Kawasaki Concours Forum
The C-14, aka Kawasaki Concours-14, the new one :) => The Bike - C14/GTR 1400 => Topic started by: C14-Pilot on January 14, 2012, 01:33:14 PM
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I bought my c14 in August of 08 and about a year and a half later when I got 15K miles on it I took it to my dealer and
asked him if I should have the valves checked. I told him that I had read where the same bike sold
in California the manual states that the valve adjustment should be done at 25k instead of 15k.
He called Kawasaki and asked them at what interval the valves should be checked and they told him
that the engine should be fine until at least 25k so I did not have it done at the time.
So later when I got 25k miles on it I took it back to the dealer and told him I was ready to have the 25K
valve adjustment done and He said if the engine sounded good with no noticeable valve noise He would
not think the valve check was necessary. At this point I was not sure if I should trust what the dealer was
telling me or not so I took it to a second dealer.
I asked this second dealer to give me an estimate on getting a valve check and adjustment done and I did not mention
what the other dealer had told me. The second dealer told me the same thing the first dealer did, he said that if
there was no noticeable engine noise He did not think it was necessary to do the valve check so I put it off again.
I took my bike to the original dealer this week to have a leaking valve cover gasket changed under warranty.
I asked the dealer to check the valves while He had the valve cover off and I gave him a shim map and ask him
to record his findings when He checked the valves. I got at an email from the dealer and He said that the valve
clearances were spot on and He had attached the shim map that I had requested.
I have attached the shim map, the bike now has 37,300 miles on it.
What do You guys think? Is it possible that after 37,300 miles there is no adjustment needed???
The dealer had ordered the wrong valve cover gasket so I did not get my bike back until today 01/20/12
I got my leaking valve cover gasket replaced "warranty covered" , valves checked and plugs replaced and
all I was charged was for the cost of the plugs $36.42. I believe the dealer treated me RIGHT!
He did not charge me anything for checking the valves and doing a shim map since He had the valve cover
off to replace the valve cover gasket. I will post pictures tomorrow of the plugs so You guys can see what
they looked like after 37k
Later,
c14-Pilot
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Unlikely, but it is possible. The biggest thing is that you have documented proof that the valve check was performed, so you are covered by the GTPP if you have any problems.
I don't know what was changed on my first valve check since the previous owner had that done but I didn't get any paperwork. My C14's second valve check (I did it myself) there were no shims needed. Then my third (dealer did it when they changed my valve cover gasket under warranty) they provided me with a shim map and there were no changes needed again. All the measurements were within .001 from when I checked them 25,000 miles ago. My bike currently has 42,000 miles on it and I will probably wait until 70,000+ before I check the valves again unless I notice any issues.
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Sure, and apparently you have a prime example in your possession.
Even when the valve lash is out of spec., it is not out by much in the cases I have seen. The thing to remember is that Kawasaki used the tolerance and may well have set some valves to the limit of that tolerance, either on the high or low side. So when an owner finds a bike that is outside of tolerance that person tends to assume that the clearance has changed from the middle of the tolerance but that is probably not the case; the clearance most likely started off very close to the current clearance but just inside the tolerance range. Also, it seems that most folks assume the clearance changed in a linear fashion over the miles on the bike and that again is probably incorrect; the clearance would change the most in the first few miles on the engine as the valves finish seating. After that the change in clearance is probably minimal over a LOT of miles. I think your example is a lot closer to typical than a lot of people would assume and <most> bikes could go their entire life without ever needing valve shims changed. Unfortunately there is no way to know without actually doing a valve lash check.
Brian
<snip>
I have attached the shim map, the bike now has 37,300 miles on it.
What do You guys think? Is it possible that after 37,300 miles there is no adjustment needed???
Later,
c14-Pilot
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I dont know if I buy into the idea of noisy valves needing adjustment. On the dirt bikes, which are very similar, the valves tighten up and get quiet. Noise is a better thing to have than no noise.
Other than the interval being WAY sooner for the dirt bikes, I woudl expect the c14 to be the same.
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I dont know if I buy into the idea of noisy valves needing adjustment. On the dirt bikes, which are very similar, the valves tighten up and get quiet. Noise is a better thing to have than no noise.
Other than the interval being WAY sooner for the dirt bikes, I woudl expect the c14 to be the same.
