Pinion Spline Questions???

[Peteg]

I've been reading treads on spline maintenance and I have to admit I'm more than a bit confused. Moly 60 paste, High moly grease, Water proof marine grease??? I've got this green water proof marine grease the guy who built my sailboat trailer sold me. I was pulling the boat from Texas to Key Largo Fl. Drop the trailer into the sea water ramp, stay on the boat for 2 weeks drop the trailer into the sea water again and trailer 1500 miles home. He said no problem and he was right. Who knew!

My bikes got 46,000 miles on it, and  all the splines look good to me. When I first pulled the drive shaft I was pretty concerned about apparent ware on the input end of the drive shaft and pinion cup spline, except that after staring at them a bit and looking at Chris' power point pictures I'm thinking what I saw as excessive ware is really machined bevel to allow for swing arm movement?



So my pinion cup spline was either filled with heavy water proof grease or moly 60 paste I'm thinking the former, same with the universal end spline on the drive shaft.

I found no oring, but there are a lot of threads indicating that the oring has no function as the drive shaft is enclosed.

Lastly I found some gear oil mixed in with all the grease in the cup spline, indicating to me that the passive gear oil lubrication ports still work.
 
Although the heavy grease seemed to work, I'm thinking about going back to light grease as I believe the gear oil lube system is working on the pinion cup wet spline, so why clog it up? I have moly 60 paste that I was planning on using on the dry wheel spline and dry universal spline.

I think I'm ready to complete the service without the oring?

I run a MC tire on the back so I should be in here often enough.

[98valk]

"Lastly I found some gear oil mixed in with all the grease in the cup spline, indicating to me that the passive gear oil lubrication ports still work."

grease is oil suspended with thickeners.  during usage the oil can come out of suspension when doing its job. this would be the oil u are seeing unless during disassembly the final drive was tilted forward for too long and allowing the gear oil to migrate through bearings and seals.
  No engineer in their right mind would design a piece of equipment to have gear oil and grease mix together.  both are incompatible with each other and there would then be Zero lubrication.

[Peteg]

So I found another thread indicating that for what I'm doing I won't even see the pinion cup oring. So I should be good with my 3 oring set and new thrust washer only to complete the final drive service, correct?

[98valk]

the seal on the end of the driveshaft, I change every other tire change. also check the condition of the stopper ring on the end.

https://www.partzilla.com/product/honda/40221-MB0-000?ref=6cd8afeb3528807bbe9c09db6512fe3cc647977a

[Chrisj CMA]

Go with a light coat of grease not paste. A grease with moly would be preferable but a grease without moly would be better than moly paste. If you by chance have some of the Honda moly 60 “paste” in the black round tube it’s perfect as it’s really a grease not a paste. Honda intentionally mis marked/markeded it.

[sandy]

 My OEM service manual says to use a 2% moly grease. I have Valvoline Durablend grease which states a 3% moly content. i use it on both ends of the drive shaft.

And yes; the drive unit gear oil does migrate into the pinion cup.

[Peteg]

Cool, thanks Chris. What I have in hand is a light coat of STP grease, Moly-EP, for the pinion spline and expensive Moly Lube TS-60 Spline Lube from BeemerShop.com for the wheel and u-joint spline. I guess with all I've read now, there are many cheaper options to the Beemer Shop, but it's what I have in my shop now. I just cleaned up the splines, installed 3 red eyes. I'm ready to fill 150 cc's of lucas 75-90 synthetic hypoid gear oil and should have 2 new thrust washers on Tuesday. I'm really happy with what I see. I'm sure I could just pour the old gear oil back in and get $20 back from Autozone lol.

[Peteg]

Yeah Sandy, I knew I read that on an old thread. Sometimes it's hard for me to tell what's correct and what's opinion. Anyway I'm amazed my passive lube still appears to be working, even if it is just my imagination. I get that it's a Honda and you expect all the pumped jetted lubrication in the engine and transmission to still work after 26 years, but for the gear oil the ring gear is throwing to drain it's way down into the pinion spline? and then for the excess to drain it's way back into the case and have those little gravity bores?  stay clear for that many years. Not sure I believe it myself. Must just be something some old VRCC member made up to confuse me.

