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2001 K1200 RS Valve Clearance Question?

weschmann

Kawa Afterthought
I've just completed my annual valve clearance check (47000 miles and found the exhaust valves to be at the tighter end of the specifications, at around .254mm. Clymers' spec's state the exhaust should be between .25 to .30mm, so I'm at the tighter end of the spectrum. Intake valves were all dead center of spec. at .178mm. All 4 exhaust valves came in at this tighter spec., so my question is, should I have them adjusted at the dealership now, or wait another 12000 miles and check them again? at .254, the feeler gauge slipped very easily in the gap, so they may be a bit looser than the .254, but the next gauge I have at .279 was too tight, so there has been a change from the last time, at around 25000 miles when I checked them.

It should be noted that I am competent enough to check the valves for clearance, but have doubts about my ability to remove the cams (actually, I'm pretty sure I can get everything apart, but not so sure that I can stick everything back together again, at least not without a couple of extra parts left over that I'll have no idea where they go) :-(

Also, when removing the spark plugs, I found that #2 cylinder from the back of the bike where the spark plug wire clips on to the spark plug, to have quite a bit of light white dust inside the spark plug wire, which looked like it may not have been real tight to the spark plug and got hot. I cleaned it out and replaced the plugs, but wonder if it might be time to change the plug wires. If so, on the ends that go into the (I think coil) do they just pop on or is there something else I might need to know to remove them without breaking something?

Thanks in advance for any advise. I really enjoy trying to learn about this wonderful beast and what makes her tick, but I don't wish to do more harm that good to her during my adventures through her innards.
 
Annual? That sounds excessive - by a factor of two or three. Is the 1200 much more prone to valve clearance changes than other bricks?

(And would the valves become tighter with age? I'd think the opposite.)

Given that they are in spec, why not just close it up and call it a day? The disassembly and reassembly presents all kinds of opportunities to screw something up. If it ain't broke....
 
The valve clearance does become tighter with miles. I hope you did not remove the spark plugs before you checked the clearance. I would not adjust the clearance until it is below spec.
 
The valve check on an annual basis is because I have 18,000 miles on the bike since last year.... The 6000 mile trip to Salem this summer for the rally added up quite nicely. I usually run about 15,000 miles a year, but with this bike, (and much more time to travel now that I am mostly retired) means that I'll be hitting the 16,000 mile maintenance interval for valve checks.

I did remove the spark plug to turn the engine (after cleaning and vacuuming the outside of the valve cover and spark plug area before disassemble. I know the manual says not to, but I don't see how you could turn the engine with the plug still in.... Any suggestions would be greatly appreciated.
 
The valve clearance does become tighter with miles. .

If you would say why, he will actually believe you: The valve head moves itself into the seat with time. The valve "settles" and the valve shaft moves toward the cam/rocker and the clerance becomes smaller.

I am not sure about the K-bikes, but the Oilheads have a valve check/adjustment interval of 6,000 miles. Could be twice a year, depending on your mileage
 
If you would say why, he will actually believe you: The valve head moves itself into the seat with time. The valve "settles" and the valve shaft moves toward the cam/rocker and the clerance becomes smaller.

I am not sure about the K-bikes, but the Oilheads have a valve check/adjustment interval of 6,000 miles. Could be twice a year, depending on your mileage

Mike, thanks, I was wondering why that was.

I've moved from a K75C to an R1100RT. At its untimely end, the K75 had 109,000 miles and ran like a top. Its valves were inspected by the original owner at about 30k, adjusted at 66k, and I was planning to check them myself this summer. That's why I find the expectation of <20k intervals for the K1200 surprising. I gather there was some sort of electronic service management in the K1200 that proved not to work well, for which BMW then substituted a shortened inspection interval. But I wonder if that interval isn't more of a CYA move than a necessity.

The oilhead engine and valves are a totally different beast, of course. Since the clearance is held only by a threaded screw with a locknut, there's a lot more opportunity for things to move around than the K engine, where clearance can only change via wear on the metal parts.
 
The valve check on an annual basis is because I have 18,000 miles on the bike since last year.... The 6000 mile trip to Salem this summer for the rally added up quite nicely. I usually run about 15,000 miles a year, but with this bike, (and much more time to travel now that I am mostly retired) means that I'll be hitting the 16,000 mile maintenance interval for valve checks.

I did remove the spark plug to turn the engine (after cleaning and vacuuming the outside of the valve cover and spark plug area before disassemble. I know the manual says not to, but I don't see how you could turn the engine with the plug still in.... Any suggestions would be greatly appreciated.
If you have a center stand put the bike in 5th or 6th gear & bump the tire forward. If you don't have a center stand you will have to roll the bike forward in 5th or 6th gear. Removing the spark plugs before a valve clearance check can change the exhaust valve clearance.
 
Why would that be???

Good question. I have never heard of that concern. I suppose the torque of the plug could change the cylinder head shape a micro-meter or two, but hard to believe it can affect valve clearance.
 
Removing the spark plugs before a valve clearance check can change the exhaust valve clearance.

The exhaust valves are located below the spark plugs so upon removal of the plugs there is a chance that carbon particles will be loosened and fall down into the valve seat area causing the clearances to change. I.e. measure a larger gap than there actually is.


Tight exhaust valves will eventually lead to burnt valves. The unknown is at what point is the valve to tight and held open a tiny bit which starts the burnt valve and seat process.
 
The exhaust valves are located below the spark plugs so upon removal of the plugs there is a chance that carbon particles will be loosened and fall down into the valve seat area causing the clearances to change. I.e. measure a larger gap than there actually is.

Tight exhaust valves will eventually lead to burnt valves. The unknown is at what point is the valve to tight and held open a tiny bit which starts the burnt valve and seat process.

Interesting point. Never heard it before, but then it only really applies to horizontal engines.
 
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