Final Drive Pinion Cup - Moly, Gear Oil, etc. (Wing World Tech Editor Reply)

[vic]

The subject of why the 2 holes are there in the pinion cup had me really wondering what the story really is......some say they are there for gear oil to lube the splines in the cup and on the shaft, and the other major theory is that they are there to equalize pressure,  etc.  Both major explanations made some sense but the subject has never really been settled.   Turns out, both theories are valid.....the gear-oil-lubing-the-splines theory is accurate because that was Honda's original intent.   However, Honda later found out that these holes letting in gear oil didn't always work as planned and ended up putting out a Technical Service Bulletin recommending that the pinion cup and splines are lubricated with moly at regular intervals.   That explains why some Valk owners find their pinion cups and splines bathed in gear oil and others, like me, have never seen a drop of gear oil in their pinion cup.  

So I decided to write to Stu Oltman, Technical Editor for Wing World Magazine.  If anybody knows the inner workings of Hondas, it would be him.  Below is my e-mail to him followed by his reply to me which I received today.

Hello Stu:

I'm hoping you can answer a question that has been debated by members of the Valkyrie community probably since the Valkyrie was first marketed by Honda.  In the Valkyrie's pinion cup, there are what appear to be two small machined holes....each at different angles.  Some believe these holes are meant to allow gear oil into the pinion cup via centrifugal force to lubricate the end of the drive shaft inside the pinion cup.  The other camp believes that these holes are there for another purpose such as to stabilize the pressure inside the pinion cup or are just there for a purpose other than to allow gear oil inside the pinion cup.  Honda's maintenance manual requires that when servicing the rear end, moly paste is used on the final drive/wheel splines and moly grease is used on the ends of the drive shaft and inside the pinion cup.  If the two holes I mentioned previously were meant to allow gear oil into the pinion cup, I would think Honda would have issued a warning not to block these holes with too much moly grease so as not to impede the flow of gear oil into the pinion cup.  On the other hand, Honda may have overlooked this point.  I assume that the GL1500's rear drive was similar to the Valkyrie's so I thought you may have some knowledge of what these two "mysterious" holes are there for.  Thank you in advance for any information you may have on this topic.

Victor Smith
GWRRA# 164606



From: "Wing World Technical Dept." <wingworldtech@cox.net>
To: VCS <v102071@inreach.com>
Sent: Mon, Jun 3, 2013 13:11:35 GMT+00:00
Subject: Re: Valkyrie Pinion Cup Question


Vic,
The holes were for the purpose of allowing gear oil to lube the splines in the cup and on the shaft. The Moly grease on re-assembly was for start-up lubrication – after which, gear oil would supposedly find its way in and eventually wash out the grease. If there were no service operations to be performed which required R&R of the final drive, those splines were intended to not ever need manual lubrication. But that's not how it turned out. Honda now recommends manually lubing those splines with Moly 60 at 16,000 mile intervals.

Stu

[gordonv]

Thank you vic, for finding an answer from someone who seems to "know" what the answer is. I'll check my Wing Worlds and see if I see this posted there.

Maybe one reason why when I talk to my GW buddies, they don't seem to know anything about checking the pinion cup, or even loosening off the 4 nuts from the swing arm.

Of cource, my GL1500 is only an 88' and there is a little differance over the 90'-00' models.

[signart]

That makes more sense than anything I've heard. I think the red rusty pc syndrome we've been witnessing in recent threads after several maintenance intervals with good results then all of a sudden rusty powder prove this.
My theory is grease, no matter how much grease, on occasion is washed out of the pinion cup & shaft by gear oil. But then the gear oil somehow stops reaching the pinion cup resulting in the red powder syndrome.

[Mallett]

Thanks Vic for the info. I replaced my rear tire yesterday. My shaft, pinion cup & final drive spline looked great. I'm one of the believers that the final drive oil does oil the pinion cup but I also believe in putting a c-v joint moly lube on mine before reassembling...here is a pic of my shaft when I pulled it out yesterday....sloppy wet with final drive oil.....

[vic]

Hello Mallett.  Your splines on the drive shaft look well lubed and the gear oil on them is exactly what Honda intended.   Looking back on this issue, that's why Honda called that seal on the drive shaft, an "oil seal" instead of a "grease seal".  Unfortunately, the pinion cup holes haven't always worked as designed so "Plan B" is to lube with moly as you and everyone else has been doing.

[BonS]

I've said it before but it bears repeating. A pfffft of air into the two lubricating holes ensures that they're clear an open. Simply wiping around with rags and Q-tips may just push gunk deeper into the holes and plug them up while they look clean on the outside.

