Valve Adjustment Feel???

[groeger]

I adjusted the valves on my newly acquired 2001 R1150GS this past weekend. Felt like I did on OK job. However, I would liek to perfect this in the near future. How would you describe the feel of the feeler guages when adjusting your valves?

[kbasa]

Slight drag on the feelers.

I loosen the locknut and back the adjuster off a bit with the allen wrench. I place the allen wrench so it can fall down until it meets resistance. That spot, where the allen wrench stops turning, is where you want your tightness adjusted to.

You should feel a slight drag on the feeler as you move it in and out. If you think it might be too loose, try and shove the next size up feeler gauge in there. If it'll go, it's too loose.

[PMonk]

I like to check clearances before loosening anything up with proper size and next up size. At my 42m service I loosed the left side and adjusted but they really were close. On the right side I didn't have to do any adjusting at all.

Follow up with carb-actually throttlebody sync and you are good to go.

[riderR1150GSAdv]

The biggest trick,IMHO, is to make sure that all 4 feeler gauges have the same resistance feel to them (if one uses the 4 gauge method), when sliding them back and forth. This ensures all valves are adjusted the same and makes the engine run smoother. Just my 0.02 cts YMMV etc, etc :wow

[MCMXCIVRS]

The biggest trick,IMHO, is to make sure that all 4 feeler gauges have the same resistance feel to them (if one uses the 4 gauge method), when sliding them back and forth. This ensures all valves are adjusted the same and makes the engine run smoother. Just my 0.02 cts YMMV etc, etc :wow

Exactly, the feel will be different for everyone, but most importantly they need to be equal. A bit tighter or looser will not have a major effect, but variations may. When it is adjusted properly, it should have a little drag but not excessive. If if falls out on its own, its too loose. Once the feeler gauge is pulled out, it should be able to be reinserted without forcing. If it won't slip back in, its too tight.

[dlearl476]

If you think it might be too loose, try and shove the next size up feeler gauge in there. If it'll go, it's too loose.

All you need to know to start. "Feel" can be developed from there. Then there is devoloping the technique of keeping the adjustment as you tighten the locknut.
:doh

The biggest trick,IMHO, is to make sure that all 4 feeler gauges have the same resistance feel to them (if one uses the 4 gauge method), when sliding them back and forth. This ensures all valves are adjusted the same and makes the engine run smoother. Just my 0.02 cts YMMV etc, etc :wow

Exactly, the feel will be different for everyone, but most importantly they need to be equal. A bit tighter or looser will not have a major effect, but variations may.

No offence guys, but the tolerance on valve clearance is ±.01 mm. If a .10 goes and an .11 mm doesn't, it doesn't need to be any more precise than that. If you can "feel" a difference in performance with valves adjusted any more precise than that, I would be, well, surprised.

[riderR1150GSAdv]

That is right if you use the go-no-go method. If the 4 feelers are used it is a matter of 'feel' and that comes also with experience. In any case most of us who do the valves at home do a better job than most dealers. YMMV

[MCMXCIVRS]

The valve clearance affects the valve timing, thus, having all valves set equally will help achieve much smoother engine operation. So, yes it is important.

[kbasa]

The valve clearance affects the valve timing, thus, having all valves set equally will help achieve much smoother engine operation. So, yes it is important.

I've always found that a careful, precise valve adjustment is the best way to make sure your single plugged oil head doesn't surge.

[BradfordBenn]

I've always found that a careful, precise valve adjustment is the best way to make sure your single plugged oil head doesn't surge.

+1

[j-budimlya]

I've always found that a careful, precise valve adjustment is the best way to make sure your single plugged oil head doesn't surge.

That and a careful, on-bike TB balance....and new plugs....

I can feel it "purring" now...... :thumb

[roundelrider]

The valve clearance affects the valve timing, thus, having all valves set equally will help achieve much smoother engine operation. So, yes it is important.

Actually, it affects valve lift not the timing. :)

[PGlaves]

Actually, it affects lift, possibly overlap, and duration. Timing defined as start of opening is altered. Timing defined as center of lift is not.

[DADODIRT]

I use the next higher size and next lower size to check myself. Also use two gauges for each intake/exhaust. Using two will allow you to make sure they feel the same.

[MCMXCIVRS]

Actually, it affects lift, possibly overlap, and duration. Timing defined as start of opening is altered. Timing defined as center of lift is not.

Correct.

If the gap is wider, the cam will rotate further before it closes the gap and begins to open the valve (retarding the valve timing), and it will return the valve to fully closed sooner. Vice versa, a tighter gap will cause the valve to begin opening sooner (advancing the timing) and stay open longer. Thus the duration and overlap are also affected as these are components of the timing. The total valve opening (lift) will also change, but that is a much less significant affect.

Even if all the valves are equal, but not at the correct clearance, the engine will have different power characteristics due to the valve timing change. The significance of this is not as great at idle since the slower engine speed allows lots of time for the air/fuel to enter and the exhaust to escape. As engine rpms increase, the time avialable for the air/fuel to enter and exhaust to exit decreases, so the valve timing becomes much more important. If the gap is wider, the engine may not get optimal air/fuel delivery and/or may not adequately purge the exhaust gases from the cylinder. A narrower gap can also have detrimental results to performace. Ultimately though, unless the gap is significantly varied from the specs the effect will be minimal.

The real problem shows up when there is an imbalance between the cylinders. Then you essentially have cylinders that are tuned differently and will be nearly impossible to balance throughout the rpm range. This will affect power, throttle response, economy and will produce more engine vibrations.

[dlearl476]

WOAH, STOP THE PRESSES.

Somebody better get on the horn and tell every engine manufacturer in the world that their valve clearance tolerances are woefully inadequate.

Perhaps some engine builder/mathematician can come along and tell us to what decimal place of a second or percentage point the valve parameters change with a difference of clearance in .00X mm range, but I'd take a WAG that it would be easier to discern whether your bike was running motorcycle specific oil vs auto oil than to "feel" if one of your valves was .003 mm different than the rest. Maybe on a 900hp F1 running at 19K rpm, but on a BMW @ 5, NFW. Ambient temp and humidity are infinitely more important, along with any number of settings/adjustments on the engine.

Then again, I've been known to wear brown shoes with a blue suit. :D