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drive shaft to final drive lube

154048

Atomic City Boxer
I just finished lubing the input splines on my 1980 R100 (45k miles). Pretty straight forward operation. Next I service the final drive.

My question in looking at my Clymers is: They recommend applying a thick coat of 'drive spline lubricant' to the final drive coupling splines and to the drive shaft splines, when I reassemble the two after inspection.

Are these splines not lubricated by the "drive shaft oil"?

Thanks,
Steve in Santa Fe
 
Anytime you are putting splines back together if they are running in gear oil, you should lube them with a grease... insures that they won't be running dry until the gear oil reaches them...in the absence of somebody's better idea, I reckon the exact grease isn't too too critical, as it's true that it will eventually wash out of there, but anything that's gonna work with yer gear lube should work fine... I normally use a red grease or moly grease on my trucks, etc...
 
That is kinda what I was thinking..a little 'hold the fort till the cavalry arrives' thing.
Thanks for the input....
 
The final drive gear lube does NOT lube the drive splines - that's what the seals are for, to keep it OUT (I should know, I hadda replace 'em twice - the seals, I mean). If gear lube gets through to the splines, it's next stop rear wheel - kind of looks like those kids toys that spin a sheet of paper while they squirt paint on it.

You should use the same thing you use to lube the clutch input splines. Me, I use Krytox, but a good moly grease will suffice.

Edit = maybe I misread your message. I am referring to the splines in the drive housing that connect to those in the rear wheel. No longer sure if that's what you were referring to.
 
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Exactly what Clymer manual is being read here? - for what bike? Airhead, right. Gear oil in the driveshaft housing, right?

So gear oil in the transmission. Gear oil in the final drive. Gear oil in the shaft housing? Moly grease on the wheel/final drive splines.

You can slather grease on the driveshaft if you wish, but assuming it is a wet shaft in oil you are gaining nothing. That entire spline will be wet by the time the rear wheel turns 1/3 revolution or so.
 
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I was meaning the location where the drive shaft attaches to the final drive. There is a star (for lack of a better word) shaped gear there that Clymers advises to grease up after re assembly. I have cleaned and greased the wheel/ final drive splines.

Funny thing about needing to replace the seals between shaft and final drive...When I got the bike, the rear wheel and tire was a mess of gear oil. The PO didn't know how to get the bike on the center stand so checked the final drive level while leaning on the side stand...and added fluid accordingly. I was sure that the seal was out, but after I got it home and drained and properly filled the FD, all is well. The overflow came out the 'vent' at top, I guess.

(Fortunately he took the bike to the dealer for regular engine oil and filter changes...I can only imagine what his oil level checking procedures might have been....

Steve
 
I was meaning the location where the drive shaft attaches to the final drive. There is a star (for lack of a better word) shaped gear there that Clymers advises to grease up after re assembly. I have cleaned and greased the wheel/ final drive splines. Steve

I understood what you were saying...the wheel spline is, as has been pointed out, a separate piece...you said drive shaft to final drive, and yeah, that runs in lube, but it was pointed out to me many years ago that it is necessary to grease up splines that run in oil regardless, but the grease material isn't critical...
 
I understood what you were saying...the wheel spline is, as has been pointed out, a separate piece...you said drive shaft to final drive, and yeah, that runs in lube, but it was pointed out to me many years ago that it is necessary to grease up splines that run in oil regardless, but the grease material isn't critical...

Which was what I was perplexed by and don't agree with. It won't hurt, but it doesn't do anything either. If properly filled the oil in the shaft is above the entire splined coupling. So the whole thing is dipped in gear oil. Even if a little low, the whole spline will rotate 3 times or so for every wheel revolution so by the time you get it out of the garage it is well dipped many times.

So what the grease is supposed to be doing escapes me in this application.

There are some splashed applications where it might help but not this one.
 
I think your outside "advice" is mistakenly referring to the rear drive of later airheads..paralever,,and all first generation K bikes.

Those models definitley needed rear spline lube or you had dry gears.

Before paralevers, all airheads were lubed by the swingarm fluid..not grease.
 
I just finished lubing the input splines on my 1980 R100 (45k miles). Pretty straight forward operation. Next I service the final drive.

My question in looking at my Clymers is: They recommend applying a thick coat of 'drive spline lubricant' to the final drive coupling splines and to the drive shaft splines, when I reassemble the two after inspection.

Are these splines not lubricated by the "drive shaft oil"?

Thanks,
Steve in Santa Fe

Steve: I have an '82 r100rt and just saw for the "grease for splines on rear wheel final drive" in my book. How do you grease spines?

Thanks

Bill
 
Steve: I have an '82 r100rt and just saw for the "grease for splines on rear wheel final drive" in my book. How do you grease spines?

Remove the wheel. All will be evident. Clean both sides of the splines. Then apply a good grease, such as Honda Moly 60, to the wheel side, not the drive side. By putting it on the wheel side, you don't force excess grease towards the wheel seal.
 
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