DIY valve clearance check/adjust

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...I'm surprised the dealers don't keep a good supply, they must get bikes in for this job on a regular basis.
The joy of living in a small town and a dealer who would rather sell boats and snowmobiles. The shims aren't all that hard based upon the relative ease of sanding starting with 320 grit paper so I don't think there is any special surface treatment. If I thought I would be in big trouble, I would order the shims now and swap them as soon as I got a chance. 5 hours or so of work to swap them vs the (small) potential for a damaged motor.

 
The problem wasn't paying for the shims. The problem was getting them once it was determined what I would need. Dealer didn't have them in stock and they would be three days away if I ordered them. I'm pretty sure they aren't case hardened.
I just wish that every engine that has shim under buckets would come from the factory with an initial shim map so you know what's in there before you remove the camshaft(s). That way, you could determine the replacement shim first, then go get 'em, then remove said camshaft(s), replace shim(s), re-install camshaft(s) without stopping.

Dan

 
bergmen

Since I read your post about shim sanding, I did a bit of searching for Internet "wisdom" on the subject! Let's just say the topic has been heavily discussed and opinions vary from "I do it all the time with no issues" to "don't do it or I guarantee that you will destroy your motor". It seems that most of nay-sayers are not speaking from direct experience and evidence is, at best, anecdotal or theoretical. In my limited search, I didn't come across any instances of shim or bucket failure for a shim-under-bucket setup that could be attributed to a sanded shim. Again, some opinions suggested that the shims are case hardened and removal of this layer would allow the shims to cup or mushroom; maybe even break. (Given the relative ease of material removal, I seriously doubt that these shims are case hardened) There is no shear load with the Yamaha bucket design - cam lobes ride on the bucket, not the shim. There is compressive load from the valve stem but the contact area is a small fraction of the surface area of the shim.

Despite the fact that I have not read anything that shows that there is a real problem with the process, on my next check (likely this winter), I think I will pre-order enough factory shims to replace all of the intake shims whether any of them are out of spec or not. I'm not particularly in the mood to re-do everything now. For the sake of furthering the knowledge on this forum, I will be sure to document the physical condition of the sanded shims after removal. At least I documented the after-sanding dimensions so I can reasonably predict the thickness needed for the replacement shims. Again, the shim sanding had nothing to do with cost saving. I simply did not want to leave everything open for several days while waiting for receipt of new shims; especially during good riding weather.

In the meantime, the bike is running great with over 110,000 miles on it. Just as much power as the day I got it and doesn't burn a drop of oil.

So, does anyone have any experience with problems associated with sanding valve shims? Perhaps I will be the first with a grenaded engine or photographic evidence of whether or not the practice is safe.

 
Ross, you're fine. If those shims were case hardened, all that paper would have done was scratch them and you would have known something was up.

Remember, we're supposed to trick FredW into taking his motor apart, not you!

 
I'm just speaking from my personal background experience.

My Dad was a machinist/millwright from the 1930s, made it to the Lockheed aircraft tooling department (called the jig shop) before WWII. Worked through the war and retired in the late 1970s. He had "the touch" and taught me and my brother well from the day we were old enough to hold tools in our hands (earlier than I can remember). From that perspective, I would be afraid to do what you did. That does not mean that you caused any problems, I'm only looking at this from my schooled perspective.

It will be interesting to see what you find when you do another check. I will be interested in your report.

Dan

 
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I doubt the shims are case hardened. The cam rides on the buckets so the buckets would be case hardened. The shims are just spacers between the buckets and the valve stems with no relative movement between parts.

 
I doubt the shims are case hardened. The cam rides on the buckets so the buckets would be case hardened. The shims are just spacers between the buckets and the valve stems with no relative movement between parts.
This is what happens when I talk out of my arse!

You are correct, there would be no need for the shims to be hardened. My last bike was a Yamaha Venture Royale. That engine has "shim over bucket" and the cam lobes ride on the shims. The advantage is that the shims can be changed without removing the cams.

 
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Hi Folks,
Well I have put 16k miles on my new-to-me FJR since Feb and she is sitting at 28k miles. So I am planning to check the valve clearances in the near future. I am not willing to pay the $630 + parts + tax the dealer wants. I have free time now since I am between jobs and I would enjoy doing it.

