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Discussion Starter #1
With all the postings with Jack D's valve adjustment, here is mine. I am not as brave as Jack to tackle this myself. I have an appointment with the dealer in two weeks to check and adjust the valves. I checked them last week and have a tight intake valve and maybe a couple of tight exhaust valves. Here is my question. Since all of my valves are at the minimum clearances, would it be worthwhile to have the dealer change all the buckets to allow for the maximum clearances? This way I should be in good shape for a long time. Any pros or cons about this reasoning? I am attaching a spreadsheet that shows my last two valve checks. At approximately $16 per bucket, this would come out to $250 to change all of them, something that I really do not want to spend my dollars on, BUT!!!
Thanks for your comments!!!!
 

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Wrencher Extraordinaire
2005 K1200LT
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The info you don't have is the size of each of the current buckets. You (the dealer) may be able to swap some of the buckets around to get everything in specification with out actually replacing all of them.
 

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jzeiler said:
The info you don't have is the size of each of the current buckets. You (the dealer) may be able to swap some of the buckets around to get everything in specification with out actually replacing all of them.
I agree. I am hoping that if I ask politely, that the dealer will write down all of the bucket sizes for future reference. Even if the asked the dealer to change all of the buckets, I doubt that he will have that many (of the same size) in stock.
 

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Some dealers have a range of buckets and will do a swap rather than charge you for each bucket. However, even if your dealer is willing to do that I think he is going to charge you extra just for the time involved to do all of them. No harm in asking.
 

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Just happen to have (3) spare buckets on hand from previous adjustments. Let me know what size you need and I'll drop them in the mail to you, if I have the size you need.

That applies to everyone on this forum, if you need them, I'll give them up.

Not sure what sizes they are, would have to get off my butt and go to the garage and see.
 

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I'm going to tell you that I wasted more time trying to keep from ordering or buying and the hour and half in the cage to fetch the buckets that I needed..

Instead I fiddled for hours and found that I only could make the adjust 'closer/better' and not acceptable. Remember you have 16 adjustments and 16x16 the possibilities for moving buckets. I did not use the 'inches' measurements that you used for the valves. I felt it was generally easier to add and subtract using the metric measurements and I felt there were more measurement increments. Eventually I decided Friday night that I would just buy new buckets. I called my closest dealer on Saturday morning and did the two hour drive.. (actually 1:15 minutes... 65 miles) but I had to spend 45 minutes there looking at stuff... :D

OK, back to the task at hand...

My observation is that there is only one measurement that is acceptable. While running on the high side is OK it is not good. The high of the adjustment will start to produce performance deficiencies because you will be starting valve movement late and finish early so the intake and exhaust cycles will be short.

If you look at the metric measurement you will see there is only 'ONE' bucket that will work. If you are there now than that is what works.. I think technically you want to be as close as you can to the low side of the measurement to get the best performance from the valve adjustment. That is why I decided to buy the buckets I need.

I don't understand the technical reason the valves start to change the 'adjustment'. I did quite a bit of the simple math needed for this adjustment and the thing I came away with is... it is more critical to know what your exact valve adjust is so that the next time I know what changed. If I had been more precise in my measurements the last time I could have determined if any were changing and what the expected duration of the next change.

Net of this is IMHO changing all buckets to the next higher is expensive and counter productive.

Tomorrow I will do the deed and get the LT on the road as I need to go back to work next week and the LT is my transportation.
 

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jackd said:
Net of this is IMHO changing all buckets to the next higher is expensive and counter productive.
I agree that changing all the buckets to the maximum size may be counter productive. But I want to change any of the buckets that seemed to be a tight .006 (intake) or a tight .010) (exhaust). I will see what the dealer comes up with on June 8. Also since my dealer is 50 miles away, I am driving the bike there (stripped of plastic) and will have them check and adjust everything. With my luck, I do not want to be making multiple trips up and down I-95 for buckets.
 

