4-Valve valve adjustment

I'm wondering what you do-it-yourselfers have done regarding valve adjustment on the 4-valve bricks? I've done it myself on the old 2 valve bikes; there was once a kit with spare shims circulating the community. The 4-valve bikes seems to require the PITA cam removal, but even once you accomplish that, do you just go to the dealer to buy the shim sizes you need?
The typical approach I've seen in scanning postings has been to ignore the issue altogether, and go on the theory that they never get too far out of spec. I've just measured mine (2003 K12RS w/ ~50k miles, never previously adjusted) and found all the exhaust valves in spec; three of the intakes were low. The worst was at 0.004 for a spec of 0.006-0.008.

Thoughts?

I'm going to lurk here on his question too... my son wants to do the same on his 96 K1100RS.

I did some further research after my initial posting.
There are some good online sessions on how to do the job. It doesn't look too tough. My big fear is having the cam chain slip a tooth and the timing going to hell.
My local dealer has the valve buckets in stock (most sizes) for about $35 each.
I'd still like to hear from those who have done it.

Unlike the 2V bikes, there are no shims so you have to install a new bucket. The service manual outlines the procedure for removing the cam. Once that’s out, you can remove the buckets one at a time and measure them with a micrometer, record the thickness, then calculate the size bucket you need to purchase to correct the clearance. Sometimes you luck out and can move an existing bucket to a new location to correct the clearance, and not need to buy a bucket. There is a chart in the factory service DVD that is useful for recording bucket sizes and calculating replacements or moves. But do always check the buckets with a micrometer, even tho their size is printed inside. The valve cover gasket can be re-used if in good condition, but needs a couple small dots of RTV at locations shown in the manual.

It’s not a bad or terribly difficult job, just be methodical about it.

Best,
DG

You've probably already seen this and since you've done it yourself a few times, maybe this doesn't help. It's for the K1200LT. The Illinois BMW Riders have some videos on checking the clearances...not sure what it says about what to do if things are out of spec:

https://illinoisbmwriders.com/servi...s/15-k-bikes/22-k1200lt-valve-clearence-check

4 valve valve check/adjustment

I viewed the video cited above and found it very confidence-inspiring; fortunate because I'm looking to check and maybe adjust the valves on my K1100LT soon. The one part that does give me pause however, is indexing the sprockets when it's time to install the cams once again. The video references a OEM tool but the guy doesn't have/use it when he replaces the sprockets. Mess that step up and you could cause yourself a serious headache $$$. My plan is to take a lot of pix as I go in there to measure clearances and possibly swap buckets.

walt3022 said:

I viewed the video cited above and found it very confidence-inspiring; fortunate because I'm looking to check and maybe adjust the valves on my K1100LT soon. The one part that does give me pause however, is indexing the sprockets when it's time to install the cams once again. The video references a OEM tool but the guy doesn't have/use it when he replaces the sprockets. Mess that step up and you could cause yourself a serious headache $$$. My plan is to take a lot of pix as I go in there to measure clearances and possibly swap buckets.

Click to expand...

Exactly my issue.
I'm okay with tying the chain to the cam sprockets and pulling the cams off of them, but what about going back on?
With the cams off the sprockets, and the chain tensioner backed off, what's keeping the chain engaged properly with the crankshaft sprocket? If a tooth slips there, what do you do?

Unless you’re really manhandling the chain that shouldn’t be an issue. Make sure you use good quality small zip ties on the cam sprockets, and at least two per sprocket.

Best,
DG

Update: Inlet cam is out. Measured the three buckets I need. Dealer doesn't have the right size in stock so the job waits.

All relatively easy so far, but the proof is in it's running when back together. Remounting the sprocket on the camshaft looks to the challenge. Time will tell.

Can you give us more details? How many miles are on the bike? Do you know when the valves were last checked? Did you find any marks on the sprocket and camshaft to aid in putting them together? Do you need to adjust both inlet and exhaust valves?

walt3022 said:

Can you give us more details? How many miles are on the bike? Do you know when the valves were last checked? Did you find any marks on the sprocket and camshaft to aid in putting them together? Do you need to adjust both inlet and exhaust valves?

Click to expand...

Sure, Walt.
Most of questions were addressed in my initial post. 2003 K12RS w/ ~50kmiles. I've had it since about 10k miles, so I'm pretty sure the valves were never checked nor adjusted.
I've now found three of the intake valves under spec. All the exhaust valves are within.
With the exhausts good, I've only pulled the intake cam. That cam's sprocket is the only one I've taken off.
A hole in the center of the sprocket slides over the end of the camshaft, held on by a bolt that threads into the center of the camshaft. The proper alignment of the two (timing) is assured by a pin that is permanently pressed into the face of the sprocket, protruding on the cam side of the sprocket. The camshaft has a groove machined on the edge of it's end face that allows the two to go together only one way (the pin goes into the groove).
I assume the exhaust cam is done the same way, but since I haven't taken it apart, I'm just guessing.
Only other thing I've noticed is about the hex that is cast into the camshaft. It's there to allow the shaft to be held from rotating while the bolt holding the sprocket on the end is torqued. Since it's an as-cast hex (not machined) it's size is not exact. They call it a 19mm hex, but it's smaller, meaning a 19mm open-end is oversized. I hate using wrenches that aren't a good fit on any hex as they tend to round the hex off. I haven't found a wrench that's a good fit. When it comes time to reassemble the cam/sprocket, I may try using an adjustable, just to get a better fit.

