C-14 Final Drive Pinion Bearing "play" Tolerance?

[Rembrant]

Hello Folks,

I just finished putting my final drive assembly back together with new inner and outer lip seals, roller bearing, and outer O'ring. Everything looked good inside, and the spline drive is nice and tight and smooth to operate.

Today, I pulled the drive shaft to inspect and clean/re-lube the splines, etc. The drive shaft and everything appear to be just fine. However, I noticed that there is a little "play" in the pinion bearing(s), and I can't find anything in the FSM with regards to an OEM tolerance, or service spec.

With a dial indicator on the end of the input spline socket, I'm reading approximately 0.010" movement side to side. The lip seal appears to be ok as there are no signs of leakage, but I kind of expected the input socket/pinion shaft to be rigid, with zero play as it were?

Does anybody have any expereince with this? Is this movement normal, or would it be normal on an '08 C-14 with 20,000 miles on it?

I'm leaving on an 8,000 mile trip in just a few days, so perhaps I'm worrying too much, but I'd love to hear any ideas or input if you've worked on this before.

Thanks,
Rem ;D

 

[Fred H.]

Which bearing did you replace?

Did you check the backlash?

 

[Rembrant]

Which bearing did you replace?

Did you check the backlash?

I changed the roller/needle bearing that's inside the final drive hub assembly. It had to be removed to change the inner lip seal...the one that's just inside the left hand side of the assembly...on the left end of the axle. The larger ball bearing can't be changed by itself...you have to replace the whole ring gear as an assembly.

I re-installed the ring gear using the same shim that was in there, so I didn't alter the backlash in any way. It should be fine, I assume...there was nothing wrong with the bearing, I only changed it because I had to remove it to get to the seal.

According to the FSM, you can reinstall using the original shim, assuming that nothing else has changed.

It's the pinion bearing that feels a little loose to me, and I didn't touch anything on it, I only removed and re-installed the drive shaft for maintenance purposes.

 

[Fred H.]

Hmmm.....

Did you check it before you took it apart to see how tight it was? I guess if oil isn't leaking past the seal, it's probably ok. I assume you got the pinion gear nut fully tightened down on the sliding joint, and didn't forget the washer, right?

 

[Rembrant]

Did you check it before you took it apart to see how tight it was? I guess if oil isn't leaking past the seal, it's probably ok. I assume you got the pinion gear nut fully tightened down on the sliding joint, and didn't forget the washer, right?

No, and no...lol.

I only changed the bearing in the picture below:

I didn't touch the pinion nut, I only slid the drive shaft and spring out, cleaned and re-lubed the splines, and re-installed. I checked with a motorcycle mechanic freind, and he said the same thing...if the seal isn't leaking, and the bearing still feels smooth to rotate, then it's likely just normal wear for a bike with 20K on it. It's all back together now, so I'm hoping it's fine, and I'll check it again when I get back from my trip, and see if it is the same, or worse. If possible, I'd like to leave it until the winter.....I'll have a few months of "downtime" to properly service it...lol. To be honest, I'm not worry about the bearing, or the seal for that matter....I'm only worried that if it gets bad enough, it will ruin the ring and pinion gears.

 

[B.D.F.]

There should not be any play in the pinion gear and certainly not ten- thousandths of an inch. Both the pinion and ring gears must be held very rigidly to force them to make contact in a specific area of the gear tooth; if either one was loose then a proper pattern would be impossible to achieve. There are two bearings that support and position the pinion gear, a needle roller bearing at the front and a large deep- groove bearing behind the gear teeth, on the pinion body. The part you are measuring is the spline joint for the driveshaft but it should be held in position very rigidly once the pinion nut is tightened.

Are you sure it is actually play or just runout? Either one is less than the best but side- to- side play is really unacceptable.  I would suggest tracking down the source of this movement and eliminating it before riding the bike again.

Brian

Hello Folks,

I just finished putting my final drive assembly back together with new inner and outer lip seals, roller bearing, and outer O'ring. Everything looked good inside, and the spline drive is nice and tight and smooth to operate.