I do not expect anyone local that is experienced in this to have the time to look over my shoulder. But it might work if someone is going to do their valves and I can look over their shoulder and help where I can. I will then be comfy to come home and do my own I think.

So question 1
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: Anyone within a few hours of Olympia WA planning to do their own valve check in the near future?

Option one is a long shot so I might be on my own. But I do know it would not be wise to just start tearing the bike apart per the service manual. One little detail missed would be bad. So the plan is to study the posts on the topic and put together a doc to guide me. These seem to be several posts, but nothing comprehensive. Maybe I missed it.

Question 2: Has anyone put such a doc or post together that I could us as a reference?

This forum is great and I am sure once I get started and share on the forum what I am doing, someone will point out if I screw up at any point in the process.

Thanks!
Just finished a valve check on a forum members bike last week (KBacon). He had 34,720 miles on his 2007, and no adjustment needed! I have the TBS "tool" (Motion Pro Sync Pro), and an extra head cover gasket (which you probably won't need), and all other tools. I also have a shim kit. However you'd have to ride through eastern WA, and probably ride Highway 12 and Lolo Pass to get here. That would probably suck....................

Also, you might have to buy 2 O rings.

Anyway, come on over, and we'll check your valves. No worries!!!

 
Hi Bob,

That is a great offer and I am definitely considering it. I was thinking of doing a trip to Hells Canyon and I could just keep going :)

Will say July 17th work for you?

Henry

 
Henry

July 17 could work! Remember the check needs to be done on a "cold" engine, so you'll probably want to spend the night before the check in Salmon, so your engine is relatively cool when we start to "tear into it". Just keep me posted via a PM!

Bob P

 
Valve shims 101

I have a unique perspective on this subject as I was a surface grinder for about 19 years. I worked with all types of both hard and soft steels. I needed to know a good deal about steel: how it performed under stress, why it bent, broke, dulled, or mushroomed - and what type of steel to choose to get the job done. I have read this thread carefully and I'd like to try to help just a little.

Making and grinding shims:

I made a couple shims for my 78 Suzuki GS1000 out of A2 tool steel. I ground several shims for a Kawasaki KZ1000 (about the same year) as well. When I made my Suzuki shims, I hardened them in the shop to about Rockwell 55 and ground them on my surface grinder to the required thickness. They worked just fine. While I was doing that particular valve check, several shims needed to be ground. I checked them carefully for hardness before and after grinding. There was no change. I wish I could remember how much I took off the 4 or 5 shims that I ground, but I'm thinking it was no more than 5 thousandths of an inch. Not long afterwards, I did the same on the Kawasaki shims. No issues or problems with changes in hardness after grinding.

Grinding vs. Sanding

You will not get them hot enough to cause them to lose their hardness. Steel has to get really hot (think: cherry red) to affect its hardness. What I did on a surface grinder can easily be done by sanding, it's just a lot slower.

Case hardened or hardened all the way through?

Wish I could answer this. Tool steel that hardens all the way through because of its high carbon content is $$. Low carbon steel that has to be case hardened is cheaper. But case hardening costs more. Which would a manufacturer choose? Wish I could answer that...

Depth of case hardening

I would seriously doubt that even if valve shims were indeed case hardened, that the hardness could be less than 5 thousandths deep. I would not have any fears of removing that much by sanding.

Accidentally sanding them too much on one edge

This could cause the upper and lower surface of the shim to be out of parallel. One edge would measure larger than the other. You are very unlikely to do this if you are aware that it can happen. Clamp down lightly on the shim in the center of a bench vise with a piece of sheet metal to protect each end. Spin the shim with your fingertips. If it spins smoothly, you're good to go. If it binds on one edge, you'll know that the flat surfaces are not parallel. You will indeed be able to feel if your sanded surface is out of parallel. However, it his highly unlikely that this will happen if you take a little care in sanding.

Hope that helps.

Gary

darksider #44

 
The valve shims are not hardened at all. The biggest manufacturer of aftermarket shims (Hot Cams Products, Inc.) says they use 4140 cold rolled steel (with no hardening), and I do not see why anyone else would harden them either, for this application. As was mentioned, due to the way these shims are situated underneath a cam follower bucket (which is, without a doubt, hardened) there is no need to have the shims hardened. These are merely spacers.