[Chrisj CMA]

Just for the info/comparison I just did a rear end service on a VTX1800. It’s fairly low miles and looked as if no one had ever put a wrench to the final drive nuts. 

When I pulled the drive shaft out of the pinion cup it was shiny clean with a heavy coating of what looked and felt like final drive lube. It was so clean and nice looking I just stuck it back in.

I don’t have a VTX book so I didn’t want to change what looked like a good thing going on.

[98valk]

And yes; the drive unit gear oil does migrate into the pinion cup.

impossible. there is zero path for gear oil to migrate during normal operation and installation.  an engineer would not design it to mix gear oil and grease.

cut away view in tech manual shows oil shaft seals, to keep oil in the final drive gears.

[Avanti]

Take a properly filled Final Drive and allow the pinion to tip forward on a bench for about ten seconds and there will be a need to clean up gear lubricant off the bench.

[98valk]

Take a properly filled Final Drive and allow the pinion to tip forward on a bench for about ten seconds and there will be a need to clean up gear lubricant off the bench.

I stated "during normal operation and installation".

[Chrisj CMA]

Take a properly filled Final Drive and allow the pinion to tip forward on a bench for about ten seconds and there will be a need to clean up gear lubricant off the bench.

I stated "during normal operation and installation".

You said “zero path”. There is a path if you can do as Avanti says. (I have not tried that) but that would mean, maybe a small amount of lube can find that path during normal operation.

[Peteg]

I love reading all this stuff, even if I am easily confused. This guy did a really cool video on this subject. He even put's a little shot of gear oil in the pinion spline prior to assembly. This is just a guess, but best I can figure out the light coat of grease aids assembly while the pinion spline is actually a gear oil lubricated spline. As long as it all works just follow Chris' power point and we're good, but it's fun to try and understand.

https://www.youtube.com/watch?v=INHdVZ2XJNQ

 

[Timbo1]

I cant say for certain Peteg but I'd think when I had that bike and did the final drive maint. I would have taken the driveshaft out to at least clean, inspect and grease.  Cant say for sure though, that's been about 3 yrs ago now and memory fails me.  If I had it would have had a light coat of moly with some water proof green grease applied on top. 

[98valk]

Take a properly filled Final Drive and allow the pinion to tip forward on a bench for about ten seconds and there will be a need to clean up gear lubricant off the bench.

I stated "during normal operation and installation".

You said “zero path”. There is a path if you can do as Avanti says. (I have not tried that) but that would mean, maybe a small amount of lube can find that path during normal operation.

"zero path for gear oil to migrate during normal operation and installation."

[Peteg]

Timbo, at this point who knows. You did a great job with the bike I love it. I wish you would have done the left rear double row bearing mod for me when you did the bike. My Colorado vacation might not have stopped short had the bearing mod been done LOL.

[F6Dave]

Just for the info/comparison I just did a rear end service on a VTX1800. It’s fairly low miles and looked as if no one had ever put a wrench to the final drive nuts. 

When I pulled the drive shaft out of the pinion cup it was shiny clean with a heavy coating of what looked and felt like final drive lube. It was so clean and nice looking I just stuck it back in.

I don’t have a VTX book so I didn’t want to change what looked like a good thing going on.

That's good to know. I had a similar experience on my '98 Tourer. After 50,000 miles I pulled the driveshaft pinion for the first time, and it looked great. I greased it anyway because I'd read all the warnings.

I wonder if some of us over-maintain these components. I've owned 7 shaft driven motorcycles, and rode 6 of them over 60,000 miles. Except for my 2 Valkyries, I never did any 'rear end' maintenance other than changing the drive oil. And I never had any driveshaft problems.