+1 A noisy valve is a happy valve- a tight valve can burn due to incomplete closing .
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+1 A noisy valve is a happy valve- a tight valve can burn due to incomplete closing .
Yeah, what he said.
This happened to a Honda friend of mine. The bike was one only produced a couple of years and getting a head gasket was a bit of a pain. Bike runs good now.
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While I agree that absence of valve noise is no substitute for a valve check, I see no reason to doubt your mechanic based on the info you posted. The shim map looks legitimate to me. And I tend to agree with Brian that most engines typically don't go out of spec withen 40,000 miles.
In 40 years of riding I have never known anyone who had a valve clearance related failure and I have two long time riding buddies who never bother to have their valves checked.
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Not too hard to make a bogus clearance sheet.......just sayin. As for me, mine won't be getting checked till 20k. And a big +1 on what Lather just said!!!! :thumbs:
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OK, I am going to chime in. First of all, all U.S. C-14's (yes, even California models) are specified by Kawasaki to perform the valve clearance inspection at 15,000 miles (24,000 kilometers). Every where else in the world, that valve inspect interval is at 26,000 miles (42,000 kilometers). That your dealers didn't recognize this would be a warning alarm for me.
Secondly, I am worthless and weak and easily swayed by nice riding weather, and I rationalized putting off my check because of others reported findings and the above interval discrepancy, until 23,500 miles. I am in the middle of it right now. Every single one of valves was on the tight side of the specification, or .001" out of spec to the tight side. Every one will be adjusted toward nominal. Most others here have found very little to worry about during their checks, but most have also noted the valves tend to the tight side.
If yours are all near mid-spec nominal, as shown in your map, that is very cool and not unprecedented. In my case, waiting until 37,000 miles wouldn't have resulted in any real valve noise, but it very well could of led to burned valves.
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Ok, thinking of getting an older C14 and have been watching the discussions on valve adjust intervals because I'm not hip on having to spend $600 or so every 15,000 miles but I could live with 25,000.
Now, thinking of noisy vs quite and the different rationales - is it possible that shim under bucket setups get noisier as they get more miles whereas the screw/locknut tappets get quieter? I've had a couple Toyota dealerships tell me if the valves arent making any noise (4.7L Seqouia, shim under bucket) don't worry about it and though the owners manual says check clearance at 60,000 miles they have never had to adjust the valves.
On that note, thinking about the 60k Toyota interval, I'd also factor in the C14 adjust intervals in accordance with how hard you ride, ie, if you spend a lot of time near redline then I'd expect the valve adjust interval would be closer to 15k.??
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This is a perfect example of what I was mentioning earlier: it is natural to assume that since you were 0.001" below tolerance at 23.5K miles that the clearance tightened linearly (or evenly) during those miles. I propose two things about that- the first is that the movement occurred very early in the bike's use and then stabilized. Because no one ever checks the clearance at 1,000 mile intervals from new, we simply do not know when or [when how much] of the clearance changed. If the clearance was set to the low side initially (during the engine assembly) and then as the valve train seated the clearance tightened in the first 500 miles, it is entirely likely that the clearance had not tightened in thousands of miles. The second thing is that merely being 0.001" under tolerance is no where near -0- clearance and the possibility of burning a valve because it could not close. Again, I do not believe it is a linear thing.
Nothing wrong with checking the valves at the specified time, I am merely saying that we really do now know what has happened when we examine an engine with XX,XXX miles on it and find the clearances are out of tolerance. And I don't think it is anything to get overly worried about at any rate.
Brian
OK, I am going to chime in. First of all, all U.S. C-14's (yes, even California models) are specified by Kawasaki to perform the valve clearance inspection at 15,000 miles (24,000 kilometers). Every where else in the world, that valve inspect interval is at 26,000 miles (42,000 kilometers). That your dealers didn't recognize this would be a warning alarm for me.
Secondly, I am worthless and weak and easily swayed by nice riding weather, and I rationalized putting off my check because of others reported findings and the above interval discrepancy, until 23,500 miles. I am in the middle of it right now. Every single one of valves was on the tight side of the specification, or .001" out of spec to the tight side. Every one will be adjusted toward nominal. Most others here have found very little to worry about during their checks, but most have also noted the valves tend to the tight side.
