Rear Drive Train Maintenance

[Valkpilot]

I'm getting ready for a long trip and it was time to maintenance the rear end.  I'm also putting in a new u-joint as a precautionary measure, but as you can see below, probably not necessary.

Images are from a 1998 Standard with 58,000 miles, 25,000 of which are Dark Side miles.

Daniel, whattaya think?


Engine output shaft:



This u-joint has not been wiped off.  It came out of the boot looking like this.  There is zero play.


U-joint splines:


Splines at the ther end of the u-joint:


Drive shaft splines, u-joint end:


Drive shaft splines, pinion cup end:


Pinion Cup (weeping drive oil after cleaning holes):


Drive gear splines in the pumpkin:


Driven hub:


Driven hub:

[Daniel Meyer]

Looks good! Put her back together right and she'll be good for another round!

(the 4 pumpkin nuts last)

[Ghillie]

WOW, doesn't look like any significant wear on anything. Hope mine comes apart looking that good.

[Valkpilot]

Looks good! Put her back together right and she'll be good for another round!

(the 4 pumpkin nuts last)

I learned the pumpkin nuts trick a long time ago!  I honestly don't see how you wrestle the sumbitch in place without doing that anyway.  I remove the shocks, lift the bike, then put a car jack under the rear tire and lift it so the axle clears the exhaust.  Goes back in the same way and being able to adjust the height of the tire/wheel with the floor jack makes a world of difference when you're working alone.

This is the 4th time I've had the rear end apart (2 times in 3 weeks in December last year; once to do the rear tire, then again to put in new rear bearings.  Every other time, the maintenance has been done by a dealer when putting on MC tires.

Bottom line: except for one 19k mile stretch (I was a bad boy with my first DS tire), the rear end has been serviced every 8,000 to 10,000 miles, mainly because that's all I can get out of an MC tire.

This is the first time the U-joint has seen the light of day since the factory though.  I'm pretty happy with that.

[Valkpilot]

WOW, doesn't look like any significant wear on anything. Hope mine comes apart looking that good.

I'm ready to help with yours when you're ready.

[T-Roy]

Don't forget to check the rear wheel bearings !!

[Valkpilot]

Don't forget to check the rear wheel bearings !!

Wow. Tell me that's a fake and you stuffed pea gravel in there.

Did mine about 6 months ago.  Felt smooth until you loaded them up.  I could feel it in the corners.  Nothing like yours though.

[T-Roy]

The good news is, I finally figured out why my ride wasnt as smooth as usual!

[Valkpilot]

The good news is, I finally figured out why my ride wasnt as smooth as usual!

How long did it take to notice?  Did they get that bad real suddenly?

[T-Roy]

Its a long story, but I've been feeling the problem a year and a half and couldnt find the problem.

[Valkpilot]

Mine was similar.  I replaced shocks (needed anyway) and suspected the swing arm before figuring out the real problem.

[Valkpilot]

Tore down the rear end on the '98 the other day for maintenance.

10,000 miles since this thread and there's no change in the look of the parts.

Lube 'em with the right stuff, lube 'em on time, and follow Daniel's advice on reassembly (pumpkin nuts last) and your rear end won't bite you in the rear end.

[Valkpilot]

Tore down the rear end on the '98 the other day for maintenance.

10,000 miles since this thread and there's no change in the look of the parts.

Lube 'em with the right stuff, lube 'em on time, and follow Daniel's advice on reassembly (pumpkin nuts last) and your rear end won't bite you in the rear end.

Serviced it Saturday at 72,000 miles when I mounted a new Altimax and chrome wheels.  Everything still looks like the original pictures.  Changed the pumpkin oil and the old oil looked like it was being poured out of the bottle instead of the final drive.

[Valkpilot]

On Saturday I decided to service the rear drive.  Buzzkill decided he could pass on VD and came over to help.  

At 83,500 miles:

Driven (star hub) spines (the icky fiber-looking things are from the cotton swabs Buzzkill was cleaning with):


Drive (pumpkin) splines:


Drive shaft pinion splines:


Pinion cup splines:


The pinion came out nice and wet and gooey:


We also found that the "elusive third o-ring" was broken, so the service was timely.


I used the RedEye polyurethane rings this time.  I'll have to pull the rear wheel apart before June to mount a new rear tire, so will have a chance to assess them at that time.