Today, I pulled the drive shaft to inspect and clean/re-lube the splines, etc. The drive shaft and everything appear to be just fine. However, I noticed that there is a little "play" in the pinion bearing(s), and I can't find anything in the FSM with regards to an OEM tolerance, or service spec.

With a dial indicator on the end of the input spline socket, I'm reading approximately 0.010" movement side to side. The lip seal appears to be ok as there are no signs of leakage, but I kind of expected the input socket/pinion shaft to be rigid, with zero play as it were?

Does anybody have any expereince with this? Is this movement normal, or would it be normal on an '08 C-14 with 20,000 miles on it?

I'm leaving on an 8,000 mile trip in just a few days, so perhaps I'm worrying too much, but I'd love to hear any ideas or input if you've worked on this before.

Thanks,
Rem ;D

 

[Fred H.]

Brian brings up a good point about the gear contact between the pinion and ring gear. You may find excessive back lash and/or bad wear on the gears over time if this is left unchecked.

It would be interesting to do that same measurement on another bike and see what it is.

 

[Rembrant]

There should not be any play in the pinion gear and certainly not ten- thousandths of an inch. Both the pinion and ring gears must be held very rigidly to force them to make contact in a specific area of the gear tooth.

Brian, thanks for the reply, you have confirmed my concern...lol. While I'm not a motorcycle mechanic, I am an industrial mechanic, and I too thought that it was unacceptable.

Are you sure it is actually play or just runout? Either one is less than the best but side- to- side play is really unacceptable.  I would suggest tracking down the source of this movement and eliminating it before riding the bike again.

Yes, it's actually side to side, or up and down movement. The runout is fine.

In the defence of the final drive, my measurement isn't entirely acurate. My dial indicator and base was sitting on the floor, not mounted on the final drive where it would have to be to get an acurate measurement. When I was moving the pinion to check the "play" via the dial indicator, I could also have been moving the whole final drive assembly as well, although I tried not to. In any case, there is definitely movement there....the 0.010" just might be slightly more than actual if you get my drift?

I'm leaving on a trip in four days, so I don't have time to repair it, or the parts. I'm going to bring the tools I need to inspect it while traveling, and causing further damage is a risk I'll have to take. Best case scenario, it'll stay the same...worse case, it will start to get noisy, or leak, or I'll be able to tell by inspecting it that it's getting worse.

On the up side, the oil I drained out was clean, and the ring and pinion teeth look like they're brand new. There is no evidence of any abnormal wear at this time. I even have a magnetic tipped drain plug in there, and it was clean as well.

I'm bringing the necessary tools with me for service, as well as enough oil to do a change on the final drive. If it doesn't get any worse, I'll repair it properly when I get back. If I end up having to service it on the road, well, I guess I'll do that too...lol.

Thanks for your input guys, it's very much appreciated.

Rem ;D

 

[Rembrant]

Hey Fred/BDF,

So, I made it back from the trip safe and sound with no issues...my '08 Connie performed flawlessly and the final drive gave me no grief. We did 8300 miles in 14 days, and just got home last night. (The bike now has 30,000 miles on it)

I changed out the final drive oil, and it was pretty dark...I'm not sure what is normal and what isn't...I only bought the bike last fall, and switched the final drive oil immediately to Amsoil "Severe Gear" 75w90, and with the final drive seal failures, I've never been able to put a huge amount of miles on the oil to see what it *normally looks like at a regular change interval.

There was a light black film on the magnetic tip of the drain plug, and everything looks clean inside the filler hole, but the oil was pretty dark.

What have you guys seen usually? Is it typical for the oil to be pretty dark/dirty with 8k on it? I figured if there was any abnormal wear taking place, I'd see more fuzz on my drain plug magnet.

Thanks,
CW

 

[Fred H.]

My oil comes out about the same as what you describe. I guess the only way we will know if this is normal or not is if someone else does the same measurement as you did. My gut feeling is that it's normal on this bike, but I could be wrong.