[Daniel Meyer]

From: "Wing World Technical Dept." <wingworldtech@cox.net>
To: VCS <v102071@inreach.com>
Sent: Mon, Jun 3, 2013 13:11:35 GMT+00:00
Subject: Re: Valkyrie Pinion Cup Question


Vic,
The holes were for the purpose of allowing gear oil to lube the splines in the cup and on the shaft. The Moly grease on re-assembly was for start-up lubrication – after which, gear oil would supposedly find its way in and eventually wash out the grease. If there were no service operations to be performed which required R&R of the final drive, those splines were intended to not ever need manual lubrication. But that's not how it turned out. Honda now recommends manually lubing those splines with Moly 60 at 16,000 mile intervals.

Stu

[doubletee]

Fantastic info that, for me anyway, clears up the confusion. I have been really curious about this subject. I can sleep now that it's been answered. 

[Farther]

I find it interesting that some members were the source of the original information about the purpose of the holes but were not believed until an outside expert was consulted.  If memory serves me Daniel Meyer is a former certified Honda tech and his advice was falling on deaf ears.

[doubletee]

I find it interesting that some members were the source of the original information about the purpose of the holes but were not believed until an outside expert was consulted.  If memory serves me Daniel Meyer is a former certified Honda tech and his advice was falling on deaf ears.

Agreed. I had no reason to doubt Daniel, but the part that finally sold it for me is, "Honda now recommends manually lubing those splines with Moly 60 at 16,000 mile intervals."

[Jabba]

I've said it before but it bears repeating. A pfffft of air into the two lubricating holes ensures that they're clear an open. Simply wiping around with rags and Q-tips may just push gunk deeper into the holes and plug them up while they look clean on the outside.

I always PULL the pinion cup and clean it REAL good with Dawn Dish Soap and hot water, till it's SQUEAKY clean.  They dry it with heat before lubing and reassembling.  There is ZERO chance I "missed" getting the holes clear.  I PROMISE.

The sometimes it fails... explanation is better than any other I have heard.  I will keep doing mine annually from now on.  And some moly grease is a good back-up plan.

Jabba

[98valk]

remember grease is nothing but oil suspended in a carrier. over time and use the oil does migrate out of the carrier part of the grease. so what is being seen and assumed to be gear oil might only be the oil from the grease.

[MP]

remember grease is nothing but oil suspended in a carrier. over time and use the oil does migrate out of the carrier part of the grease. so what is being seen and assumed to be gear oil might only be the oil from the grease.

Gear oil has its own smell.  You cannot confuse the smell with grease smell!

MP

[Patrick]

I find it interesting that some members were the source of the original information about the purpose of the holes but were not believed until an outside expert was consulted.  If memory serves me Daniel Meyer is a former certified Honda tech and his advice was falling on deaf ears.
end quote

Good info falling deaf ears ?! This isn't the first time and probably won't be the last.

[signart]

Don't doubt what the holes are suppose to do, but why doesn't it do it every time? Otherwise, there would be no need to service the p/c at the intervals some are having issues with.
What's the solution, possibly overfill the gear oil a measured amount?
Seen several reports of bone dry splines & cup, just wondering why that would ever happen?

[Daniel Meyer]

Don't doubt what the holes are suppose to do, but why doesn't it do it every time? Otherwise, there would be no need to service the p/c at the intervals some are having issues with.
What's the solution, possibly overfill the gear oil a measured amount?
Seen several reports of bone dry splines & cup, just wondering why that would ever happen?

The entire pinion joint is sort of an engineering shortcut on the Valk...a cheat...not a good design in my opinion.

It is (or was) not an item that was supposed to need service. Obviously it does. The short of it is, if it never gets serviced, it will fail. Generally around the 50-70k mile mark.

Most that end up dry were a long term kind of thing. I've no real data on the short time ones...though I've an idea...I'd need to discuss with someones that failed in person with parts to talk about it.

The solution is to inspect, clean, lube every 10k miles or so (that's when I do my splines as well). I use regular ol wheel bearing grease, and a light coat of that. I think the pastes in that location are a recipe for failure. This is not a spline...it's a joint with some play to allow for alignment (a bearing on the back of the swing-arm would have been SO much better). Anyway, it does have some movement and generates considerable heat. Once it starts to go...it goes fast.

You can probably get away with 15-20k miles between shots, but it's a five minute thing if you're already changing a tire or doing the splines.

I do the same procedure every time. It works every time. On every Valk I've worked on (a few).

It's much easier to explain in person, with parts on hand. As I've said, come to Inzane. I'll show you.

[Squealy]

I've no real data on the short time ones...though I've an idea...I'd need to discuss with someones that failed in person with parts to talk about it.

You want my drive shaft and pinion cup that failed at 7,000 miles? I have them, I'll be at Inzane (for some part of it anyway)....

[Daniel Meyer]

I've no real data on the short time ones...though I've an idea...I'd need to discuss with someones that failed in person with parts to talk about it.