If yours are all near mid-spec nominal, as shown in your map, that is very cool and not unprecedented. In my case, waiting until 37,000 miles wouldn't have resulted in any real valve noise, but it very well could of led to burned valves.
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I propose two things...- the first is that the movement occurred very early in the bike's use and then stabilized...Again, I do not believe it is a linear thing.
Nothing wrong with checking the valves at the specified time, I am merely saying that we really do now know what has happened when we examine an engine with XX,XXX miles on it and find the clearances are out of tolerance. And I don't think it is anything to get overly worried about at any rate.
Brian, I completely agree. Also, it fits neatly into my rationale that with the valves set slightly to the loose side of nominal I should EASILY get another 25,000 miles without checking again. :thumbs:
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I have not had mine checked yet, but I'm at 29,000 miles and plan to soon. But I will confirm what has been said. Two different dealers in Houston have told me it's a waste of time and money to check them anywhere near what the factory recommends. I don't actually recall what one of them told me as it's been quite a while ago. The other one told me that at the 26,000 miles I had on it at the time that it might not be a bad idea to have them checked, but they don't expect to find any out of spec. BTW, the service manager at that dealer owns an 08 Concours, and the parts manager owns a ZX-14.
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I have a '99 Mazda 626 with solid valve liters and shim under bucket adjusters. Mazda also tells their dealers that if the valves do not make any noise, they do not need to be adjusted. Unfortunately, this may be deceptive in cases where the clearances are too tight, which is undesirable, as it can lead to valve burning.
As it is, I checked the valve clearances for the first time on my Mazda at 290,000 miles (yes you read it right) and only two out of 24 valves were just above the upper limit of the adjustment range. So I did not do anything. Now at 322,000 miles the engine is doing just fine.
Keep in mind that shim under bucket adjusters are much less likely to come out of adjustment than screw type adjusters. I have an older diesel Mercedes 300 DT with screw type valve adjusters and the valves clearances come out spec a lot more on that one. This is why Mercedes requires these to be adjusted every 15k miles.
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This is a perfect example of what I was mentioning earlier: it is natural to assume that since you were 0.001" below tolerance at 23.5K miles that the clearance tightened linearly (or evenly) during those miles. I propose two things about that- the first is that the movement occurred very early in the bike's use and then stabilized. Because no one ever checks the clearance at 1,000 mile intervals from new, we simply do not know when or [when how much] of the clearance changed. If the clearance was set to the low side initially (during the engine assembly) and then as the valve train seated the clearance tightened in the first 500 miles, it is entirely likely that the clearance had not tightened in thousands of miles. The second thing is that merely being 0.001" under tolerance is no where near -0- clearance and the possibility of burning a valve because it could not close. Again, I do not believe it is a linear thing.
I strongly agree...but how tight do the cold clearances have to be before a burned valve can become a reality? How much of a safety margin is built into the low tolerance spec?
There is a long running thread at the fjrforum.com about what FJR owners are finding when they check their valve clearances and one rider just reported that he did his first valve check at 89K and everything was fine except for one exhaust valve that only had a .002 clearance (spec is .007-.010). When he checked the valves again at 156K, he had one intake valve at .005 and several others that barely were within the spec of .006-.009. It appears that the .002 exhaust clearance he found at 89k did not result in any damage to the engine since that was the same bike that turned 150K miles when he rode (and won) the 2011 Iron Butt last June.
On the flip side, last fall another FJR rider did actually burn valves at 50K, the first water cooled engine that I had heard of, but he had never done a valve check. His FJR was probably the 1 in a thousand that really needed a valve adjustment at 26K.
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My old '98 Honda CRV had screw adjusters that the manual said didn't
have to be checked until 105k. I thought this a long time to go, plus the same engine, when installed in the Acura coupe, was spec'd for valve check at 50k miles. I
checked them at 50k and 100k miles, then sold the car, it ran great.
Some people were foolish enough to believe their car could go over 100k miles without a valve check. Some found that they had burnt exhaust valves and needed a valve job costing over $2k! Some more vocal owners were able to get a discount on the work from Honda under their "goodwill program".
My experience with valve checks is that most valves will probably be in spec, a couple can be way out. After none or two checks, valves take on a set and seemed to stay in spec a long time. Noisy valves are not necessarily good as they can cost you a little power. Quiet valves can be tight valves, not good either. Judging whether your valves are in spec makes as much sense as a doctor guessing your blood pressure.
