Valve Shimming - Look Like My Luck Has Run Out

I'm at 75k miles. THere is a dusting of snow on the streets and it's a Saturday that I have nothing much planned. Time to check the valves on the Feej. The last two times I checked them, all of he clearances wee good. Always on the tighter end of spec, but definitely good to go.

Unfortunately, try as I might, I couldn't manage to jam a .006" feeler gauge under the intake valves this time. Boo Hoo! I tried to convince myslef that .005" would be OK for another 25k miles, but if I lunched my valves because I was too lazy to adjust them I would never be able to forgive myself.

All of the Exhaust valves are still good at a loose .008" (can barely still get a .009 in there), but every one of the intakes has closed down enough to require reshim. The prior two checks they were all at .006" with varying degrees of tightness. Now they are all at .005 with the same vary degrees.

I've bit the proverbial bullet and decided to go ahead and adjust them in to spec, so I now have my cams tywrapped to the chain, the tensioner slacked off, and the intake cam and shims are all out. One thing I found is that the shims, after 75k miles, no longer show any markings of what they once were. I can see they were ink marked at one time, but the print is now completely illegible. No problemo... 'cause I got me a micrometer. After measuring the shims I was pretty surpised to find the shims were all so close in thickness. I guess that says a lot about Yamaha's manufacturing tolerances, eh?

All of my intake shims are either 1.79, 1.80 or 1.81 mm. Since they are all too tight now, and the shims are only available in .05mm increments, that says I'll need 8 new 1.75mm shims. I think I may investigate getting Honda shims as I understand they come in smaller increments and will allow me to fully exercise my anal retentive mechanical creativity, and place the new clearances precisely in the middle of the spec range. Hey... why not?

Follow-up to come

Fred W said:

I'm at 75k miles. THere is a dusting of snow on the streets and it's a Saturday that I have nothing much planned. Time to check the valves on the Feej. The last two times I checked them, all of he clearances wee good. Always on the tighter end of spec, but definitely good to go.

Unfortunately, try as I might, I couldn't manage to jam a .006" feeler gauge under the intake valves this time. Boo Hoo! I tried to convince myslef that .005" would be OK for another 25k miles, but if I lunched my valves because I was too lazy to adjust them I would never be able to forgive myself.

All of the Exhaust valves are still good at a loose .008" (can barely still get a .009 in there), but every one of the intakes has closed down enough to require reshim. The prior two checks they were all at .006" with varying degrees of tightness. Now they are all at .005 with the same vary degrees.

I've bit the proverbial bullet and decided to go ahead and adjust them in to spec, so I now have my cams tywrapped to the chain, the tensioner slacked off, and the intake cam and shims are all out. One thing I found is that the shims, after 75k miles, no longer show any markings of what they once were. I can see they were ink marked at one time, but the print is now completely illegible. No problemo... 'cause I got me a micrometer. After measuring the shims I was pretty surpised to find the shims were all so close in thickness. I guess that says a lot about Yamaha's manufacturing tolerances, eh?

All of my intake shims are either 1.79, 1.80 or 1.81 mm. Since they are all too tight now, and the shims are only available in .05mm increments, that says I'll need 8 new 1.75mm shims. I think I may investigate getting Honda shims as I understand they come in smaller increments and will allow me to fully exercise my anal retentive mechanical creativity, and place the new clearances precisely in the middle of the spec range. Hey... why not?

Follow-up to come

Click to expand...

Can you post some pics for those of us who have never adjusted valves?

I'll try to take some in the coming days (when I get my new shims), but there are already some very good tutorials online about doing this, and the checking part I have posted already in the past.

Fred W said:

Unfortunately, try as I might, I couldn't manage to jam a .006" feeler gauge under the intake valves this time. Boo Hoo! I tried to convince myslef that .005" would be OK for another 25k miles, but if I lunched my valves because I was too lazy to adjust them I would never be able to forgive myself.

All of the Exhaust valves are still good at a loose .008" (can barely still get a .009 in there), but every one of the intakes has closed down enough to require reshim. The prior two checks they were all at .006" with varying degrees of tightness. Now they are all at .005 with the same vary degrees.

* * *

All of my intake shims are either 1.79, 1.80 or 1.81 mm. Since they are all too tight now, and the shims are only available in .05mm increments, that says I'll need 8 new 1.75mm shims. I think I may investigate getting Honda shims as I understand they come in smaller increments and will allow me to fully exercise my anal retentive mechanical creativity, and place the new clearances precisely in the middle of the spec range. Hey... why not?