Thanks for that update. I think it's very interesting that the valves that need attention are the intakes. Exhaust valves run hotter, and it's been my experience that they often are the ones that require adjusting.
I bought a K1100LT with a mere 22 K miles on the clock last year. No real history came with the bike so I'm assuming the valves have never been touched. I will measure them soon, and I expect I'll be shopping for valve buckets too.

FWIW, not only is it only intake valves that need reshimming, but curiously, all three are the righthand valve (when viewed from the bike's right side) of the two intake valves. Not sure if that means anything or is just a coincidence.

On another note, I decided to add a new valve cover gasket as part of my reassembly, rather than risk oil leaks after it's all buttoned up. The new gasket costs $80! For a friggin gasket! Had I known I'd have planned to RTV the old one and reuse it.

More important for preventing leaks at the V/C are the rubber bolt bushings. Since the bolts have a shoulder that bottoms out during installation, it is the resiliancy of the bushings that puts the pressure on the V/C and gasket. The gasket is usually good for many valve checks without replacement, but the bushings get hard and don't put correct pressure on the gasket causing leaks.

The bolt bushing for the 4 valve Bricks is 11 14 1 461 475 ($3.61) You need 11 of them. 2 valve Ks take a different (and cheaper) bushing.

You will need a few tiny spots of RTV anyway, at the locations specified in the manual. Those dots are to help seal the sharp internal corners of the gasket at the hump. RTV anywhere else on the gasket will just create leaks. Those rubber gaskets can be re-used many times.

Best,
DG

Job complete!
Today I put in the new buckets to set the valve gaps, and buttoned the whole thing up. Problems I was concerned with turned out to be non-issues. The chain never slipped off the crank sprocket, and the one cam sprocket that I did remove (intake) was easy to get back on the shaft.
I never really felt like had moved the cam chain tensioner, which is required in order to get enough slack in the chain in order to get the sprockets off. But apparently either I did, or since the bike had been sitting a month prior to the job, the oil had drained from the tensioner and it retracted itself.
As mentioned previously I went with a new valve cover gasket. FWIW, the new one measured 0.020" thicker than the old one, which had been compressed in there for 16 years. I didn't use new rubber spacers on the valve cover bolts because 1) I didn't remember to buy them when at the dealer, and 2) after spending $250 on this job, I cheaped out. I'll watch for leaks.

Of course now I have mastered this new skill, but it's on a bike that may never get its valves adjusted again. So if anyone's riding their K thru Western Mass and feels the need for a valve adjustment.....

Congrats, and enjoy the ride!

Best,
DG

valve cover removal

GTRider said:

Congrats, and enjoy the ride!

Best,
DG

Click to expand...

I wish I could say this job is behind me. I began to remove the lower fairing this afternoon, as we have a period of very mild weather now. I now wonder (with the lower fairing bit loose but still in place) if there is enough wiggle room between it and the valve cover to pull the cover off with the fairing piece still in place. Has anyone done that?
Second question: what's the trick to removing the black plastic cover from the upper part of the tipover bar? Mine seems welded in place? I'd rather not destroy it....

walt3022 said:

I wish I could say this job is behind me. I began to remove the lower fairing this afternoon, as we have a period of very mild weather now. I now wonder (with the lower fairing bit loose but still in place) if there is enough wiggle room between it and the valve cover to pull the cover off with the fairing piece still in place. Has anyone done that?
Second question: what's the trick to removing the black plastic cover from the upper part of the tipover bar? Mine seems welded in place? I'd rather not destroy it....

Click to expand...

Never tried it, I always remove the fairing side panels and the belly pan when doing a major service. I’m not sure what tipover bar you are referring to?

Best,
DG

I'm with DG. I'm not sure what a tip over bar is. Any chance you have a K1200GT (with the rubber fairing extensions)?

FWIW, once the belly pan is off, there aren't that many more screws to pull in order to get off the left side panel. Okay, now that I rethink that, there are a ****load of screws because the "dashboard" panels on their side of the instrument pod have to come off along with the nose piece.
Put a positive spin on it: it'll give you the chance to check the other components for signs of wear and fraying. I'm taking the opportunity to change the air filter and coolant since I'm already in there.

Come to think of it, has anyone else had paint bubble forming on the crankcase cover? One is about 3/8" diameter, and other a full 1 1/4". The paint lifts off the magnesium cover and swells up to form a full round, hollow bubble.