If I took my bike in at 25k miles and they said every valve was in spec, I'd think they didn't check them.
Tell you what, if you take your bike in at 25k miles and have it check and they don't check them like you paid for and leave you with a few tight valves, then....
at 48k miles, bike still in warranty, you take it in and it has a couple of burnt valves, I bet Kawa will tell the dealer to fix it on their dime.
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Wayne my gear head windsurf buddy says
Noise is Good
or at least better that a burned up valve
I had my 1000 mile ck
had one adjusted
payed the$$$
now I'm waiting till 25k
btw
Mt Hood got a foot of snow
glad I went fro a ride saturday morning when it was warm n sunny
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"noisy" is rather hard to quantify in the context of casual discussion. Everybody is likely to have a different idea of what a noisy valve sounds like vs a quiet one. Additionally it takes a good, trained ear to distinguish from the various sounds coming from an engine.
What I was tought many years ago by a Kawasaki dealer mechanic was that valve clearance noise should be noticeable on cold startup but should almost go away by the time the engine is up to operating temperature. The object of this lesson was a1984 Ninja 900 engine, the first ancestor of our C14 engines. However it did have thread valve tappet adjusters. However I believe the same holds true for Shim under Buckets as the source of the noice is metal to metal contact (cushioned by a film of oil) as the clearance is taken up.
On my second valve adjustment on my C14 I think I got a pretty good result in terms of measured values and the audible results as described above reflect it. That was at 55,000 miles or so. I feel comfortable planning to do the next check based on how the engine sounds.
edit: I did not word that well. What I meant is my next valve check interval will be stretched beyond the specified 15000 miles depending on how the engine sounds.
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The object of this lesson was a1984 Ninja 900 engine, the first ancestor of our C14 engines. However it did have thread valve tappet adjusters.
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. Very much the same problems as the 1st Gen Honda VFRs. 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."
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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. When a valve cannot seat at any time during the running cycles, the only way left for that valve to cool is through the valve stem, which is a lousy way to transfer heat (from a large area down a small shaft), or through induction cooling, another poor way to try to keep a valve's temp. within acceptable bounds. So in reality, as long as there is -some- clearance the valve face will rest on the valve seat and transfer heat away. This is not a linear thing at all- the temp. of the valve will not rise appreciably as the clearance becomes less and less 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
I strongly agree...but how tight do the cold clearances have to be before a burned valve can become a reality? How much of a safety margin is built into the low tolerance spec?
There is a long running thread at the fjrforum.com about what FJR owners are finding when they check their valve clearances and one rider just reported that he did his first valve check at 89K and everything was fine except for one exhaust valve that only had a .002 clearance (spec is .007-.010). When he checked the valves again at 156K, he had one intake valve at .005 and several others that barely were within the spec of .006-.009. It appears that the .002 exhaust clearance he found at 89k did not result in any damage to the engine since that was the same bike that turned 150K miles when he rode (and won) the 2011 Iron Butt last June.
On the flip side, last fall another FJR rider did actually burn valves at 50K, the first water cooled engine that I had heard of, but he had never done a valve check. His FJR was probably the 1 in a thousand that really needed a valve adjustment at 26K.
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Yes, that is very true and another big problem going by sound is which of the 16 valves is making how much of the noise? Put another way, can anyone realistically pick the [too quiet] valve out of all 16 on a running engine? I don't think so. And three or four overly loose and therefore noisy valves will overcome any number of quiet ones.
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
"noisy" is rather hard to quantify in the context of casual discussion. Everybody is likely to have a different idea of what a noisy valve sounds like vs a quiet one. Additionally it takes a good, trained ear to distinguish from the various sounds coming from an engine.
<snip>
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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. When a valve cannot seat at any time during the running cycles, the only way left for that valve to cool is through the valve stem, which is a lousy way to transfer heat (from a large area down a small shaft), or through induction cooling, another poor way to try to keep a valve's temp. within acceptable bounds. So in reality, as long as there is -some- clearance the valve face will rest on the valve seat and transfer heat away. This is not a linear thing at all- the temp. of the valve will not rise appreciably as the clearance becomes less and less 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').
Agree....but you are referring to the necessary clearance after the valves are hot. My question is how much clearance is actually needed when the valves are cold in order to achieve the zero (or slightly larger) clearance to prevent burning when the valves heat up to normal operating temperatures. I have never seen any data on how much the clearances actually change going from cold to hot but it doesn't seem to be much on a modern water cooled engine.