Click to expand...

Fred, are you sure the decimal point is in the right place in all measurements you've posted here? If you're looking to increase the lash by .001 to .003 mm (one to three thousandths), how can that be done by changing shims graduated in .05 mm increments (five hundredths)?

I've not done a shim under bucket valve adjustment on the FJR (but used to do shim OVER bucket systems on 4 cylinder motorcycles years ago), so I assume that there's no leveraged ratio at play here. So, I'm confused. Wait -- maybe you're intentionally mixing inches (") and millimeters (mm)? Shit -- now I'm REALLY confused.

You can try these......

https://www.rockymountainatvmc.com/p/43/53/210/922/-/26634/Pro-X-Valve-Shim

https://www.jakewilson.com/p/53/90/388/1280/-/26634/Pro-X-Valve-Shim

Just saw a post about a new 07ae for a good price.....maybe you should look into that.

There they are Ray. I knew they could be bought that way, because someone posted them last year, but I couldn't find them.

Fred, instead of shooting for the middle of spec I went for 3/4, or to the loose side to alow for more miles between shimming, and the engine will think the cams are smaller (in theory) and have more low end (not that you would notice). On the intake .006"-.009", I set to .008" and Ex; .007"-.0010" set to .009"

Sometimes I wish I was still running a surface grinder. I spent years in tool and die before becoming a teacher. I could have custom ground those shims to whatever length you wanted. Piece of cake to hold any size to +or- .0002 (of an inch)... I reground shims several times while doing valve adjustments years ago. Interesting thing about grinding. You can tell approximately how hard a given piece of steel is by the color of the spark, and to a lesser degree, by the sound as you grind it. Shims, oddly enough, were easier to grind than many of the tool steels I worked with. Like the sine plate below, for example. It's much more difficult to get it dead STRAIGHT than it is to get it to an exact size.

EDIT: For WIW, I checked the shims for hardness before and after grinding them, just to be sure: no change was detected. Surface grinding doesn't affect the hardness of metal unless you get it seriously hot, or unless you grind through the case hardening, which is typically NOT the way factory shims are made... they're usually hardened through. While I was at it, I made one shim from scratch using A2 tool steel hardened all the way through to the same hardness as the rest of the shims I was working on for a 78 Suzuki GS1000. Interesting discussion on grinding/making valve shims occurs here: CLICKY

I don't have many pictures around of the work I did in those days, but I did have one of a 6 inch sine plate I built. Most of this was finish ground on my surface grinder. You can see that the finish quality produced by these machines is amazing.



Gary

I'll be following your trials here Fred. We've been lucky with valve checks in the PNW but one of these days... the luck will run out.

Single shim looks to be a good way to go if you have time, otherwise a kit from https://www.rockymountainatvmc.com/p/43/53/210/922/-/10839/Hot-Cams-Valve-Shim-Kit Hot Cams might be in my future.

Good luck and let us know the [ugly] details.

--G

road runner said:

There they are Ray. I knew they could be bought that way, because someone posted them last year, but I couldn't find them.

Fred, instead of shooting for the middle of spec I went for 3/4, or to the loose side to alow for more miles between shimming, and the engine will think the cams are smaller (in theory) and have more low end (not that you would notice). On the intake .006"-.009", I set to .008" and Ex; .007"-.0010" set to .009"

Click to expand...

This guy road runner appears to have outlined the path that I would take if I was facing re-shimming. I do not have the details before me about resurfacing the shims & would want to inquire about any surface hardening or if they were only dumb shims.

Re-shimming appears to be one of those tasks that has the degree of appeal that puts yet another smile on your face Fred, have fun with it & keep us posted.

As always, pix are appreciated.

exskibum said:

Fred W said:

Unfortunately, try as I might, I couldn't manage to jam a .006" feeler gauge under the intake valves this time. Boo Hoo! I tried to convince myslef that .005" would be OK for another 25k miles, but if I lunched my valves because I was too lazy to adjust them I would never be able to forgive myself.

All of the Exhaust valves are still good at a loose .008" (can barely still get a .009 in there), but every one of the intakes has closed down enough to require reshim. The prior two checks they were all at .006" with varying degrees of tightness. Now they are all at .005 with the same vary degrees.

