M8 trans fluid leaking in primary

[hattitude]

Thanks......

Hopefully they will remedy the issue... 

[masterp]

I'd like to know why it is happening too but I don't see this as much of an issue.  I guess if you take the facts and stretch them like ol' Armstrong then you could come up with some potential issue this could create.

In my mind a few unknowns that need to be answered come to mind.  How low does the oil level need to be in the transmission to cause an issue?  How high does the level in the primary oil need to get to cause an issue?  What effect does diluting primary oil with non-primary oil have on anything?

My take is that these bikes are great with very few issues.  This one may even get fixed at some point.  The older parts and bikes mentioned above all had their issues as well. 

I wouldn't lose any sleep over it.  It's something to help fill the pages of a forum though and it's interesting to have so many interested in working to find a solution.  I'll wait on the edge of my seat.

[Xyzzy]

Dunno if this is helpful or not:

I have 46,000 miles on two '17 Street Glides and I have not had this issue. I check my transmission oil weekly on both bikes. I use M1 75W90 gear lube in the transmissions. I would definitely smell that oil when I do primary oil changes. Plus, my primary has not been overfull at any time. I change the primary oil every 10,000 miles.

What is different about my bikes?

Neither bike has been above 3,000 RPM except for a few brief top speed runs when I first bought them. Maybe 2-3 miles total? The fastest speed I ever run for prolonged periods of time is 75 MPH which is under 3,000 RPM. I shift at 3,000 RPM as well.

[Bike31]

SC on the HD Forum agrees...under 3500 it's minimized...over that it's accelerated to where reportedly all but ~4oz can in his experience remain in the trans when tested on a dyno.

High RPM's are the reported contributing factor.

[FSG]

..  where reportedly all but ~4oz can in his experience remain in the trans when tested on a dyno.

so the way I understand english this reads that if there's 24 oz in the trannie before the dyno workout, there will be all (24) but ~4 oz remaining in the trannie after the workout

so 24 - 4 = 20 remaining in the trannie

or did SC mean to say that ~4oz is all that will remain in the trannie after the dyno workout

[Sunny Jim]

I disagree with masterp. I am not in the habit of wasting my precious time trolling through forums for the hell of it. It's a real issue that evolved in the M8 and it needs to be resolved. The fault is clearly apparent and us M8 owners have put our trust and $ into this new product. It's us first round of owners that determine whether this product is worthy. I took the M8 over the twincam with the assurance of HD and their innovation. I want my bang for buck!

[1FSTRK]

I disagree with masterp. I am not in the habit of wasting my precious time trolling through forums for the hell of it. It's a real issue that evolved in the M8 and it needs to be resolved. The fault is clearly apparent and us M8 owners have put our trust and $ into this new product. It's us first round of owners that determine whether this product is worthy. I took the M8 over the twincam with the assurance of HD and their innovation. I want my bang for buck!

I agree, something like this either works as designed or does not. This is technically an oil leak, it just leaks into the primary and not on the ground. If it leaked on the ground very owner would be outraged.

"If you are disappointed by our product, lower your expectations"  is not a good company policy.

[Wicked]

The thing to remember is HD has used this vent system on all these bikes starting from the mid 1980's when they went to the wet clutch, so they just need to Identify what they changed on the M-8 that is driving oil from the trans into the primary at higher rpm.

It would be a step backward and I am not sure if there is room inside the M-8 clutch to do it but on the old dry clutch Harley's up through the early EVO's or when a primary belt drive is installed the clutch hub nut gets bored and a seal is installed in it. If this was done you would just need to vent the primary. It will be interesting to see if they figure it out or patch it by going backward.

In this case it would be going forward. The one and only shovel I worked on, I believe the pushrod had some form of sealing and the primary had it's own venting. Not a bad idea and in many ways the correct way to do things. Slinger also an option but might not be an option due to room. Clearly not worth a damn the way it is in the M8. Like you say, let's see what's coming up for the fix. It would need to be retrofit to the 17s if the 18s come standard with the update.
Ron

Just an fyi Ron - back in those days the pri was designed to be a vacuum (lol!) as it collected motor oil for pri chain lube , and those who isolated the pri would normally leave the little drip hose open for a vent.