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it's a waste of time and money to check them anywhere near what the factory recommends.
+1
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Yes, that is very true and another big problem going by sound is which of the 16 valves is making how much of the noise? Put another way, can anyone realistically pick the [too quiet] valve out of all 16 on a running engine? I don't think so. And three or four overly loose and therefore noisy valves will overcome any number of quiet ones.
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
I agree with that. But I think careful listening is a useful tool in deciding how long to stretch the interval.
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Two thoughts:
"On the flip side, last fall another FJR rider did actually burn valves at 50K, the first water cooled engine that I had heard of, but he had never done a valve check."
- Water cooling and valve burning are not directly related. It is true that water cooling provides a much narrower range of operating temperatures and permit closer tolerences because there is less heat related metal expansion. How much expansion of these parts occurs from heat you ask? 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.
An engine has a tollerence range, and since the cam to bucket interface is "protected" by a film of oil the impact of the cam lobe on the bucket is cushioned and lubricated - that tends to be where the "slop" in the operation occurs (as opposed to valves not closing fully). The cam to bucket impact has to be pretty significnt before the oil film is stripped away and metal to metal contact and wear occurs. This is why loose valves are genterally considered to be less of an immediate risk to the engine than tight/not fully colosing valves, both can cause damage but one generally takes longer. Remember too that because heat is the quickest variable to change that a valve that is "tight" but still fully closing at normal operating temperatures may not seal fully and start to burn (erode valve material) on a hot day while you're blasting up a mountain and using a lot of throttle....
Agree....but you are referring to the necessary clearance after the valves are hot. My question is how much clearance is actually needed when the valves are cold in order to achieve the zero (or slightly larger) clearance to prevent burning when the valves heat up to normal operating temperatures. I have never seen any data on how much the clearances actually change going from cold to hot but it doesn't seem to be much on a modern water cooled engine.
- 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.
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I have not had mine checked yet, but I'm at 29,000 miles and plan to soon. But I will confirm what has been said. Two different dealers in Houston have told me it's a waste of time and money to check them anywhere near what the factory recommends. I don't actually recall what one of them told me as it's been quite a while ago. The other one told me that at the 26,000 miles I had on it at the time that it might not be a bad idea to have them checked, but they don't expect to find any out of spec. BTW, the service manager at that dealer owns an 08 Concours, and the parts manager owns a ZX-14.
By any chance is that Pasadena Kawasaki? That's where I bought & take my 09.
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True, the <real> clearance is important when the engine is hot but even hot is a relative word. The valves will be a lot higher in temperature on a bike climbing a long grade, heavily loaded, than they are on a bike gently riding down the street at 55 MPH with no appreciable weight or load.
The key here is temperature, or more accurately, the temperature difference between the valves and the head.
<caution: technical explanation ahead :D >
Aluminum has twice the expansion rate of steel (13 millionths of an inch, per inch, per degree F vs. 6.5 millionths of an inch, per inch, per degree F) and if we assume the valve length to be approximately the same as the head height to under the cam bearings (it is not but pretty close) then we can predict the change in clearance pretty well.... kind of. Let's take ambient or 'cold' temperature to be 70F, and a head that is up to temperature of 230F. That means if the head is 2" tall, and increases in temp. by 160F then the head increases in height about ( 160 * 2 * 13 X 10^-6) 0.00416" or approx. 4 thousandths of an inch. We would have to assume the head is all at the same temperature (it is not but close enough) and does not change much under usage (again, close enough on a water cooled engine) and the change in head height would increase valve lash by ~ 0.004". Now for the valve expansion which is far more tricky: we could assume they are a constant temperature but they are NOT and are much hotter toward the valve end than they are on the tappet end. Also, as the engine produces more power (is under more load), the valves run considerably hotter than when the engine is lightly loaded. In fact, all poppet valve engines will have the exhaust valve glow (at least 900F) under extreme load such as a max. effort. dyno. run or top speed run. So guessing the valve's average temperature under varying load and across its entire length is pretty much impossible really. And here comes the really interesting part: if the valve is less than about 400 F average, then the valve train clearance will actually INCREASE from cold! At, say, 350F (again, average temperature as the 'business' end of the valve will always be hotter than that) we would have: ((350-70) * 6.5 X 10^-6 * 2) = 0.00364" or approx. one- half thousandth less expansion than the head (0.0005"). As the valve temp. increases, the clearance will again reach the same level as it was cold, (approx. 400F average), and then as it rises still further, valve lash would continue to decrease. I would assume that Kawasaki picked a clearance based on a temperature the valves <cannot> ever reach and therefore the lash should not ever go to -0- or less (less being a valve that is 'hung open' all the time). By the way, as exhaust valves run hotter than intake valves, that is the reason why the lash value is always larger on exhaust valves than it is on intake valves- they simply do not expand as much because they do not get as hot.
