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Oil leak where crankcase halves join

9K views 12 replies 7 participants last post by  atlzsage 
#1 ·
I’ve attached a photo of where my leak is coming from. It’s right in front of the countershaft and oil is leaking out from where the two halves of the crankcase meet. It's a pretty slow leak, I'd say maybe a tablespoon per hour of runtime, but it's enough to be annoying for such a new bike.


I’ve already tried replacing the countershaft seal, and sadly that did not solve my problem.
Does anybody have an economical solution to stop this leak that doesn’t involve JB weld?


I fear that the only way to fix it is to pull the motor, split the case and reseal it and that is way outside my comfort zone.

Additionally, is there any risk to the motor if I just leave this leak unattended to?


It’s been leaking since shortly after I got the bike with 500 miles on if from the dealer. I’ve had the bike for almost a year and am just now getting around to diagnosing it (I know, shame on me). The bike has never been dropped so I can’t imagine why the crank case would randomly start leaking with just a few thousand miles on the bike.
If there are no economical solutions I may just let it continue leaking, but obviously if that could damage the motor somehow I wouldn’t want to do that.

Any insight would be helpful,
Thanks!
 

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#5 ·
Most likely just a slight defect from assembly. Probably not enough liquid gasket material in that spot. In theory an easy fix, but very labor intensive to do it, since they'd have to take the engine out, open it, and reseal everything. Without warranty, that would be an expensive repair for something that won't really cause you any issues. Just means you need to keep a closer eye on the oil level.

Speaking of that...how's the oil level? I've seen this happen when there is too much oil in the engine which causes a bit more pressure and it gradually seeps out.
 
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#6 · (Edited)
This is a good suggestion that the OP should look at seriously. When there is excess oil in the engine, the engine's reciprocating movement of the pistons pressurizes the crankcase and creates leaks that would not otherwise be there.

A common new owner error on a bike like the R3 which as a "sight glass" for checking oil level is that the owner fails to notice that the manual tells you to check the level in the sight glass WHEN THE BIKE IS UPRIGHT AND LEVEL, not on the sidestand. Reading the level when the bike is on the sidestand gives you a grossly lower reading than is real. So, you add oil and now you have way too much in the engine, and the crankcase gets pressurized, the oil runs hotter and so less viscous, and the combination pushes the oil our in places it was never intended to go.

Two ways to read the sight glass properly:

1. Easy way: use a rear stand so that the stand holds the bike level, not at an angle, and simply read the oil level in the sight glass.

2. Harder way but less costly and can be done anywhere without any tools:
- Put the bike on the sidstand
- Get on the RIGHTHAND side of the bike where the sight glass is
- LIFT the bike towards you off of the sidestand, using the handlebar (which provides the required leverage), until it is approximately level
- Read the level in the sight glass
- Gently let the bike tip back onto its sidestand by sloooowly easing the handlebar back to the left.

Jim G
 
#7 ·
Are you sure it's not coming from the bolt above the marked area in your picture? Look above that to the bolt with the copper washer. That washer holds oil back. Clean the area all around the suspected leak well. Then use a spray on underarm deodorant the kind that goes on white. Start the engine and see where the leak is coming from. I doubt it's the area you think. It's most likely coming from above

Sent from my SM-G930V using Tapatalk
 
#11 ·
I’ve attached a photo of where my leak is coming from. It’s right in front of the countershaft and oil is leaking out from where the two halves of the crankcase meet. It's a pretty slow leak, I'd say maybe a tablespoon per hour of runtime, but it's enough to be annoying for such a new bike.


I’ve already tried replacing the countershaft seal, and sadly that did not solve my problem.
Does anybody have an economical solution to stop this leak that doesn’t involve JB weld?


I fear that the only way to fix it is to pull the motor, split the case and reseal it and that is way outside my comfort zone.

Additionally, is there any risk to the motor if I just leave this leak unattended to?


It’s been leaking since shortly after I got the bike with 500 miles on if from the dealer. I’ve had the bike for almost a year and am just now getting around to diagnosing it (I know, shame on me). The bike has never been dropped so I can’t imagine why the crank case would randomly start leaking with just a few thousand miles on the bike.
If there are no economical solutions I may just let it continue leaking, but obviously if that could damage the motor somehow I wouldn’t want to do that.

Any insight would be helpful,
Thanks!
Hey, Im having the same issue with my R3. Can you tell me how much the cost to repair was? Or what you did to fix the issue? thanks
 
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