We also pulled the u-joint.  It was solid.  While we cleaned everything else, I soaked the u-joint boot in silicone spray and let it sit.  It went back on really easily.

Oh yeah...

It's well known that the "thunk" in the front end when you brake sometimes is due to the fact that the calipers "float" on pins attached to the caliper mount.  Well, that's true for the rear brake as well.

While everything was apart I decided to clean the pistons and replace the pads.  I had purchased Interstate pads because they're a little beefier.  We went to put everything back together, they wouldn't fit, even though the pistons were fully retracted.  

Grump, grump, grump, off to Buzzkill's house to compare the pads to a new set he had.  

Identical.  Phooey.

So, as I kept wrestling, I noticed a gap between one of the caliper mounting pins and its rubber boot.  Hmmmm, thinks I, this should be moving and it's not.  So, I dismounted the caliper from the mount and found, sure enough, one of the pins was frozen in place.  A little sandpaper, a little grease in the boot, and magically I've got a floating caliper again.  The assembly practically fell into place after that.

Something to keep in mind when you do your next brake job.  The rear caliper is out-of-sight, out-of-mind if you've got bags, so it doesn't always get the attention it needs.

[HayHauler]

Good write up and great hi-res pics.  Yours looks better than mine.  I will be replacing the drive shaft and pinion cup before the summer riding season, at tire replacement as with you. 
125k now and the pinion splines showed more wear than I am comfortable with. 

Hay
Jimmyt

[Disco]

Thanks for keeping this thread alive with another great write-up, Dave.  

As many have seen in the final drive-related posts over the years, or some have experienced firsthand, in the absence of proper periodic maintenance, superior design, manufacture, metallurgy, lubrication, and assembly will literally only get you so far before excessive wear or failure occurs.  If you add properly-performed regular maintenance to the mix, the life of these parts can be extended for who knows how long.  

And, anyone who persists in claiming that the final drive and pinion cup do not communicate through the two holes is proved wrong by the picture of the sopping wet driveshaft.  

[Daniel Meyer]

 

That's a heck of a hi-res pic! Pretty sure I got grease on my nose just looking at it!

[Valkpilot]

That's a heck of a hi-res pic! Pretty sure I got grease on my nose just looking at it!

Believe it or not, that was taken with my phone camera. 

[heavyd]

The repeated mention of the 4 pumpkin nuts reminded me of a question I've had for a long time. What is the secret to getting a torque wrench on all of those nuts? I have tried every combination of extensions and universals I have and I can't find anyway to get them all.

[Jess from VA]

Quarter inch sockets.... and you can get a 1/2 or 3/8 (depending on your torque wrench) to 1/4 inch conversion step-down socket.  Except for the big bolts, quarter inch tools were made for bikes.

http://www.sears.com/craftsman-1-4-to-3-8-in-socket-adapter/p-00904257000P

[Valkpilot]

The repeated mention of the 4 pumpkin nuts reminded me of a question I've had for a long time. What is the secret to getting a torque wrench on all of those nuts? I have tried every combination of extensions and universals I have and I can't find anyway to get them all.

Well...uhm...er...I don't torque those.  I just snug them up good.  Somehow, they always seem to be tighter when I go to take them off next time.

[Firefighter]

Hey Valkpilot, You said your wheel bearings felt good until you loaded them up. For 5000 miles or so when I am in a parking lot running slow and making very hard over turns, I can feel a roughness in right or left turns. I don't ever feel anything on the road or normal riding. Is that what you mean by loaded?

I ordered front and rear bearings and when I did rear maintenance a couple thousand miles back I couldn't feel any roughness in the bearings (moving them by hand) so did not replace them. Checked front bearings also at that same time. I thought possibly the front tire was causing this rough feeling.
                                 Thanks Firefighter

[Daniel Meyer]

To check the bearings stick the axle just into each one (on one side at at time) and "load it" by pressing down on the end of the axle while rolling it under your palm. Becomes VERY obvious if the bearings are bad.

[Firefighter]

Never thought of that. Used my fingers and used the axle but with no load, Thanks again wont forget that one.  Firefighter

[heavyd]

My front tire is off right now getting a new Avon installed, I checked the bearings and they felt smooth just a little tight and not quite perfect. When I get the rim back I will have to try this axle idea, might save me from pulling the tire in another 3000 km.

