M8 Help, low compression psi
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From: Mn
M8 Help, low compression psi
Dry CCP test, TB blade held open, ACRs unplugged. 120psi both cylinders.
Everything the same except add 5ml of oil, psi jumps to 190 on both cylinders.
Bike only has 100 miles on it, typically if you jump psi in a wet test its not a 70psi jump....Only mod aside from intake/exh is S&S cam .anybody have any ideas???? Thanks in advance
Everything the same except add 5ml of oil, psi jumps to 190 on both cylinders.
Bike only has 100 miles on it, typically if you jump psi in a wet test its not a 70psi jump....Only mod aside from intake/exh is S&S cam .anybody have any ideas???? Thanks in advance
Dry CCP test, TB blade held open, ACRs unplugged. 120psi both cylinders.
Everything the same except add 5ml of oil, psi jumps to 190 on both cylinders.
Bike only has 100 miles on it, typically if you jump psi in a wet test its not a 70psi jump....Only mod aside from intake/exh is S&S cam .anybody have any ideas???? Thanks in advance
Everything the same except add 5ml of oil, psi jumps to 190 on both cylinders.
Bike only has 100 miles on it, typically if you jump psi in a wet test its not a 70psi jump....Only mod aside from intake/exh is S&S cam .anybody have any ideas???? Thanks in advance
On the other hand, with only 100 miles on it the rings may not have seated yet.
Why are you checking the cold cranking compression anyway? Is it not running Ok?
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From: Mn
Are you holding the throttle body open while youre cranking it over. This has to be done manually with a screwdriver or something to push the plate open.
On the other hand, with only 100 miles on it the rings may not have seated yet.
Why are you checking the cold cranking compression anyway? Is it not running Ok?
Bike is having a starting issues, but that is related to my Tmax module...But in my working thru diagnosing the no start I decided to do a compression test and about fell over.
Then decided to drain the cam chest via the allen head underneath and got a little more than 8ozs of oil out of there....Not a happy camper already with this M8
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Joined: Nov 2015
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From: Mesa AZ
I know you must be bummed, but if you do have a problem with the rings its a good excuse for the 120" kit from Fuel Moto. You've already got the cam and it sounds like your warranty is gone too. Don't give up on the M8, it's a great engine when it's working. You might want to wait and install the S&S cam plate and oil pump if you are having issues with excess oil in the cam chest. I'm no expert so I can't tell if 8oz is a huge amount of oil in the cam chest?
Maybe run it for a few hundred miles and check everything again?? Good Luck
Maybe run it for a few hundred miles and check everything again?? Good Luck
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From: Mn
I know you must be bummed, but if you do have a problem with the rings its a good excuse for the 120" kit from Fuel Moto. You've already got the cam and it sounds like your warranty is gone too. Don't give up on the M8, it's a great engine when it's working. You might want to wait and install the S&S cam plate and oil pump if you are having issues with excess oil in the cam chest. I'm no expert so I can't tell if 8oz is a huge amount of oil in the cam chest?
Maybe run it for a few hundred miles and check everything again?? Good Luck
Maybe run it for a few hundred miles and check everything again?? Good Luck
Im pretty concerned though as until the ccp is figured out all that lost compression psi is just going into the case, which is not cool. These things dont need any help sumping.
As far as the 8ozs, HD originally said 3ozs in the chest then bumped it up to 6ozs. And what I find odd is I believe they want you pulling the CPS to check how much oil is in the chest. Why pull a sensor that is not at the lowest point, when there is a drain plug right there????? Me thinks HD has some splainin to do
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From: Okmulgee
Right, thats what the guys at FM said theyd be happy to sell me the 120kit....Not that Im opposed, but screw that HD cant void a warranty claim against bad jugs/rings over a cam swap. Theyve got nothing to do with eachother.
Im pretty concerned though as until the ccp is figured out all that lost compression psi is just going into the case, which is not cool. These things dont need any help sumping.
As far as the 8ozs, HD originally said 3ozs in the chest then bumped it up to 6ozs. And what I find odd is I believe they want you pulling the CPS to check how much oil is in the chest. Why pull a sensor that is not at the lowest point, when there is a drain plug right there????? Me thinks HD has some splainin to do
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