[rbabos]

The thing to remember is HD has used this vent system on all these bikes starting from the mid 1980's when they went to the wet clutch, so they just need to Identify what they changed on the M-8 that is driving oil from the trans into the primary at higher rpm.

It would be a step backward and I am not sure if there is room inside the M-8 clutch to do it but on the old dry clutch Harley's up through the early EVO's or when a primary belt drive is installed the clutch hub nut gets bored and a seal is installed in it. If this was done you would just need to vent the primary. It will be interesting to see if they figure it out or patch it by going backward.

In this case it would be going forward. The one and only shovel I worked on, I believe the pushrod had some form of sealing and the primary had it's own venting. Not a bad idea and in many ways the correct way to do things. Slinger also an option but might not be an option due to room. Clearly not worth a damn the way it is in the M8. Like you say, let's see what's coming up for the fix. It would need to be retrofit to the 17s if the 18s come standard with the update.
Ron

Just an fyi Ron - back in those days the pri was designed to be a vacuum (lol!) as it collected motor oil for pri chain lube , and those who isolated the pri would normally leave the little drip hose open for a vent.

Yes, I remember now. Maybe I wanted to forget.   I did a vacuum test for the primary on that bike. The vacuum was supplied by the engine oil scavenge pump IIRC, so the PR seal would be a must for that vacuum to take place.  It failed the test for several reasons and was converted over to the primary having it's own oil , rather then engine oil. It still had a seal for the pushrod though. A very simple mod to incorporate into the M8, I'd think with a small vent T'd into the trans vent for primary? Partial sealing would also reduce transfer to bare minimum yet allow breathing from current location. We'll see what they come up with. One thing for sure is, it can't be left as is.

Ron

[Xyzzy]

Would a heavier gear oil (75W140) migrate less?

[rbabos]

Would a heavier gear oil (75W140) migrate less?

Not really.
Ron

[02roadcling]

Would a heavier gear oil (75W140) migrate less?

Not really.
Ron

I filled mine with regular grease. So far, so good.

   cling

[rbabos]

Would a heavier gear oil (75W140) migrate less?

Not really.
Ron

I filled mine with regular grease. So far, so good.

   cling

Yes, but must be synthetic. Preferably Liquid Moly grease.
Ron

[Bike31]

..  where reportedly all but ~4oz can in his experience remain in the trans when tested on a dyno.

so the way I understand english this reads that if there's 24 oz in the trannie before the dyno workout, there will be all (24) but ~4 oz remaining in the trannie after the workout

so 24 - 4 = 20 remaining in the trannie

or did SC mean to say that ~4oz is all that will remain in the trannie after the dyno workout

..."If left to itself and you operate at these RPM levels for longer periods of time it will transfer all but about 4 oz out of the transmission."...

Mi Anglish Socks!

[masterp]

...The fault is clearly apparent...

But is it really a fault?  That's my question.  There may be someone on here that has the inside scoop on what the design intent was and they just haven't weighed in yet.  Who knows, this oil transfer may also be a known average rate and it may be the reason the maintenance schedule was written as it was. 

If the two components were not already connected by an intentionally open pathway I may consider it a leak.  There is nothing I've read or seen yet that tells me this "fault" should not happen.  Just knowing they are connected by an open shaft I'd fully expect it to happen and would be more surprised if it didn't.

Aftermarket open and dry primary manufacturers are so confident that it is a normal occurrence that they design, build, and ship a sealed clutch basket nut to prevent the oil from leaving the transmission through the hollow shaft.  This has been the case since the beginning of the design.

[Bike31]

There were transmission part changes for 2017...housing metal and gaskets. I don't know for sure but maybe oil is being pooled or exposed where it can get transferred easier than in earlier designs?

