Engine Mechanical Topics Discussion for motor builds, cams, head work, stripped bolts and other engine related issues. The good and the bad. If it goes round and around or up and down, post it here.

Compression release question.

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Old Dec 24, 2020 | 05:10 PM
  #11  
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Originally Posted by djl
Don't disagree with installing compression releases; they extend battery and starter life. However, static CR is really not the criteria for deciding if CRs are "needed" or not; the criteria is CCP. In the OPs case, even with 10.5 static, CCP is about 9.3 193 psi if his listed specs are correct. At 9.3 193psi CCP, IMHO, CRs are not "needed" but they certainly won't hurt particularly since the heads are already prepped for them.
I need to correct the previous post; I recorded corrected compression, not CCP; brain fart when transposing data from compression calculator to the post; corrections hi-lited above. This is the second brain fart of the year; really slipping.
 
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Old Dec 24, 2020 | 06:57 PM
  #12  
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No matter what is good or bad, since you have the heads off it’s time to get the CR going. The bike will start so much better. Mine sure did.
 
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Old Dec 25, 2020 | 06:44 AM
  #13  
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what year is the bike you may have to add wiring kit and move termiinals in fuse box around my is a 2009 ultra plugs are under tank but wires on fuse box have to be moved around using a wiring kit from harley if u can even get it, lots of parts for the twin cam have vanished since the m8 came out
 
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Old Dec 25, 2020 | 09:25 AM
  #14  
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Originally Posted by 2009blackpearle
what year is the bike you may have to add wiring kit and move termiinals in fuse box around my is a 2009 ultra plugs are under tank but wires on fuse box have to be moved around using a wiring kit from harley if u can even get it, lots of parts for the twin cam have vanished since the m8 came out
I believe the OP is adding MANUAL C/Rs
 
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Old Dec 29, 2020 | 03:15 PM
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Originally Posted by eighteight
I believe the OP is adding MANUAL C/Rs
Yes
Bike is 2001
 
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Old Dec 29, 2020 | 03:16 PM
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Originally Posted by Hillsidecycle.com
Once we crest the 10.0 cr number, in those, we install them.
Btw, that 257 will be soft on the bottom, fwiw.
Scott
Very soft on bottom. But those cams light up at 3000rmp and just keep going lol
 
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Old Dec 29, 2020 | 03:19 PM
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When I was having all kinds of starter grind issues, my dealer installed 1 manual CR on the rear cylinder, it made such a difference and let the bike crank so much easier, . When I swapped my engine to a 2014 out of a FLHX it came with the auto CR and I had the dealer wire it to activate them and the bike starts so easy. I can tell the starter doesn't struggle at all. Way Mo betta.
 
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