Constant small oil leak - time for transmission vent?

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Maybe the seals need to bed in and thats why it stops after some miles. My bike leaked for the first 200 miles. I even brought it up to the dealer and he told me to keep an eye on it and he'll order me a new seal. Then it stopped. I added the vent at 15miles on the clock so you're probaly correct. At that time I also did an ignition upgrade and pinned my clutch basket so the ring gear doesnt fall off and cause me an accident like it did on my dads bike. Except he was taking off from a light so he didnt fall. I also torqued every nut and bolt as I found many loose (remember only 15miles). Changed exhaust, rempapped and adjusted timing chain. So I did a lot at once. My bike has never had one issue. Too bad the factory didnt do everything first. Oh well, we've been telling them for years now. Hopefully the 2017 are dialed in. We sent them vents to consider too. We'll see what happens. Lets hope they don't just steal the idea without even a thank you.
 
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I had (what the dealership claimed) was seepage from the crankcase seam so they cracked that open and sealed it. Hmmmm.......still oil accumulating in the same area. Changed the starter, oil miraculously disappeared. As advised by Matt Capri, the starters have a bad internal O ring (some, anyway). Over the past few hundred miles or so after a hard ride, I have minor seepage at the front of the primary case. Very minor. No drips. As stated, I wipe it off. Getting a new cover anyway due to road rash so I guess that should take care of it.
 
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Bought my 961 with 260 miles on the "clock". Evidence of a leaking primary (output) at the time. Changed the fluids and added the ONE07 vent at about 350 miles. Still leaking at 1000 miles. Stood the bike straight up on a stand and drained about 8 ounces of oil out af the tranny when perfectly level. Maybe just too much oil. We'll see if it still leaks. Taking it to AF1 Racing in Austin for a remap. May let them fix leak then if needed. Drilling out the baffels from the OEM Norton exhaust just to see what happens. They're baffels on both ends of the exhaust. Will report results. Cheers.
 
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OK so...

I checked the chain. Good 35mm slack.
Rubber seal looks in good condition and well fitted as well.

Changed the oil in transmission (as was suspicious full synth was put in at last dealer engagement) to semi synth - this fixed my graunching/juddering clutch on take up by the way.

Still a small leak.

Will fit trans vent but beyond that don't know what else to try?
Perhaps sprocket is on too tight, could that do anything there?

Regards.
Hi GKRyder. Seeing those words 'graunching/juddering' got my attention. I have tried differing oils and still have those two words on clutch take up. Can you confirm what cured yours please as its driving me nuts.
 
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Hi GKRyder. Seeing those words 'graunching/juddering' got my attention. I have tried differing oils and still have those two words on clutch take up. Can you confirm what cured yours please as its driving me nuts.
Possibly the seal between engine and transmission is shot/damaged at assy/ put in wrong.

Engine pressure pushing oil into the transmission.
 
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What kind of oil are you using for transmission, Richard? Did you try different brands?
 
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Would it pay to switch to a full synthetic after 8800 miles? The bikes pretty well broken in.
 
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Motul
4T
7100
10w40 MA2
100% synthetic ester
4-stroke oil
For motorcycles engine and
Wet clutch transmission
Meets JASO MA2
 
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Is you trans leaking from behind the countershaft sprocket ? There is a seal and o-ring that may be replaceable from outside after you remove the countershaft sprocket.
 

GKRyder

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Hi
Hi GKRyder. Seeing those words 'graunching/juddering' got my attention. I have tried differing oils and still have those two words on clutch take up. Can you confirm what cured yours please as its driving me nuts.
Hi

First question I have is:
Did this start happening for you after a service or some event (time / very hot day in stop start traffic/ parts replaced etc)?

With mine:

It ended up being plates (friction and steel) being in wrong order when clutch basket was inspected. So taken apart...put back.

With yours:
It could also be the straightness of the shaft..or slightly warped plates...or quality of oil...or clutch engagement (quality of clutch fluid?)
 
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Fast Eddie

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Motul
4T
7100
10w40 MA2
100% synthetic ester
4-stroke oil
For motorcycles engine and
Wet clutch transmission
Meets JASO MA2
Thanks Richard. Still 10w40 then.

My reason for asking is that I can’t help but think (based on zero real evidence) that 10w40 is too thin for such an old school engine as this.
 
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I'm not sure what this is?

End of a shaft , oil galley?



Always a bit weapy.

Looked at Richard's manual for clutch so seams to sit below clutch basket.

Thanks for any assistance.

I have a 2015 961 SE (one of 50 imported to the U.S.) and have now done 2,600 miles. From the time I've owned it, I've noticed an oil "weep" in the place you describe. Has never increased and does not drip, so I just wash it off when I clean the bike. I fitted a transmission vent tube from Richard #7 after about 600 miles, but no change. I installed the small plastic collecting bottle from the air box overflow recently and it filled up within 200 miles. Checking engine oil level should be done when engine is hot after about 25 miles, so I may have been a little full - will check ASAP.
 
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