You want my drive shaft and pinion cup that failed at 7,000 miles? I have them, I'll be at Inzane (for some part of it anyway)....

Yeah, look me up at any of the tech sessions. 

[doubletee]

Don't doubt what the holes are suppose to do, but why doesn't it do it every time? Otherwise, there would be no need to service the p/c at the intervals some are having issues with.
What's the solution, possibly overfill the gear oil a measured amount?
Seen several reports of bone dry splines & cup, just wondering why that would ever happen?

The entire pinion joint is sort of an engineering shortcut on the Valk...a cheat...not a good design in my opinion.

It is (or was) not an item that was supposed to need service. Obviously it does. The short of it is, if it never gets serviced, it will fail. Generally around the 50-70k mile mark.

Most that end up dry were a long term kind of thing. I've no real data on the short time ones...though I've an idea...I'd need to discuss with someones that failed in person with parts to talk about it.

The solution is to inspect, clean, lube every 10k miles or so (that's when I do my splines as well). I use regular ol wheel bearing grease, and a light coat of that. I think the pastes in that location are a recipe for failure. This is not a spline...it's a joint with some play to allow for alignment (a bearing on the back of the swing-arm would have been SO much better). Anyway, it does have some movement and generates considerable heat. Once it starts to go...it goes fast.

You can probably get away with 15-20k miles between shots, but it's a five minute thing if you're already changing a tire or doing the splines.

I do the same procedure every time. It works every time. On every Valk I've worked on (a few).

It's much easier to explain in person, with parts on hand. As I've said, come to Inzane. I'll show you.

Great.   I've got 27,000 on mine and unless the previous owner maintained it or had it done, it's never been done.      I'm afraid to look, now.

[Daniel Meyer]

Great.   I've got 27,000 on mine and unless the previous owner maintained it or had it done, it's never been done.      I'm afraid to look, now.

You're probably good, but give it a check anyway. It's cheap/easy fix...

[Earl in Pensacola]

The original complete "rear-end" on my '97 Tourer had absolutely nothing done to it for 83K!!!  The bike is now at 268K. I had always taken my new bike to a dealership for all tires & changes.  The most anyone of them had done was wipe clean the one end of the shaft, put a little grease on it and finish the tire mounting.  At 83K, Mother Honda paid to have the entire rear-end innards replaced under my extended warranty, shaft, bearings, gears, seals everything. That's when I started learning about "servicing the rear-end", even though I still depended upon various so-called mechanics to do it right, one of which was right here in Pensacola.  It cost HIM $175.00 to pay for me having to have Honda dealership correct what he had incorrectly done.  I finally met Chris in Crestview Fl. and really learned what should be done, how and when to do it.  The problem now-a-days is, I'm no longer strong enough to do the heavy stuff, but I sure know HOW to do it and when.  By-the-way it's my bike that Chris is referring to when he spoke of my going 25K before checking the rear-end for lube etc. It was still very well lubed.  It was chris that had done the previous service work, so I can tell you that the way HE does it, IS the way to do it.  I'll be going for wearing out TWO rear tires before pulling it all apart again.  That would be something like 36K !!

[The emperor has no clothes]

Don't doubt what the holes are suppose to do, but why doesn't it do it every time? Otherwise, there would be no need to service the p/c at the intervals some are having issues with.
What's the solution, possibly overfill the gear oil a measured amount?
Seen several reports of bone dry splines & cup, just wondering why that would ever happen?

The entire pinion joint is sort of an engineering shortcut on the Valk...a cheat...not a good design in my opinion.

It is (or was) not an item that was supposed to need service. Obviously it does. The short of it is, if it never gets serviced, it will fail. Generally around the 50-70k mile mark.

Most that end up dry were a long term kind of thing. I've no real data on the short time ones...though I've an idea...I'd need to discuss with someones that failed in person with parts to talk about it.

The solution is to inspect, clean, lube every 10k miles or so (that's when I do my splines as well). I use regular ol wheel bearing grease, and a light coat of that. I think the pastes in that location are a recipe for failure. This is not a spline...it's a joint with some play to allow for alignment (a bearing on the back of the swing-arm would have been SO much better). Anyway, it does have some movement and generates considerable heat. Once it starts to go...it goes fast.

You can probably get away with 15-20k miles between shots, but it's a five minute thing if you're already changing a tire or doing the splines.

I do the same procedure every time. It works every time. On every Valk I've worked on (a few).

It's much easier to explain in person, with parts on hand. As I've said, come to Inzane. I'll show you.

Great.  ( I've got 27,000 on mine and unless the previous owner maintained it or had it done, it's never been done.      I'm afraid to look, now.)

i never checked mine till I read about jabbas & squeallys issuses recently. That was at 45k and it looked great so chances are yours is good