Oil leak diagnosis
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Joined: Dec 2014
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From: North Carolina
Oil leak diagnosis
Hey guys. Sorry for the novice question here. I am trying to find out what is causing a few of the oil leaks on my bike. its a 2nd hand 2007 night train with just over 10k. I have two leaks that have appeared. one on the top end of the rear cylinder (1st pic) and the other one is behind the rear cylinder where the engine meets the tranny (2nd pic). The top end leak is new but the one behind the cylinder has been noticeable since the first time I rode it, but has gotten more severe since changed the oil to synthetic. I am curious as to what caused these leaks and if it is normal for a bike with 10k on it to start having these kinds of issues. I am trying to find out if this is a major concern or something to deal with. Thanks for any advice you guys have.
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Joined: Dec 2014
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From: North Carolina
Btw I know the oil leak behind the rear cylinder is gonna take a lot more maintenance than the top end leak. I am gonna attempt to fill the pry point with gasket maker and see if that is the source.
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From: Fort Worth, TX
Rear cylinder rocker box leak, very common. I know you said the leak in the top of the transmission was older but a lot of times that oil is the oil coming from the rocker box, it runs to the back of the cylinder and drips down. To find the leak I would clean all the oil off really well, then start the bike and let it get hot. Turn it off and come back later and see if you can find the source. If no oil is present, start the bike again for a bit or take it for a short slow ride around the block. the point is to find the source without letting the oil blow all over making finding the source hard.
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Rear cylinder rocker box leak, very common. I know you said the leak in the top of the transmission was older but a lot of times that oil is the oil coming from the rocker box, it runs to the back of the cylinder and drips down. To find the leak I would clean all the oil off really well, then start the bike and let it get hot. Turn it off and come back later and see if you can find the source. If no oil is present, start the bike again for a bit or take it for a short slow ride around the block. the point is to find the source without letting the oil blow all over making finding the source hard.
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This is more of a nuisance than a problem. Usually just pulling it apart and putting a new gasket, torquing it down properly will cure it.
Depending on the place sometimes you can just re-torque the part.
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From: North Carolina
Oil leaks are a sign that the two mating surfaces are not perfectly flat, and that the gasket is not sealing completely, or that the gasket was not properly installed, torqued down.
This is more of a nuisance than a problem. Usually just pulling it apart and putting a new gasket, torquing it down properly will cure it.
Depending on the place sometimes you can just re-torque the part.
This is more of a nuisance than a problem. Usually just pulling it apart and putting a new gasket, torquing it down properly will cure it.
Depending on the place sometimes you can just re-torque the part.
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Joined: Dec 2014
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From: North Carolina
I had time to check the one on the corner where the leak is coming from. My plan for next week once I have time is to get the tank off and do a proper torque sequence on all of the cover bolts.
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From: Doghouse... mostly
Try just unbolting the back tank bolt and then loosen the front a little then use a block of wood like a 2x4 to hold the tank up and out of the way first. If the mating surfaces weren't perfectly flat with each other you can torque the bolts all day long and not get anywhere. Good luck.
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Try just unbolting the back tank bolt and then loosen the front a little then use a block of wood like a 2x4 to hold the tank up and out of the way first. If the mating surfaces weren't perfectly flat with each other you can torque the bolts all day long and not get anywhere. Good luck.
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