* * *

All of my intake shims are either 1.79, 1.80 or 1.81 mm. Since they are all too tight now, and the shims are only available in .05mm increments, that says I'll need 8 new 1.75mm shims. I think I may investigate getting Honda shims as I understand they come in smaller increments and will allow me to fully exercise my anal retentive mechanical creativity, and place the new clearances precisely in the middle of the spec range. Hey... why not?

Click to expand...

Fred, are you sure the decimal point is in the right place in all measurements you've posted here? If you're looking to increase the lash by .001 to .003 mm (one to three thousandths), how can that be done by changing shims graduated in .05 mm increments (five hundredths)?

I've not done a shim under bucket valve adjustment on the FJR (but used to do shim OVER bucket systems on 4 cylinder motorcycles years ago), so I assume that there's no leveraged ratio at play here. So, I'm confused. Wait -- maybe you're intentionally mixing inches (") and millimeters (mm)? Shit -- now I'm REALLY confused.

Click to expand...

.05 mm = 0.001968504 in

Or about .002 in per increment in shim size

Thanks for all of the replies. And sorry for the confusing prior post. I was mixing metric and inch based measurements in that.

In my first two valve clearance checks I used inch based feelers, with the idea that I needed to pass an .006" gauge in to be good on the intakes, and an .007 in on the exhaust as a "go". This time the .006's wouldn't go, so I switched to metric to get a closer idea of where I actually am. Metric feeler gauges are a finer gauge.

On the metric scale, all of my intake valves were between .12 and .14 mm. The spec is .15 to .22 mm. If it weren't for the one valve that was .12, I might have let them all go another 25k mile round, but that one seemed just a bit too tight to let it slip. I don't want to start burning valves.

As for spoiling the hardening of the shims by sanding or grinding, I'm not sure that really matters all that much. The shim is underneath the bucket, which takes all of the wear and tear from the cam. If I thought that I could accurately reduce the existing shims by the appropriate thickness, I sure would be tempted to do so.

I actually helped Yamafitter with his most excellent shim calculation spreadsheet, and that does set the shim to the looser side of spec for the reasons that Art mentioned (prolonged reshim). But if the shims are only available in .05mm increments that point is kind of moot. You pick the best fit and go.

OTOH, if the Honda or other aftermarket shims can be had in .01 mm increments, then I'm all over that.

The last time around on mie I needed to change two exhaust shims. The dealer assured me they had shims . Wrong. I lapped two shims on a surface plate and it took over two hours and a lot of measuring.

If you can buy the right ones it's well worth it.

I'm thinking that when I finally get my ass in gear and dio this, I'll get a shim kit and a new CCT and be in and out same day

Hey Fred,

Is it possible to request the parts list required to do the valve check? It is my understanding the seal for the valve cover itself is re-usable, but I know there several smaller pieces needed (like o-rings and such). Figured this would be fresh info since you are into you check. I have looked back through some of the past threads and checked the Bin O’ Facts area and have not been successful in finding a parts list for our GEN-1 rides. A valve check is in the cards for me while I’m off for the holidays later this month along with fluid changes. Maybe we can even get one of the admins to add it to the Bin O’ Facts (once they get past the dust from this upgrade). Thanks for all your contributions to the group. Your efforts are greatly appreciated.

George

Just curious, what are shims selling for these days anyway?

Gary

darksider #44

Fred W said:

the shims are only available in .05mm increments,

Click to expand...

Fred W said:

But if the shims are only available in .05mm increments that point is kind of moot. You pick the best fit and go.
OTOH, if the Honda or other aftermarket shims can be had in .01 mm increments, then I'm all over that.

Click to expand...

The smallest I've ever seen is .025mm increments. Pro-X brand at jakewilson.com. Don't have to buy a whole kit, they're sold by the piece.

Well, this little maintenance is over now for me. Reshimmed all 8 intake valves to the loose end of spec so (hopefully) I will never have to do it again, at least not for the intakes. The loose end is the safer one to be at. Nobody ever lunched their engine from the valves being too loose.

I have a few observations that I will share. As for a complete procedure, you really can't beat this one done by Dwayne Verhey many moons ago for a step by step complete with pictures. My tips below are a few things that he doesn't cover or ideas I came up with on my own.

Once you get access with the valve cover off, you can make your clearance measurements and decide if reshimming is required. In the past, I have always been able to get a .006" feeler gauge comfortably in to the Intake valves, which have always been on the tight end of spec, but this time.. no such luck. So a reshim was required.