 

[ndmiller]

My oil comes out about the same as what you describe. I guess the only way we will know if this is normal or not is if someone else does the same measurement as you did. My gut feeling is that it's normal on this bike, but I could be wrong.

I can swear someone knowledgable posted the oil comes out dark due to the assembly lube with Moly in it.  I thought it was fred or bob, maybe this forum or the other one.  Obviously I could be wrong....

 

[Fred H.]

My oil comes out about the same as what you describe. I guess the only way we will know if this is normal or not is if someone else does the same measurement as you did. My gut feeling is that it's normal on this bike, but I could be wrong.

I can swear someone knowledgable posted the oil comes out dark due to the assembly lube with Moly in it.  I thought it was fred or bob, maybe this forum or the other one.  Obviously I could be wrong....

Yes, the first change comes out real dark because of the moly based assembly grease they use when they assemble the rear drive. This is normal. The second and third changes will be a little lighter in color.

 

[ndmiller]

My oil comes out about the same as what you describe. I guess the only way we will know if this is normal or not is if someone else does the same measurement as you did. My gut feeling is that it's normal on this bike, but I could be wrong.

I can swear someone knowledgable posted the oil comes out dark due to the assembly lube with Moly in it.  I thought it was fred or bob, maybe this forum or the other one.  Obviously I could be wrong....

Yes, the first change comes out real dark because of the moly based assembly grease they use when they assemble the rear drive. This is normal. The second and third changes will be a little lighter in color.

Fessik, you did somting right!

 

[B.D.F.]

The dark material is steel fines caused by normal wear between the gear teeth. Nothing to worry about.

The easiest way to check the condition of a final drive is to look at the ring gear through the lube fill hole- there should be a shiny wear patch on each tooth, somewhere near the middle of the tooth. A bright, shiny and even surface is what should be there. Any deep grooves, finer grooves in an overall dull patch and especially any evidence of material tearing out are bad signs. Then again, if any of that were happening, there would be visible pieces of metal in the old lube.

It sounds like your drive is wearing in fine and should outlast the bike itself.

Brian

Hey Fred/BDF,

So, I made it back from the trip safe and sound with no issues...my '08 Connie performed flawlessly and the final drive gave me no grief. We did 8300 miles in 14 days, and just got home last night. (The bike now has 30,000 miles on it)

I changed out the final drive oil, and it was pretty dark...I'm not sure what is normal and what isn't...I only bought the bike last fall, and switched the final drive oil immediately to Amsoil "Severe Gear" 75w90, and with the final drive seal failures, I've never been able to put a huge amount of miles on the oil to see what it *normally looks like at a regular change interval.

There was a light black film on the magnetic tip of the drain plug, and everything looks clean inside the filler hole, but the oil was pretty dark.

What have you guys seen usually? Is it typical for the oil to be pretty dark/dirty with 8k on it? I figured if there was any abnormal wear taking place, I'd see more fuzz on my drain plug magnet.

Thanks,
CW

 

[anthony2008]

as for lube i run --- Royal Purple SYNTHETIC OIL == max-gear SAE 75w-140  drain out you old or even new gear lube and try this stuff it is like butter smooth

 

[fretka]

My '09 with 6k miles has no detectable lash in any axis.

 

[Fred H.]

With a dial indicator on the end of the input spline socket, I'm reading approximately 0.010" movement side to side. The lip seal appears to be ok as there are no signs of leakage, but I kind of expected the input socket/pinion shaft to be rigid, with zero play as it were?

Does anybody have any expereince with this? Is this movement normal, or would it be normal on an '08 C-14 with 20,000 miles on it?

I know it's been awhile since you asked this question, but I was replacing my tires yesterday and I decided to pull out the rear drive shaft and lube the front spines on it. When I put it back together I checked the feel of the input spline for any movement and I could just barely detect a bit, probably around a couple thousandths or so. It felt like it was pushing on the rubber seal and had just a tiny bit of movement in it from left to right, but I didn't feel any in the vertical axis. It was such a small amount I could barely feel it. I didn't bother to put a dial indicator on it.