[Valkpilot]

Hey Valkpilot, You said your wheel bearings felt good until you loaded them up. For 5000 miles or so when I am in a parking lot running slow and making very hard over turns, I can feel a roughness in right or left turns. I don't ever feel anything on the road or normal riding. Is that what you mean by loaded?

I ordered front and rear bearings and when I did rear maintenance a couple thousand miles back I couldn't feel any roughness in the bearings (moving them by hand) so did not replace them. Checked front bearings also at that same time. I thought possibly the front tire was causing this rough feeling.
                                 Thanks Firefighter

What Daniel said.

The idea is to side load them some.  I push in or pull out while turning them.  If there is too much play in the bearing, they'll bind under that load.

[mike72903]

Lube 'em with the right stuff, lube 'em on time, and follow Daniel's advice on reassembly (pumpkin nuts last) and your rear end won't bite you in the rear end.

Thanks for keeping you maintenance story updated.  Found it very helpful.  From searching the forum I know there are lots of opinions about what "the right stuff" is and was wondering what you use.  Getting ready to do my first rear tire change and rear maintenance on the bike I got from Woody a while back.  Got a big trip coming and naturally want it to be trouble free.
Thanks,
Mike

[Valkpilot]

Lube 'em with the right stuff, lube 'em on time, and follow Daniel's advice on reassembly (pumpkin nuts last) and your rear end won't bite you in the rear end.

Thanks for keeping you maintenance story updated.  Found it very helpful.  From searching the forum I know there are lots of opinions about what "the right stuff" is and was wondering what you use.  Getting ready to do my first rear tire change and rear maintenance on the bike I got from Woody a while back.  Got a big trip coming and naturally hope it will be trouble free
Thanks,
Mike

I basically go by the manual.

For the the drive, hub, wheel assembly splines, o-rings, and thrust washer the manual states a 30% moly paste, with Honda Moly 60 being one of the lubricants which meets the requirements.

I use the Moly 60 or an equivalent.  Some argue that the Honda Moly 60 is not a paste because the moly is in an oil/grease carrier, but it is the high solids content of the moly, not the carrier, that defines it as a paste.

Some also believe that this is not a "wet" enough lubricant and they substitute regular grease or mix grease with the moly paste.  I feel this should not be a concern because moly would protect the splines if it were dry powder.  (It would just be difficult to contiain in the spline joint, so hence the carrier material.)

For the pinion cup, drive shaft, and u-joint splines, the manual recommends 3% moly grease, but most, including me, use a quality waterproof bearing grease such as Belray.  A little goes a long way in these areas --  the recommended amounts are 2 grams or less.  

Another controversy: the manual calls for greasing the rubber seal around the drive shaft that fits in the pinion cup.  The contention is that this collects dirt.  I contend that it helps seal out moisture that might get in the swing arm and migrate to the pinion joint, so I smear it with grease and run my finger round the circumference after it is pressed in place.

I also always disassemble the pinion cup from the final drive.  This allows for thorough cleaning of the pinion cup, including the two holes in the bottom of the cup.  (Too much controversy about their purpose to discuss here, but hardly anyone argues that you shouldn't clean them.)

I clean everything with mineral spirits.  It's a good solvent for the purpose.  But, since doing so risks contaminating the rear drive oil with solvent, I change the rear drive oil at each service.

The main points to me:

• Service the rear drive train often, at least every 10,000 miles (this may be the most important point)
• Lube it correctly
• Replace the o-rings each time (they're cheap)
• Change the drive oil each service (again, not expensive)
• Torque the axle nut before final tightening of the nuts that hold the pumpkin to the swingarm

[mike72903]

Right-o, Thanks.  Bought the Honda 60 Moly last week and found some Belray water proof grease at about the fifth MC service dept I went to today.  Now if Partszilla hadn't shipped my parts to Hawaii I'd be ready to go.

[Valkpilot]

Needed to put a new rear tire on the Valk, so even though it's only been a few thousand miles, I serviced the rear drive.  

At 85,000 miles (all original components):


Drive splines



Star hub.  That polyurethane O-Ring has over 2000 miles on it and looks brand new still.



Pinion splines on the drive shaft



Pinion cup splines

[RainMaker]

Looks great - sure makes a difference when equipment has regular maintenance.