Slack/Noise in Side Gear?

ST1100Y · Nov 13, 2020

Anyone ever had issues with the hyppoid gear at the tranny output?

When picking up my GF's NT700 in January I could feel & hear a slack in the drive-train in response to load changes...
After pulling the rear wheel I also removed the final-drive from the swing-arm but couldn't sense any excessive play or clearance there...
I thought I had fixed this then by replacing the worn hub-dampers & aluminum bushings, of course it has massively improved now, but there is still some metal(?) clacking noticeable...

And if I put the bike on main-stand, so the swing-arm is unloaded & hanging down, run the engine in idle and engage the clutch with 2ng gear to spin the rear wheel, some real clickidy-clack starts...

I plan to pull the swing-arm over the winter to check the U-joint and output shaft but wonder if I'll also need to pull the side gear case while at it... :unsure:

rc_heli_nut · Nov 13, 2020

Recent thread on this:

Questions about the final drive | Drivetrain

Would welcomed any insight on the final drive...specifically the symptoms that indicate it is failing. Long story short..went to change my rear tire (first time since owning the bike) and with the wheel off discovered one of the o-rings had failed. Below is what the final drive on the rear wheel...

www.nt-owners.org

ST1100Y · Nov 13, 2020

rc_heli_nut said:
Recent thread on this:

That isn't about the side gear I'm referring to...
(hub dampers, drive spline, final drive have been checked and are OK on my GF's NT...)

By the location of the noise I suspect on the following:
- U-joint (easy)
- damper (loc 9 & 10)
- gear shimming off (loc 5 & 7)

Woodaddict · Nov 13, 2020

you can check U joint by moving rubber boot behind foot peg. its a pain to get back on seated in the groove, but easier than swing arm. no need to take off swing arm. if you were to take off final drive again, then long shaft comes out the swingarm, the U joint will fall off in boot, push that aside or take off, to take off joint to look at it. mine lasted till 188,000 miles. the NT noise IS very noisy, your just wasting your time looking at the countershaft. that runs on the oil inside

so to save you time, pretty sure everything is ok unless you have over 150,000 miles on it. its just a noisy drivetrain

ST1100Y · Nov 13, 2020

Woodaddict said:
you can check U joint by moving rubber boot behind foot peg. its a pain to get back on seated in the groove, but easier than swing arm. no need to take off swing arm. if you were to take off final drive again, then long shaft comes out the swingarm, the U joint will fall off in boot, push that aside or take off, to take off joint to look at it.

Been there, looked all fine to me... :unsure:

the NT noise IS very noisy, your just wasting your time looking at the countershaft.

Seems I'm spoiled from the years of (japan build) ST1100 then

There is no slack, no clunk, the throttle bound to the contact patch of the rear tire :sneaky:

rc_heli_nut · Nov 13, 2020

Now I see your question.

The damper assembly, by design, has some slack. My NT will make the same noises you're mentioning, in gear on the center stand. Without the road load on the tire it's normal, all the driveline tolerances are free to clang back and forth. I wouldn't worry about it, operating as designed.

Brad

ST1100Y · Nov 14, 2020

rc_heli_nut said:
My NT will make the same noises you're mentioning, in gear on the center stand. Without the road load on the tire it's normal, all the driveline tolerances are free to clang back and forth.

Sure, the slack adds by the sum of moving parts... (even on front wheel driven cars occasionally one can sense the slack in the differential...)
Sensing slack on an ST1100 is indication for "something is worn" though :sneaky:

I'll check/compare with my friend's NT700VA, which has only 10,000km on the clock (so basically new)...

cheers!

DirtFlier · Nov 14, 2020

The clunk-clunk from the rear wheel with the bike on the centerstand is normal. I bought my NT new and it now has 75k miles under its belt and that clunk-clunk was there from the beginning. Also, u-joint problems with Hondas are pretty rare.

Stop worrying and just ride it!

ST1100Y · Nov 14, 2020

DirtFlier said:
Stop worrying and just ride it!

The issue is that my GF is riding it, so don't want her to have any trouble with it (which would likely "get me into trouble"...

)

seagrass · Nov 14, 2020

Yes I also agree the noise is normal.

Sometimes it can sound like a tin of marbles being shaken.

Seagrass

Phil Tarman · Nov 14, 2020

ST1100Y said:
The issue is that my GF is riding it, so don't want her to have any trouble with it (which would likely "get me into trouble"... )

She's not likely to have any trouble with it. You change the tires, I believe, and as long as you lube the splines and replace the O-rings when you put it all back together, she'll be fine.

ST1100Y · Nov 14, 2020

Phil Tarman said:
... as long as you lube the splines and replace the O-rings when you put it all back together...

Yeah... we bought it used, I dragged it into my shed/workshop right away where I had to find this

(mind that the dealer installed a new rear tire prior pick-up...)

All cleaned, new hub dampers, new aluminum bushings, new O-rings, Gn-Plus where it belongs... all set now...

DirtFlier · Nov 15, 2020

Those parts shown in the photos DO NOT get the Moly 60 grease and the fact that they weren't cleaned is not unusual nor harmful. The Moly 60 is only applied to the drive & driven splines.

People who are working in a shop have no real need to make everything spotless and most likely they're working on "flat rate," where most tasks are assigned a certain number of minutes to complete. Flat Rate is used primarily for factory reimbursement on warranty work but dealers can also use it to provide a time estimate for normal maintenance work.

ST1100Y · Nov 15, 2020

DirtFlier said:
Those parts shown in the photos DO NOT get the Moly 60 grease....

:sneaky:

People who are working in a shop have no real need to make everything spotless...

Neither the missing/broken O-ring, nor the worn dampers/bushings (or the total lack of lubricant) were mentioned by the dealer...
They just silently send you back on the road, with expensive aftermath prone to happen...

My bike, my safety, my money...
Dry and unattended the movement of the spline assy against the wheel will wear down the bearing boss...
not only the drive spline assy and the ring-gear are at at risk, you'll also need to buy a new rear wheel...

Over the years have episodes like this driven me to do all my bike service and overhauls myself... :cautious:

rc_heli_nut · Nov 15, 2020

I agree. After having to replace the final drive and flange due to missing thrust washer, I do all the work on the NT myself. If my plans involve a rear wheel remove/install, I'll devote an entire day to the project so I can check and inspect everything.

Brad