Even if Honda didn't design the best rear ends for these bikes, they can't be so bad that such extensive maintenance is needed at every tire change. And tearing it all apart over and over can cause new problems.

[F6Dave]

I posted a more detailed chronology of my driveshaft history on the 3 O-ring thread.

[Peteg]

F6Dave, I know right! When I road in the 70's my first bike was a 1974 Yamaha SX650. I loved the bike but I wanted to ride cross country so I bought a 1976 Yamaha 750 triple drive shaft bike. Touring, it was great to be rid of all that chain maintenance and mess. Now I have a 2016 Triumph Street, kind of Triumph's modern classic version of the 74 650. To me with all the engine balancing, fuel injection, computer controlled throttle based on MAP, it's hardly still a motorcycle. It's fun to ride, but I tend to go too fast for an old grandpa. The new chains are so clean and need so little lubrication, I just check the chain from time to time. It's always good. I bet if I put a high horsepower chain on it, it would go 30,000 miles without an adjustment. I guess we don't own these beasts because we're afraid to turn a wrench, lol.

Valk 98, this is only a guess, as I've never see the design drawings, and I'm just going by what a read in various threads, not any real knowledge: Your no path while running theory might just fall apart when you consider how the ring throws the gear oil when the bike is running down the road. Surely the drivetrain engineer did not ignore gear oil flow when he designed the gearbox. I suspect if he were reading this thread, he'd be laughing at all of us trying to figure this out. Just a thought with very little information. Don't know, you could be right.

[98valk]

F6Dave, I know right! When I road in the 70's my first bike was a 1974 Yamaha SX650. I loved the bike but I wanted to ride cross country so I bought a 1976 Yamaha 750 triple drive shaft bike. Touring, it was great to be rid of all that chain maintenance and mess. Now I have a 2016 Triumph Street, kind of Triumph's modern classic version of the 74 650. To me with all the engine balancing, fuel injection, computer controlled throttle based on MAP, it's hardly still a motorcycle. It's fun to ride, but I tend to go too fast for an old grandpa. The new chains are so clean and need so little lubrication, I just check the chain from time to time. It's always good. I bet if I put a high horsepower chain on it, it would go 30,000 miles without an adjustment. I guess we don't own these beasts because we're afraid to turn a wrench, lol.

Valk 98, this is only a guess, as I've never see the design drawings, and I'm just going by what a read in various threads, not any real knowledge: Your no path while running theory might just fall apart when you consider how the ring throws the gear oil when the bike is running down the road. Surely the drivetrain engineer did not ignore gear oil flow when he designed the gearbox. I suspect if he were reading this thread, he'd be laughing at all of us trying to figure this out. Just a thought with very little information. Don't know, you could be right.

I know I get it.
 I just posted on the three o-ring thread to F6Dave.

[Hook#3287]

It's obvious the final drive and rear pinion cup are interrelated for some reason, otherwise why would Mother Honda go through the expense of drilling the two holes in the cup.

There is also one in the swingarm I discovered years ago.  Could be more, but only one is visible.

Why they are there, us unknowledgeable bike owners will probably never know.

My feeling is they are there for pressure or moisture relief.

[Pluggy]

The holes in that "pinion cup" allow air to escape when the driveshaft splines, coated with grease, are inserted into the cup.  If the cup were fully closed, the assembly would be like a piston.  The air in the cup would not compress much and the grease would be forced backwards out of the cup. 

Those old BIC ballpoint pens had a little hole in the barrel for the same purpose.  To let air excape when the pen parts were assembled. 

[98valk]

It's obvious the final drive and rear pinion cup are interrelated for some reason, otherwise why would Mother Honda go through the expense of drilling the two holes in the cup.

There is also one in the swingarm I discovered years ago.  Could be more, but only one is visible.

Why they are there, us unknowledgeable bike owners will probably never know.

My feeling is they are there for pressure or moisture relief.

same thing with the FJR1300, weep hole in swing arm and why.
https://www.fjr-tips.org/maint/spline/SkooterG/coupling101.html