Once you decide to reshim, you will need to take some precautions to be sure that you are able to get the engine re-timed correctly after slackening the timing chain. As I'm sure you have all heard, messing up the valve timing by more than a tooth can be disastrous to your engine when the pistons smash the still open valves, and your previously effective, high performance 1300cc lump will instantly become a boat anchor.

Here's a picture of two things I did to help in that regard. Before even slackening the chain, I set the engine at TDC on #1, which can be signified by the green arrows on the right end of the crankshaft here:



Line up the T- mark with the split in the cases. Double check that the two cams for #1 are splayed outwards away from each other (as when you checked the clearance) and you are at TDC compression of number 1. Do not move anything from here until you are confident that you have the timing correct again.

I also Ty-wrapped the timing chain to both cam sprockets



This ensures that the timing between the two cams will be maintained, but does not guarantee the timing between the two cams and the crank will be correct. For that you will need to pay extra attention, since there is no way to secure the chain to the crank sprocket (that I could find).

If you look closely at the above photo, you can also see that I have marked a dot with a sharpie marker on the joint between each of the cam shafts and the cam cap brackets while the engine was at #1 TDC (before slackening the chain). This is the most valuable mark you can make because the dimples in the back side of #4 cam lobes (also in the picture) are too far away from the arrows to be useful, and you sure can't see the arrows on the cam sprockets next to the frame.

Now, it's time to slack the tensioner.
A few years back I upgraded my stock CCT to one of the new and improved "blue dot" variety. The only problem with that was that the new tensioners do not seem to have a "detent" at the fully retracted position. Since you need to hold the chain fully slack while yanking the cam out, this presented a problem. My solution (look back to the red arrow in photo #1) was to use some hemostats to clamp a screwdriver in place after fully winding the tensioner. It worked OK, even overnight, which was really nice since the alternative was to remove the CCT entirely.

With the cam chain ty-wrapped in place, you can't fully remove the cam, but you can lift it and move it aside enough to do the deed. Here's a picture of the intake cam set forward enough to get at the shims. You'll also notice that I have the "buckets" off and have removed the shims except in 1A 1B and 2A



So now we get to the crux of the biscuit...

As for having a "shim kit" on hand, in my experience it would not have helped much. The shims in the various kits, as well as any replacement shims from Yamaha, come only in increments of .05mm. The vast multitude of the shims (that you pay so much money for) in those kits are completely useless on any FJR. Also, the kits only provide 3 of each particular shim size in the kit.

In my case I needed to replace all 8 of my intake shims. The originals were all between 1.79 and 1.81 mm, so the next size down is 1.75. Therefore I would have needed 8 of those 1.75's and would have been 5 short even if I had a kit on hand. For $80? Save your money.

Instead, you could buy 8 or 10 in a few select sizes and you should be in better shape. For intakes I'd say get 1.70's, 1.75's and 1.80's I don't know what sizes are typical on the exhaust side because mine are still well within spec.

Buying 8 shims at the local stealership was going to be an expensive option. They want $5-6 each, so it would have cost me $40-50 for 8 little pieces of metal. Being a tightwad cheapskate, I opted to sand the old shims down to spec instead. This requires that you have (and know how to use) a micrometer.

Either way, you'll want to make the initial clearance readings in millimeters, as this gives you a finer measurement than inch based feelers. Then use the most excellent Yamafitter shim calculation spreadsheet to calculate what thickness the new shims should be.

Here's a screenshot of my spreadsheet:



As you'll notice, my initial clearances were all just barely substandard. This gives me a warm fuzzy feeling that my engine overall is healthy and is wearing "normally" (whatever that is).

The shim thicknesses were all measured using a micrometer (in inches) and then converted to closest metric. Likewise the metric recommendations for shims were back converted to inches for use with my micrometer as I shaved down the old shims with sandpaper.

I'm not saying this kind of torture is for everyone... but I was able to get each of my shims into the target of .20mm clearance within +1 and -0 mils. That's not too bad for a guy with sandpaper on a kitchen table. My fingers are a bit tender today, but there was no bleeding. And the shim sanding on all 8 shims only took only about an hour and a half. Much of that as because I used 240 grit paper to reduce the thickness and much finer paper to polish the finish.

So there you have it. I've probably;y already forgotten some of the good ideas I came upon during the experience, but hey... that just leaves more fun for you!

Great write-up, Fred! Thank you.