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So I did a compression test on my 2000 and found both cylinders are running at 146 psi.
I am at about 1000 feet above sea level.
I double checked the valves were to spec.
I did the oil drop test and then it went to about 165 - 170 on both.
The manual say 142 min 170 max at sea level.
So I am wondering with me at 1000 feet the compression would be lower then at sea level, but to what extent?
Am I to assume I need to look at the rings this winter?
After all this is 21 year old bike with no known engine work done.
 

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Administrator - "Loose Nut" - Houston, Texas
2001 Vstar 1100 Classic (sold), 2006 HD Electra Glide Ultra Classic
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I wouldn't do anything till it it was in the 120s. But that's me.

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2005 V-Star 1100 Classic
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So I am wondering with me at 1000 feet the compression would be lower then at sea level, but to what extent?
I think the answer to that is, 1" HG per 1,000 feet, or about 0.5 psi. (edited - I was way off)

You've definitely got good compression. Sleep well.

Also good to know, the fact that they are so close together is excellent news. Unusual wear never happens so consistently.
 

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2005 V-Star 1100 Classic
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I realized my off the cuff answer was way off. Looked it up and edited above.

Which isn't a useful answer either. Let's think this through.

Average atmospheric pressure at sea level is 14.7 psi. At 1,000' it is 14.2 psi.

14.7 / 14.2 is 0.965. Which means that at 1,000' there is 0.965 as much air per given volume.

So your 140 psi compressed air at 1,000' / 0.965 = 145 psi at sea level. Basically insignificant until you get much higher than 1,000 ASL.
 
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