 miles, 3-4 valves were below min allowed tolerance and others were close...
During my explanation here, i might have got the terminology switched around, but i think you should understand what i was thinking.
Its been awhile since i did that...

replaced each shim so it was at the max allowable clearance, INTAKE - EXHAUST.. also hoping i can get a longer interval to next next job..
Does this make since, or no - go?

Sounds very logical. Valves get tight as they wear in. You set them loose so they can wear in for a longer time before they ned to be adjusted again.

Only thing is, I don't think those valves will change much now. Maybe they will for you since you didn't go overdue on the first adjustment. I did mine at 24,000 miles if I recall and then checked again at about 36,000. They didn't move.

I understand that some will try for min clearance for more power. So i felt i could extend the life by doing the opposite. Although there isnt much diff from min to max allowable.

If you set the valves loose, the space between the cam and the lifter is bigger. The cam will not press as hard against the lifter. I'd say that probably would extend wear on your cams.

* Last updated by: Rook on 1/20/2018 @ 6:53 PM *

Its maintenance. The risk is a valve gets tight, get hot and burns a seat/valve and then you are in for $$$ head work.

I tend to be anal about maintenance but, I do agree the trend on these lumps seems to go as Rook has described.

OK,
Im not really concerned about the whole power trip.. I might have mis read that.. But was I on the right track ?
By adding largest possible shim,, did that buy me more time, given that distance will shrink over time,
Or did I do just the opposite ? I added smaller shims
I don't quite understand what is wearing down / away during engine use.

Looking back at the adj procedure,, I would have added smaller shims ??? I think

If the valve was tight, below min spec,, I would have added a smaller shim? Correct?

Im looking at my notes from back then..
All the Exhausts were at or just below minimum allowed,, I added the shim needed to get them closer to the max allowed

The intake,, same

* Last updated by: metalmechanic on 1/21/2018 @ 12:16 AM *

I always shim to the max allowable tolerance. I heard of a guy who grinds shims and sets clearances at the minimum because he thinks it yields max lift and power. My theory is he really likes doing it a lot.

Im not really concerned about the whole power trip.. I might have mis read that.. But was I on the right track ?

I believe we're on the right track-both of us. I don't actually know the prescription for best power via valve shim. Hub is the one who turned me on to it. I'm sure he knows and there must be other info online. I seem to recall hearing about this way back in high school. Nothing new, just probably not a big performance gain. Mighty interesting though.

By adding largest possible shim,, did that buy me more time, given that distance will shrink over time,
Or did I do just the opposite ? I added smaller shims

The shim holds up the bucket. The thicker the shim is, the higher the bucket sits, the closer to the cam = tighter. Put a thinner shim in, the bucket sits lower and clearance between cam and bucket is looser = more space to tighten up as valves wear.

I don't quite understand what is wearing down / away during engine use.

It's all in the intro to the valve clearance tutorial.

http://zx14ninjaforum.com/messages.cfm?threadid=D659042A-D56B-84E2-1C5A7BC825184613&show=0

The part that wears is the valve lip -- the beveled edge of the valve. The valve seat that this bevel rests against Might wear some too over time. I do not believe the valve is supposed to make tight contact with the seat nor should it sit too long against the seat or the valves and seats will burn from lack of heat transfer--that's why you adjust clearances--so the valves DON'T burn into the seats.

See the mushroom bottom of the valve (orange)? It seats into cylinder head (grey). That's what wears in and hopefully will not wear out. The more the valve seal wears, the higher the shim and lifter are raised toward the cam = tighter. Valves get tighter as the seal between valve and seat wears. You can replace valves and seats if necessary.

So you see in the pic above, the shim (purple) holds the lifter closer to the cam or farther away depending on how thick the shim is.

There's a lot more too valve wear. Valve stems can get pounded shorter, Guides can get worn larger in diameter....I think that is all under the heading of 'abnormal wear' or very 'longterm, extended use wear.' I don't see how the valve clearance would impact those situations. That's complete valve replacement time.

* Last updated by: Rook on 1/21/2018 @ 8:59 AM *

My theory is he really likes doing it a lot.

What can change is the mechanical interface between the valve and the valve seat. Too tight and it can get hotter than designed and metal will burn/blow off, too large and more gas than designed will flow in/out and performance is reduced.

Correct on the shim detail, gap is tight requires a smaller shim to increase the gap.

Thanks for the responses.
I had to go back and re - educate myself here.
Theoretically next winter they could be due again. Trying to decipher if my plan was working. As said above. There are no signs of weak starting.. Hold the button firmly for 2-3seconds, Starts every time.
Although i have a second bike now. So ,,this doesnt get as many miles per year.

But, i only need to get valve cover and timing chain cover off to check the clearances..
According to the other posts ive read hear.. I shouldn't expect them to be out of tolerance.

* Last updated by: metalmechanic on 1/21/2018 @ 12:24 PM *

...well engine wires, stick coils too. Throttle bodies removal is desirable and that means the fuel tank, ducts and side subframe rail. If don't think you will be replacing any shims, I guess I would suggest leaving the T-bodies in. You could always put the cover back on and remove the T-bodies after if necessary. Put [ainters tape all over the cover before taking it out. No way you can avoid scraping if you leave the T bodies in...unless you remove the front engine mounts and tip the whole engine forward like I saw someone do recently.

I have heard lots of talk about how checking and adjusting valve clearances is unnecessary as long as there are no untoward sounds emanating from the engine. This is mostly people who are lazy, scared to know or too cheap to pay someone to look into it. The fact is, until you open it up and check, you have no way of knowing what's going on in there. If you pull the cover and all the clearances are good, more power to ya. If you track individual valves at each check, you know which ones to check first, since they are the ones with (probably) diminishing clearance.

I think most of the wear occurs at the seat/valve interface. Everything else is fairly well lubed and cams rubbing on bucket tops put very little side stress on the stem/guide interface, which, due to lack of lubrication, is the second placed wear will occur. The cam lobes, bucket tops bucket bores et al will see very little wear in the lifetime of an engine.

* Last updated by: Danno on 1/22/2018 @ 4:35 AM *

I think most of the wear occurs at the seat/valve interface.

For once, the liberal ideologue hits it out of the park. That is exactly why valve lash crawls toward zero.

The narrow minded conservative said it too! Everyone agrees. See how nice it is when everyone gets along?

For once, the liberal ideologue hits it out of the park.

The narrow minded conservative said it too! Everyone agrees. See how nice it is when everyone gets along?

.
Things would go a lot nicer if people kept the political banter in the off topic section.

OK lets talk busas and Taylor Swift

nothing political there.