Driven Splines wear at 160k miles

[John Galt]

Hopefully the right place for this post.

I used to read a lot of posts about final drive spline wear and concerns.
This is a reference post of my rear wheel's driven splines at 160k miles.

All maintenance is by me, a non-pro but lifelong self vehicle maintainer.
I always wipe and refresh the moly paste on both sides splines at each tire change only; typical 15k miles, but last two changes at 30k miles due to darkside tires.

Just on the latest tire change, I completely cleaned the splines to remove all traces of old paste and applied all fresh.
Also just this time, my one small tube of Honda paste finally ran out. That is for all tire changes from 13k miles to now.

Attached a couple of pictures of the clean splines, from this latest change.
A sharp professional eye may spoy something, and I think I could see a small mark, but I do not see anything that could be called wear.
I will not worry about splines anymore.

 

[W0QNX]

Those look great. You've cared for them well. Mine went to 340,000 something before I was concerned or had wear of maybe 30%. I've suggested TS70 moly paste several times.

FYI there is wear visible. The bottom surface of the splines show in my estimation about .005" to .010". Keep them filled with paste and ride it.

Just to have a picture I made this up. If there was no wear the area between the arrows would have some machine marks or a good flat surface. There is a small amount of wear.

Nothing wrong with some wear, it is a wear item.

 

[John Galt]

Those look great. You've cared for them well. Mine went to 340,000 something before I was concerned or had wear of maybe 30%. I've suggested TS70 moly paste several times.

FYI there is wear visible. The bottom edge of the splines show in my estimation about .005" to .010". Keep them filled with paste and ride it.

Just to have a picture I made this up. If there was no wear the area between the arrows would have some machine marks or a good flat surface. There is a small amount of wear.

Nothing wrong with some wear, it is a wear item.

Thank you, John O!
Hoped some sharp eye would review and advise.
I see it now. Just glad to confirm it is so minimal.
I bought the ST to go for at least 250k........

 

[bdalameda]

I agree these look just fine.

 

[Mr.E]

I found similar wear and thought it was too worn so I replaced both the hub unit and final drive diff.
To be honest, I didn't find much difference afterwards when checking the backlash movement on the rear tyre ~ about 8mm (5/16")
You need to feel (and possibly hear) the backlash with everything warmed up after a short ride.
Would be good to see if we all have about the same 8mm...

 

[motornut]

Out of curiosity how did the rubber damper look after all that mileage

 

[mjc506]

Is that backlash just in the FD splines? Or including the gearbox/UJ/pumpkin too?

 

[SMSW]

Also just this time, my one small tube of Honda paste finally ran out.

There are a couple of threads discussing moly paste. Consensus seems to like Locktite 8012. See posts 266 to 268 in the thread below. Heck, read the whole thing.

M77 Replaces Moly 60- Apparently So | Cleaning, Oil, Maint.

At this point I don’t know what Larry recommends, but my next splines moly will be the LocTite 51048 paste. Still have some Honda Moly 60 though... John I checked over the Valkyrie forum too, and seems like they have the same experience (bad) with the Honda M77 Moly... and also going with the...

www.st-owners.com

Another paste that some guys like, but the 8012 is more popular, more widely available (or was) and I think cheaper:

TS-70 Moly Paste With 70% MoS₂

www.tsmoly.com

 

[Mr.E]

Is that backlash just in the FD splines? Or including the gearbox/UJ/pumpkin too?

I think that question's for me Matt?
It's just the final drive splines we're interested in on this occasion and I'm unsure of any wear limit measurements available for this - so sitting down next to the wheel, very carefully move the wheel back & forth with both hands - you can feel the free movement before it's taken up with slack in the rest of the drive system (bevel, shaft UJ etc.), it should also very quietly clunk at the same time, as mentioned, the bike drive system needs to be warm as cold diff oil removes the ability to check any real free movement.
This is the only easy method I can think of for repeat and routinely checking the spline wear as time goes by.
By the way, my ST had done 59k miles.

 

[mjc506]

Sorry, yes, thanks

Gotcha. Yeah, (my) complete drive-train lash is much more than that of course. I assume most of it is in the gearbox, but there's quite a few gears meshing between the crankshaft and rear wheel!

 

[playfair]

Thanks for your spline update! Some of the teeth look like they have no wear, so there's likely a normal bit of runout. Would say you're finally broken it
My take from this post is the spline doesn't need to be meticulously cared for if you're goal is only 150k miles