[FSG]

Bike31      yes Engrish 

well my 2c is the gears on the mainshaft spinning in the forward direction are acting as impellers and thrusting oil toward the trapdoor bearing, through the bearing and against the clutch slave cylinder and from there through the mainshaft into the primary

now why didn't this occur in the 2016 models, they had a different clutch slave cylinder and o-ring, maybe the oil was thrust through the trapdoor bearing but due to the different slave it had somewhere to go other than into the mainshaft

I haven't seen one in the flesh for a while so like others I'll have to wait to see what the MoCo does

A sealed bearing in the trapdoor would fix the problem BUT who wants that    

If I had an M8 I'd be modifying the side cover adapter so that the oil could get back into the trannie

[Bike31]

The secondary clutch actuator assembly for 2016 (37200023) was changed for 2017 to two P/N's...first it was 37200131 then superseded by 37200131A.

Maybe they fixed the oil transfer problem via 2017 actuator parts changeout and kept it a secret by bike S/N.  Speculation.

There's an O-Ring listed for 2016 (11900035) that looks like it seals the rim of the actuator to the inner side cover shown above. Maybe it's integral to the 2017 actuators but not spec'd separately?

Is there another seal around the actuator part that moves the clutch rod?

Source: http://www.docshd.com/OEMpartfinder.htm

[Rockout Rocker Products]

I got my '15 Limited Low back today. It has (more or less) the same clutch as the M8. 7500+ miles since the fluid was changed, lots of spirited riding including some dyno time.

Trans fluid level is dead on full.

[Sunny Jim]

Personally, I am seriously precious about My M8. I want it to be right. If it can't be at least as good as a twin cam then I don't want it , nor would I recommend it. It's issues like this that create doubt for me.
I think there is no arguement here. I appreciate you guys digging in to identify the problem. If it were any other vehicle eg Toyota, Yamaha BMW etc, they would be on to it. That's my experience of over 40 years.
Speaking of precious ' the wife backed over it with the 4wd on Wednesday '
Not happy !!!!!

[04 SE Deuce]

If run hard enough, long enough, the trans/shifting will let you know there's a problem.

masterp,  your wasting energy arguing.

[Durwood]

..  where reportedly all but ~4oz can in his experience remain in the trans when tested on a dyno.

so the way I understand english this reads that if there's 24 oz in the trannie before the dyno workout, there will be all (24) but ~4 oz remaining in the trannie after the workout

so 24 - 4 = 20 remaining in the trannie

or did SC mean to say that ~4oz is all that will remain in the trannie after the dyno workout

..."If left to itself and you operate at these RPM levels for longer periods of time it will transfer all but about 4 oz out of the transmission."...

Mi Anglish Socks!

This is what we are testing now, mine had 16oz in it after 1000 miles on the drum and 250 max power runs, that's a pint and if it stops there I will accept it and move on.

[Sunny Jim]

HD forum gas 5 pages of discussion on this very subject.

[Rockout Rocker Products]

Once serviced few check trans and primary lubes. Why bother unless there's a visible leak? When time for change most drop the used and refill with new.

Who measures drained oil unless you have a special need to do it? Like now for M8 owners.

Any clutch incompatible lube in the trans will be a problem for some if it migrates to the primary.

This rings true to me. I have the same A&S clutch in my '15 Limited Low. Have I had any problems? How would I know.... as said it never leaks so I never check it. My bike is out getting dyno tuned along with other things, I'll take a look when I get it back. 

I had the same thought as you when Bike31 posted his reply. I am adding a trans fluid check to both pre and post dyno check lists.

Y'know, now that I think about it.... if this had ever been an issue with twin cams I think it would have surfaced by now. LOTS of people running the Pepto Bismol in their trans, with regular lube in the primary. If there was any migration seems it would be apparent at drain time.

 

[96349]

Clutch Pushrod would be the only way it could get in the Primary from the Tranny

Ding, ding, ding. I think we have a winner here! I don't know how this could be fixed without a new pushrod being installed. This is going to be interesting as to the fix.