In the case of the much larger (29 mm diameter, 2 - 3mm thickness) valve shims used on my old BMW K100RT brick engine, the cam lobes directly bore against the top of the shims in that engine. There the shim rides on top of the bucket, so those shims need to be hardened. You would be sanding those shims for a very long time before removing any appreciable amount of material. This may be where some of the misconception about all shims being hardened comes from. It depends on the shim application.

Now, if they actually were case hardened, and you were actually able to sand away some material, that hardening process typically penetrates the surface of the steel by at least a full millimeter, generally penetration is considered to be about a millimeter and a half. I don't know how much Ross reduced his shims, but mine required only 0.06 - 0.08 mm of reduction to put the out of spec too tight clearances up to the wider side of the spec range. IOW, less than a tenth of the thickness of case hardening.

I also sanded my shims when they needed to be adjusted, and like Ross mentioned , they reduced in size quite easily using a very fine paper and only fingertip pressure. As for getting the sanding parallel it is quite easy to do using just even finger tip pressure, lapping the shim on a flat surface, and can easily be verified with your micrometer measurements as you go.

However, being off parallel a small amount (you are only removing a small amount to begin with) really would not matter very much as long as the center is the right thickness. That is because only a small part of the very center of the shim is in contact with the bottom of the shim bucket. There is a small diameter raised area on the underside of the bucket that physically contacts the shim.

I would not worry in the least about your sanded shims, Ross. Just check them again when it's due and make adjustments only if they are actually required. My bet (and I'm betting with my own engine as well) is that they will not.

 
What are the recommended materials needed for sanding the FJR shims? I may give it a try.

A simple step by step fingertip procedure please.

I have a micrometer so I can easily measure the before and after thicknesses.

 
Well, there you go, two excellent and authoritative posts by Gary and Fred. I certainly learned something today and this is great info.

4140 is tough steel and I can see that there would be no need to harden shims that are not exposed to any surface wear (as shims on top would).

Dan

 
What are the recommended materials needed for sanding the FJR shims? I may give it a try.
A simple step by step fingertip procedure please.

I have a micrometer so I can easily measure the before and after thicknesses.
Other than a micrometer and the knowledge of how to use it, you will just need a flat surface to work on, a bunch of relatively light grit sand papers, and a bucket load of patience.
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I opted to do mine dry because I had a bunch of finishing sandpaper on hand, but another option would be to use wet or dry paper, which would allow you to do the sanding wet and allow the paper to last longer without getting clogged up.

Ideally, you'll want several sheets of a couple of different grit papers. One slightly more course to help you remove the material faster, and then a finer paper to get the last little bit, and leave a more polished surface. I used 240 and 500 grits finishing paper as that is what I had on hand, and those seemed to have worked well.

I recommend sitting down and making all your initial measurements, calculations, and determine your target new shim thickness measurements in advance. You'll probably need to do some calculating back and forth between metric and imperial unless you have a metric micrometer (mine isn't).

You can lay out a full sheet of sand paper on your flat surface and then tape the corners down so it doesn't shift around on you. Place the shim flat on the paper and just using your finger tip on top of it, slide it around on the paper in a circular or figure 8 pattern with gentle pressure. Turn the shim under your finger every so often to insure you get even sanding across the face of the shim. Check the thickness more often than you think necessary. It is awfully hard to put material back on the shim if you go too far.
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Just before you get to the target thickness, switch to the finer paper. What you'll be doing is knocking down the microscopic ridges on the surface of the metal left by the courser paper and leave a more stable surface. Otherwise the shim thickness may actually shrink a tiny bit as those ridges get compressed and flattened during use.

That's pretty much it. Just come up with your own system to keep track of which shim came from where, take your time and try hard not to overshoot your targets by too much or else you will be buying shims after all.
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Couple of thoughts:

1) A sheet of window glass makes a fine flat surface. Also a kitchen table with Formica top is pretty flat also.

2) Kerosene makes a very good wetting agent. Plus you will smell like a genuine gear-head when you are finished and ready to stink up the house (my wife hates the smell which is why I use it all the time).

Dan

 
One other thought:

Sand the side with the size etched into it. If you are going to reduce the thickness then you don't want the label to be misleading for the next poor soul who ventures into this area of maintenance on 'your bike'.

Truth in advertising and such.

Brodie

;-)

 
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