I guess the really important question is how low can the valve lash be under the worst condition? Also it must be mentioned that momentarily hanging a valve open is not necessarily a problem because it would not be held there long enough to get hot enough to melt. In other words, if a couple of exhaust valves hung open for a few seconds during a drag race it would <probably> not be a problem. It is the continuous use of engines under high power output situations that tend to burn valves- road vehicles are generally not a problem but boats and especially aircraft have been problematic in that area for decades.
But in the end, I doubt there is much risk of 1) the valves really reaching -0- lash or below under any street riding circumstances and 2) the actual lash is not really important as long as there is at least some (as opposed to none) and it is not a ridiculous amount- 0.050" (fifth thousandths of an inch) or approaching 1/16" is far too much clearance and would pound the valve train to death pretty quickly but then again that would be closer to carpentry tolerances than precision engine dimensions.
Brian
Agree....but you are referring to the necessary clearance after the valves are hot. My question is how much clearance is actually needed when the valves are cold in order to achieve the zero (or slightly larger) clearance to prevent burning when the valves heat up to normal operating temperatures. I have never seen any data on how much the clearances actually change going from cold to hot but it doesn't seem to be much on a modern water cooled engine.
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True, the <real> clearance is important when the engine is hot but even hot is a relative word. The valves will be a lot higher in temperature on a bike climbing a long grade, heavily loaded, than they are on a bike gently riding down the street at 55 MPH with no appreciable weight or load.
The key here is temperature, or more accurately, the temperature difference between the valves and the head.
<caution: technical explanation ahead :D >
Very interesting....................................thank you!
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Very good info here, but I still wonder why in this day and age of vast internal combustion technology does any engine need adjustable valves? As I understand it hydraulic valves produce less horsepower than conventional valve set-ups.
I can see where the squids and tuners would want the conventional set-up but why does a sport-tourer need it?
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Very good info here, but I still wonder why in this day and age of vast internal combustion technology does any engine need adjustable valves? As I understand it hydraulic valves produce less horsepower than conventional valve set-ups.
I can see where the squids and tuners would want the conventional set-up but why does a sport-tourer need it?
Mechanical valve actuation, vs. hydraulic, permits higher RPM and, most importantly with an interference engine design, better control of the valves/less "float" at high RPM.
Do you "need" mechanical valve actuation on a S-T bike? No, but then you can't ever have too much power.... ;)
Goldwing's have hydraulic valves... ::)
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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.
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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? 8)
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.
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MOB -- if you will reread my post, I did say that the Ninja was the progenitor to the Concours 1000 (ZG1000) engine. I bought a new 2002 C10 and when I performed the 600 mile valve check, my cams were already scuffed and by 5000 miles, the cams were beginning to pit and had places where the hardened surface had worn through. This was a VERY common occurrence in all years of the 1st Gen Concours engines and it was thoroughly discussed on the old forum.
I had a lot of experience with the 1st gen Honda VFRs and they had the exact same issues and an engineering analysis revealed faulty rocker geometry, 2 heavy valves springs acting on a single cam lobe and lack of upper oiling led to rapid cam wear.
That said, I have personally observed many high mileage C10s despite the cam pitting problems, so it didn't really reduce reliability to an appreciable degree.
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I find it difficult to believe that so many valves stay in spec. On my 2008, I did my first adjustment at 24,700 miles. I had 8 that went to the next shim step down, 7 that went two shim sizes down, and one went four shim sizes smaller! Went from a #20 shim to a #10. Not a single valve was in spec.
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I find it difficult to believe that so many valves stay in spec. On my 2008, I did my first adjustment at 24,700 miles. I had 8 that went to the next shim step down, 7 that went two shim sizes down, and one went four shim sizes smaller! Went from a #20 shim to a #10. Not a single valve was in spec.