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I believe that you missed my point.. IMHO there is only one bucket that will make the cut in any valve. The tolerances effectively allow for 6 mm of adjustment The .15 - .20 mm and .25 - .30 mm allows you to be only two places either .15 mm and .20 mm when you have a choice to do anything.

If every thing is equal you can either add .05 MM of adjustment or take it away. If you are at any other measurement between .15 mm or .20 mm your in adjustment you can't do anything productive or better with a change. Below 15 mm you need to do something but above .20 mm you can leave but performance of the engine will suffer..

Most of my intakes are .16, .15, or .17 except for the two that needed adjustment. They will stay that way. Most of my exhausts were near .25 but one was .28 and one was .30 and I could not make enough changes to make the .28 measurement work... so I wound up with one out of adjustment no matter what I moved. Down from my original two but still one would be out of adjustment. I decided to just fix the original two. Mike were about $14 and change each.
 

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jackd said:
I'm going to tell you that I wasted more time trying to keep from ordering or buying and the hour and half in the cage to fetch the buckets that I needed..

Instead I fiddled for hours and found that I only could make the adjust 'closer/better' and not acceptable. Remember you have 16 adjustments and 16x16 the possibilities for moving buckets. I did not use the 'inches' measurements that you used for the valves. I felt it was generally easier to add and subtract using the metric measurements and I felt there were more measurement increments. Eventually I decided Friday night that I would just buy new buckets. I called my closest dealer on Saturday morning and did the two hour drive.. (actually 1:15 minutes... 65 miles) but I had to spend 45 minutes there looking at stuff... :D

OK, back to the task at hand...

My observation is that there is only one measurement that is acceptable. While running on the high side is OK it is not good. The high of the adjustment will start to produce performance deficiencies because you will be starting valve movement late and finish early so the intake and exhaust cycles will be short.

If you look at the metric measurement you will see there is only 'ONE' bucket that will work. If you are there now than that is what works.. I think technically you want to be as close as you can to the low side of the measurement to get the best performance from the valve adjustment. That is why I decided to buy the buckets I need.

I don't understand the technical reason the valves start to change the 'adjustment'. I did quite a bit of the simple math needed for this adjustment and the thing I came away with is... it is more critical to know what your exact valve adjust is so that the next time I know what changed. If I had been more precise in my measurements the last time I could have determined if any were changing and what the expected duration of the next change.

Net of this is IMHO changing all buckets to the next higher is expensive and counter productive.

Tomorrow I will do the deed and get the LT on the road as I need to go back to work next week and the LT is my transportation.
Having the valve clearance on the high end of the spec, or even 0.001" looser, will change the valve timing such a negligable amount no one will be able to tell the difference. Having them 0.001" tighter than spec. will cause the valve to start opening just slightly on the "clearance ramp", which is a much slower movement than the actual opening/closing ramps on the cams. That is BAD, as it starts the high pressure gas seeping through the exhaust valve at very high speed, which can start eroding small tracks in the valve face/seat. That progresses to burned tracks that mean a valve grinding, or valve replacement will be necessary.

I never hesitated to run the valve clearance between middle of spec to 0.001 looser. No "feelable" performance issue will result, but will help prevent valves from wearing to below spec before next check.

The valves wear tighter because of the valve face and seat wearing, letting the valve seat lower in the head. If you ever get one wearing looser, that is a sign of something bad happening, either lifter, cam or cam bearings wearing. Those are worse than the valve/seat wear, as it is much more expensive to repair later.
 

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David, Thanks for clarification. Makes sense when you hear what the adjustment does. I'm assuming that your explanation is more critical for exhaust than intake.

I'll be checking them sooner than later even though I have a significant amount of the exhaust valves at the good side of the measurement. Shouldn't be such a big deal next time. A little bit of experience goes a long way.
 

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jackd said:
David, Thanks for clarification. Makes sense when you hear what the adjustment does. I'm assuming that your explanation is more critical for exhaust than intake. ------------------.
Correct, since the exhaust valve starts to open when the pressure in the cylinder is very high, at the end of the combustion cycle, but the intakes open and close at low cylinder pressures.
 
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