I keep hoping that one of the major motorcycle online sites or magazines will hop on this story and get the word out about fluid transfer between the transmission/primary case. So far I have seen zero interest and nothing in print or online to indicate that many people are even aware of the problem. Given the fact that a transmission could lock up due to lack of lubrication seems to me to be a potential safety hazard with big liability on the manufacture if someone is injured or killed. I am no "Safety Sam" but even I can see that sliding down a busy interstate (on your ***) at 75 mph with a locked up rear wheel is going to have a nasty outcome. Safety recalls seem to take a lot of time before things start to happen unless there is a public outcry. We continue to patiently wait for a resolution and a fix.

 

Back when this first came to light for us the dealership said the fluid was just low and added to the transmission. Little did I know it had move ~28 oz from the transmission to the primary. The second time the transmission was getting low I had decided to add the AIM clutch system so I pulled the derby cover from the primary and as I loosened the screws holding it on, fluid started pouring out! I tighten them back as fast as I could but it was a mess. Went and got a drain pan and put it under to catch the fluid and again went about taking the cover off. I got about 18 oz in the drain pan before it stopped coming out of the cover area and left the fluid level on the bottom of the opening for the derby cover. I then drain the entire primary and removed the primary cover. There are a bunch of changes from a Twin Cam so you cannot compare the two of them. They lowered the bottom of the primary down around the crankshaft area so the compensator swims in oil all the time now. This puts the crankshaft center line about even with the bottom of the opening in the primary cover where the derby cover mounts. So I can say without a doubt the oil was way over the seal position on the bike.

Again lets say there was a vacuum, it should draw primary oil into the engine since the seal is under oil, it didn't and doesn't. It would also have to somehow get the oil in the transmssion up high enough to get to the pushrod area. Please explain how that is going to happen as the transmission oil level is lower than the pushrod area and continues to get lower and lower as fluid moves out of the transmission and into the primary. The transmission will continue to move ALL its oil into the primary if you let it, so that's 30 oz that somehow jumps up into the air, gets into the pushrod and moves to the primary. Sorry, but there is no way in hell that can or will happen. The main issue is in the transmission and that has to be solve first. I believe once that is solved anything else will become a none issue.

 

Hey Steve, Any luck finding that sealed bearing you were looking for to test with? I've been following this thread from the beginning, and will keep following it until the problem is (hopefully) identified. Thanks to you and the others very much for all your hard work on this problem.

 

I would guess that the oil is being picked up by first gear then squirted through the trapdoor beating to get to the pushrod. As long as first gear layshaft is touching the oil it has the ability to pick it up.. Pics I see show it being the largest diameter gear in the tranny so it can reach the deepest..

 

The other thing to keep in mind is, If this is only happening on a few bikes, it may be an installation error. If it's happening on all of the bikes, its a design error. My bike was in for the 1000 mile service. I asked if everything was ok, did they find anything. Service writer said all is good. Hopefully, I don't have issues. He also told me that Harley said it is physically impossible for fluid transfer. Things that make you go hmmmm.

 

Now were back to the transmission as the issue, which is what I've said all along. That said, first gear alone doesn't do it all. The oil coming off of the gear is tossed in all directions and since there is only a small opening through the bearing plate, something has to keep the oil from returning back into the transmission. Once it gets through the bearing plate something else has to get it into the even smaller opening around the pushrod area. If the oil returned out of the bearing plate back to the transmission sump then the oil level would never reach the pushrod area.

 

Thanks for the clarification Steve. Yeah, as far as the how the oil gets into the pushrod tube... no idea. That's been quite the discussion since day one. I haven't forgotten it, just thought if there was an active vacuum maybe, just maybe when oil is pushed up to the pushrod tube, it's sucking in what is in front of it rather than in the past where there was maybe oil in the area but pressures were neutral so it didn't matter - no sucking.

When you had all that oil in the primary did you test it long like that? Did you think to check engine oil level at that time either? I went and looked at the new primary and what you've stated about crank level being closer to the bottom of the derby cover, makes sense if the primary is already over filled. At normal levels its far below the crank. I wonder if oil was up past this RED mark (cause it sounds like you had a ton of oil) that the spinning rotor kept oil off the crank seal enough that no noticeable primary to engine transfer could take place. I dunno, spit balling.

So you can see below that you probably wouldn't get any primary oil into the engine until it was way, way overfilled.

 

Well I would say that it's pretty obvious that if you can keep oil from getting to the clutch pushrod, you won't have any transfer.. I still suspect that here is something else helping the oil move through the mainshaft to the primary..

 

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Can I pose this again from post 375?

 

Very interesting. Do you have a working theory on "how" the oil can transfer in one direction only?