Most doing it themselves find them out of spec, it is the stealerships that claim them to still be in spec. ;)
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Most doing it themselves find them out of spec, it is the stealerships that claim them to still be in spec. ;)
I don't see why the Dealership would have lied to me about the valve clearance being within spec.
He could have charged me alot more if they were in spec and He told me they were all out of spec and He
had to adjust them all. I went by the shop each day and I looked at the bike while He had it tore down so
I know that he did the work.
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Seems to me your story is one of the fairly rare ones where the dealer treats the customer right.
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Seems to me your story is one of the fairly rare ones where the dealer treats the customer right.
There are several posts on this thread where a dealer told them not to get it done at 15,000 miles. Seems a lot of honest dealers out there. I'll find out what my dealer says in 2,000 miles when I have to get it done. I just can't see them telling anyone not to spend money when the book calls for it.
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There are several posts on this thread where a dealer told them not to get it done at 15,000 miles. Seems a lot of honest dealers out there. I'll find out what my dealer says in 2,000 miles when I have to get it done. I just can't see them telling anyone not to spend money when the book calls for it.
A - Performing a valve check and adjustment involves removing/moving lots of pieces and parts, is time consuming and tedious, and ties up shop space that could be used for for quicker and more profitable jobs.
B - The job is spec’ed too low for labor hours, especially if the cams are pulled and shims replaced, and there is lots of opportunity for screw ups in the removal and reassembly of all those pieces and parts, so there’s more potential risk of a dealer further loosing time/money fixing things after the fact.
C – The risk to the dealer for deferring the job is low as “most” bikes will withstand the longer interval without damage (you all ARE getting it in writing that the dealer recommended NOT following the recommended service interval, aren’t you?). The risk to you may be greater, as you bought the bike with your money, you’re the one who will have to successfully make the case to get the warranty authorized if something bad results, and you’ll be without the bike between the time that something bad happens and it gets fixed and returned to you again.
D – Rationalizing that a dealer would not turn down your money may be incorrect if their perspective is that they’re minimizing losing money on this job by reducing the times it has to be performed.
In the end you make your choices and pay your money. The right choice *for you* is the one with which you are comfortable.
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Guess I'm a glutton for punishment. I can't wait to do it again. I think I had about as much fun tearing it down as I do riding it. Albeit it was down a long time the first time i pulled the 15K mx, but I've got the benefit of having it done once under my belt now, so should go quicker. I can't seem to remember off the top of my head, but think maybe 1 was in spec. Its documented here somewhere in this forum. I agree, it IS risky, but the Zen of it makes it worthwhile.
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..... Seems a lot of honest dealers out there. I'll find out what my dealer says in 2,000 miles when I have to get it done. I just can't see them telling anyone not to spend money when the book calls for it.
UMMMM, I think many of them are Honest to a point, but if pressed further thay may admit they had NEVER done one before, and this was the case for A LOT of dealers the first 3 years out with this bike....they simply did not have the clearcut methodology, or confidence in doing the job, let alone had they done any of them.... (even though the 1400Ninja was out prior, most never got high miles by the time the new Conni was released...and most didn't care to have them maintained by dealers either), so the dealers seemed to all be saying it didn't need it, or they pulled tha plastic off and put it back on, or maybe some did actually go thru the motions but said they "were within spec", because they didn't want to get hosed on the flat rate.
I believe there are still a lot of dealers out there that are actually afraid to tackle this job, and tie thier shop up till it's done, and they simply say it doesn't need to be done yet.
That being said, I had about 8-10 actual hours of "work" invested in mine the first go, but feel confident having the shim maps I made, I can accomplish everything second time in about 6 once I have shims. The key word is waiting for shims.... They time consuming part is actually mic'ing, and removing and measuring evrything the first time.
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Mechanical valve actuation, vs. hydraulic, permits higher RPM and, most importantly with an interference engine design, better control of the valves/less "float" at high RPM.
Do you "need" mechanical valve actuation on a S-T bike? No, but then you can't ever have too much power.... ;)
Goldwing's have hydraulic valves... ::)
The Goldwing has not used hydraulic valves since 2000 in the GL1500.
The 2001 and newer GL1800s' have mechanical valve adjustments, cam over buckets.
