[elime]

I did a compression check on my TW's. The one I ride a lot is 143 and the parts bike is 148.



A quick search came up with some different results others have gotten:

Silverhead got 160.

Goofy Footer 135

macbig2K1 says 128 is good.



Does anyone know for sure what it is supposed to be?

 

[jbfla]

Hi Tony,



I don't think there is one specific number.



From experience and research , 100 psi is the minimum for proper combustion.



Generally, anything between 125 to 150 is considered good, although I've seen some higher.



Jb

 

[silverhead]

The service manual mentioned that anything north of 150 was 'a problem.' Mine was 160 (as read on two different testers.)



I should check mine again now that I've ridden the bike about 250 miles since I purchased it. It might have had a ton of carbon in the combustion chamber. My bike's running fine and I'm not hearing it ping on 87 octane, non ethanol gasoline, so I'm happy.



Most stuff will run even with compression under 100 PSI. To me it sounds like both of your bikes are A-OK.

 

[Leisure Time Larry]

Read this.

 

[elime]

Read this.

That is what I was looking for. I even posted in it twice!



OK then, 128 good, range is 114 to 149. I am golden!!! Thanks.