80K Valve Check

[Byron]

Well my bike hasn't hit three years old yet, but pretty close, and I just did the 80K valve check yesterday. All were within specification so no adjustments necessary this time around.

I put all my prior valve check information into a spreadsheet to get a better overall look at how they have done. One of the things I noticed is that overall they have been fairly stable. You may ask, "what is stable?" so I'll clarify. For all 16 valves the average variance has been 0.00056" in over 80K miles. I have only adjusted 2 valves in 80K miles, one exhaust that needed it as it was under spec and one intake that was on the low side and I already had that side apart. There were 6 valves with literally zero change, 5 with -0.001", 3 with -0.002" and 2 with +0.001". Since a picture is worth a 1,000 words I've attached a screen shot of the numbers.

I can't really explain why some of the numbers are what they are but I've got an idea or two. A couple are, new shim not fully seated because of fresh oil applied to shim before putting it in. Cam position off a few degrees difference between measurements. Wear besides at the valve seat. All I can say is these are the numbers I came up with, and I do the checks twice to help avoid errors.

 

[Mellow]

Nice.. Thanks Byron, that's a cool look at it.

 

[DAS]

Nice. I assume you have the current shim size listed elsewhere.

 

[Byron]

I've never taken it all apart to get the info on shim sizes. I do have the sizes for the shims I have changed though. It's not something I'm worried about because I do have a shim kit on hand. At one time I thought about pulling it all apart but decided not to go through the extra work.

 

[SierraTango]

Nice way to look at everything over time Byron. What does the Mileage, Adjusted, +4% SH column stand for? Kevin

 

[islandstar]

Looks great, but one question.
Do you think on Cylinder 2, Front Exhaust on 5/26/07 might have given you a result closer to .010 if you waited till the next valve check rather than making the shim swap at the time?

Since some previous checks indicated a gap going away and then returning closer towards .006 or .010 specs, do you think its possible Cyl 2 front exhaust valve might have done the same w/o making the shim swap and waiting till the next inspection?

Just asking

Thanks,
Andrew

 

[Byron]

Nice way to look at everything over time Byron. What does the Mileage, Adjusted, +4% SH column stand for? Kevin

Kevin,

I'd done my homework before I purchased the bike and knew I needed to correct the speedo. After getting the bike back from having the dealer do the 600 miles service I added a Heal Tech Speedohealer. It corrected the speedometer but threw off the OD by 4%. So when I want to know the true mileage I subtract mileage before install from the total then take that number and multiply by 1.04 (mileage + 4%) and then add back in the before install mileage. Now I have to go back through my notes because I can't remember if it was 600 or 650 miles when I installed it.

 

[Byron]

Looks great, but one question.
Do you think on Cylinder 2, Front Exhaust on 5/26/07 might have given you a result closer to .010 if you waited till the next valve check rather than making the shim swap at the time?

Since some previous checks indicated a gap going away and then returning closer towards .006 or .010 specs, do you think its possible Cyl 2 front exhaust valve might have done the same w/o making the shim swap and waiting till the next inspection?

Just asking

Thanks,
Andrew

I wouldn't risk it or recommend waiting. I ended up with 0.008" twice so there was no denying that valve was out of spec. I don't understand how the gap grew by 0.001" on some valves from one check to the next, or in the case of the #1 back intake which was measured at 0.007" on the first check and 0.006" on the three next checks then back to 0.007" on the most recent. But I do know that if the numbers are out of spec then I will adjust the shim to bring them back in.

 

[RCS]

I wouldn't risk it or recommend waiting. I ended up with 0.008" twice so there was no denying that valve was out of spec. I don't understand how the gap grew by 0.001" on some valves from one check to the next, or in the case of the #1 back intake which was measured at 0.007" on the first check and 0.006" on the three next checks then back to 0.007" on the most recent. But I do know that if the numbers are out of spec then I will adjust the shim to bring them back in.

Great spreadsheet. I printed it out to use for my valve work since I have never done valves before. Thank you.

I also watched the one hour valve adjustment video for the ST1100 which was very informative.

In thinking it through after reading all the valve threads here, the valve gap (for example in intake cylinders 1, 2, 3, and 4 at 80K miles) could have increased if the cam wasn't perfectly positioned above the bucket on the two previous measurements -- but not likely. (I'm assuming the cams have to be aligned PERFECTLY above the buckets to get a good measure with those tight tolerances). It may be - as pointed out by someone else - that the cam and or bucket got worn down between measurements.

Since the intake cams are above the exhaust cams could that mean that oil isn't getting to your cam/bucket area in the intake valves?