Honda calls for check and adjustment every 32,000 miles. Most are not out of adjustment at that time.
My 2002 GL1800 that I bought new has 166,000 miles on it. The first check was at 32000 and all was good. The first adjustment of 2 out of the 12 valves was at about 75000(and I only changed them to center like the other valves were). At 160000 almost all of the valves needed to be loosened up slightly (about .001). Still they were actually in spec but on the tight limit. All are now centered once again.
As you can see they really never changed very much and in my case could have been ignored for almost 200,000 miles without consequence. I do not plan to open the heads up again until around 225,000.
On my C14 I will most likely check the valves at around 20,000 or so. It will be just to make me feel good and safe even if they don't need adjusting.
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The Goldwing has not used hydraulic valves since 2000 in the GL1500. The 2001 and newer GL1800s' have mechanical valve adjustments, cam over buckets.
You're right, I should have specified I was refering to the 26 years before the 1800's that they were, from 1975 to 2000...
On my C14 I will most likely check the valves at around 20,000 or so. It will be just to make me feel good and safe even if they don't need adjusting.
I don't think that anyone who doesn't think they should check their valve's lash should do so.... 8)
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You're right, I should have specified I was refering to the 26 years before the 1800's that they were, from 1975 to 2000...
Then you still are missing the mark. The GL1000 and GL1100 used the old screw and locknut method to adjust the valve clearances. Goldwings did not have hydraulic valves until the GL1200 was introduced in 1984.
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Then you still are missing the mark. The GL1000 and GL1100 used the old screw and locknut method to adjust the valve clearances. Goldwings did not have hydraulic valves until the GL1200 was introduced in 1984.
Well damn, when I'm wrong I'm really wrong. I'll have to reflect more on my ancient history before making statements about which bike had what.
The only reason I mentioned GW's was to illustrate that hydraulic valve actuation has been commonly used but that it also has different physical limitations. Little did I realize I'd provoked the GW faithful to rally to defend their honor by doing so.... ::)
Thanks for the clarification!
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The only reason I mentioned GW's was to illustrate that hydraulic valve actuation has been commonly used but that it also has different physical limitations.
I think there is another limitation to hydraulic valves. In 1984, Honda also put hydraulic valves on a couple of Nighthawk models (I think the 550 and 650) and there was quite a discussion at that time about the need to keep the oil very clean and a shorter oil change interval to keep the hydraulic valves working as designed, especially at high rpms. I don't think that design was very successful for Nighthawks because those models were dropped after a couple of years.
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The nighthawks also suffered from poor sales since everyone wanted Honda Hurricanes at the time. At the time, the valve topic never came up.
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It isn't the type of bike that requires mechanical type tappets, it is the RPM range. Hydraulic lifters will not function properly at engine speeds over about 7K RPM and so would not work on a C-14. They tend to 'pump up' and get longer (easy boys!) and thereby reduce the valve lash until a valve hangs open.... the exact thing we are discussing here should a mechanical tappet (or solid tappet) go far enough out of adjustment.
Another problem with hydraulic lifters is that they are fairly tall- because the valves and cams are in-line on a C-14 (and most modern motorcycle engines), a taller lifter would result in a taller engine and therefore a taller frame. The actual height of thickness of the mechanical lifter currently used is really quite small- something like 1/8" or so.
And finally there is the additional cost. It is one thing to say that we would all pay more up- front for the motorcycle if the maintenance were less but in reality the price on the dealers' floor is what makes or breaks the deal. It is almost always impossible to justify a higher sales price based on some potential future savings.
Brian
Very good info here, but I still wonder why in this day and age of vast internal combustion technology does any engine need adjustable valves? As I understand it hydraulic valves produce less horsepower than conventional valve set-ups.
I can see where the squids and tuners would want the conventional set-up but why does a sport-tourer need it?
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The nighthawks also suffered from poor sales since everyone wanted Honda Hurricanes at the time. At the time, the valve topic never came up.
The Hurricanes were a vast improvement over the Nighthawks but they didn't hit the showrooms until 1987. I think the Nighthawks had been discontinued by then.
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The Hurricanes were a vast improvement over the Nighthawks but they didn't hit the showrooms until 1987. I think the Nighthawks had been discontinued by then.
1986 was the last model year for the Nighthawk, I believe.