Final Drive-Driveshaft Clunk

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Final Drive-Driveshaft Clunk

Post by MiddleAgedMissile » Wed Oct 21, 2020 8:40 pm

This is not the first post I wanted to make on this forum, but here goes.
Picked up a 2015 Gear-Up today and rode it about 120 miles to my cabin where I have a shop and can keep it dry This is my first sidecar rig and Urals are new to me. The last leg of the ride is gravel and the last mile or so I took off my helmet and ear plugs and noticed a slight thumping with each rotation of rear wheel or driveshaft. No noise when clutch engaged. Immediatly starts clanging when engaged. By the time I arrived, the last mile or so the noise was loud, a hard clank with rotation of the wheel. I parked and looked the bike over and then noticed that I may have had the 2wd engaged. So...what the hell Have I done on my first damn ride? The shaft from rear wheel to sidecar wheel turns whether lever is forward or back. There seems to be a good bit of play at point where sidecar shaft attaches to rear wheel.
Last edited by MiddleAgedMissile on Wed Oct 21, 2020 10:51 pm, edited 1 time in total.
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Re: Final Drive-Driveshaft Clunk

Post by stagewex » Wed Oct 21, 2020 9:09 pm

Congrats on your Patrol.
So was it engaged (2WD) or not? It happens. The shaft is going to turn anyway. I just wouldn't think 120 miles in 2WD is going to wreak something. If it was in 2WD and isn't now... is it quieter?


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Re: Final Drive-Driveshaft Clunk

Post by MiddleAgedMissile » Wed Oct 21, 2020 9:16 pm

I rode it afterwards with 2wd engaged and not, same loud clunk at each rotation. I plan to take a closer look tomorrow in the daylight. Had a great time on the rig today. The fall colors are popping in NW Arkansas and SW Missouri.
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Re: Final Drive-Driveshaft Clunk

Post by Lokiboy » Wed Oct 21, 2020 9:21 pm

Don’t think you were in 2WD. RATIONALE. you wouldn’t have been able to steer on hard pavement. Don’t over think it. The rig will make lots of uneasy clucks. Vast majority of the time it’s a one off event. As Stagwex said, the axle turns regardless of being in 1WD vs. 2WD.

As for the noise, it’s possible something came loose inside the FD. So hard to tell. If you’re worried, drain the FD and see if you have large chunks of metal. If not, lift the side car and spin the wheel to have peace of mind that you’re not in 2WD.

Ride it. If the noise persists, video it, if possible, to help the collective with possible causes and fixes.

Congrats on getting the the rig.
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Re: Final Drive-Driveshaft Clunk

Post by MiddleAgedMissile » Wed Oct 21, 2020 9:31 pm

Thanks,
Looking at the manual I was not in 2wd. I will try some of the things you mentioned tomorrow. I do my own wrenching but the bike is new to me.
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Re: Final Drive-Driveshaft Clunk

Post by chaos2 » Thu Oct 22, 2020 12:01 am

the shaft turns whether the 2wd is engaged or not, that's normal. Clunking could be from a bad U joint, it would be pretty obvious if one is loose.
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Re: Final Drive-Driveshaft Clunk

Post by treebone » Thu Oct 22, 2020 12:37 am

First thing I'd check is the donut, as well as the u-joints.
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Re: Final Drive-Driveshaft Clunk

Post by CrankyTom » Thu Oct 22, 2020 6:35 am

I've had an occasional SLIGHT clunk on my 2012 if the sidecar wheel bearings need adjusting.
Easy to check,just grab the top of the sidecar wheel and give it a pull laterally,there should not be a lot of play.
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Re: Final Drive-Driveshaft Clunk

Post by Lokiboy » Thu Oct 22, 2020 6:51 am

CrankyTom wrote:
Thu Oct 22, 2020 6:35 am
I've had an occasional SLIGHT clunk on my 2012 if the sidecar wheel bearings need adjusting.
Easy to check,just grab the top of the sidecar wheel and give it a pull laterally,there should not be a lot of play.
Where is it and how do you adjust it?
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Re: Final Drive-Driveshaft Clunk

Post by Lokiboy » Thu Oct 22, 2020 6:57 am

Good point about the U-joint. Also, make sure you grease them (x3) about every 5,000kms. You’ll be amazed how much you have to add each time.

Thinking about the “clunk”. Lift the pusher and side car wheel. By hand, rotate the pusher and see if the clunk is repeatable and occurs when the tire is at the same place. Even if it doesn’t, you can better determine where it’s coming from.
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Re: Final Drive-Driveshaft Clunk

Post by MiddleAgedMissile » Thu Oct 22, 2020 12:27 pm

ImageJacked her up and found a final drive cover bolt missing and the other bolt loose. I tightened the existing bolt and replaced the other, hoping I had found a simple fix. Sadly no, when I placed the bike in gear and lightly applied rear brake to put a load on the drive it banged really loud with a pronounced shudder with each rotation. Looks like she is going under the knife. Couldn’t be more disappointed. Attempting to attach a video next.

87E9F62C-89ED-475C-B6A9-5CF705CA9B9C.jpeg
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Re: Final Drive-Driveshaft Clunk

Post by MiddleAgedMissile » Thu Oct 22, 2020 12:57 pm

Video of the terrible noise...
Jacked her up and placed in first gear with a light touch of rear brake.
[youtube] https://youtu.be/4mIQeq5cDcc[/youtube]
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Re: Final Drive-Driveshaft Clunk

Post by Burt1713 » Thu Oct 22, 2020 1:01 pm

When you had the bike jacked up was the sidecar wheel still on the ground and not rotating? You might try rotating the rear wheel by hand to see if you can feel any binding, etc. Putting the bike in gear, with the engine off, And try rocking the rear wheel to see if there is excessive play in the driveline.
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Re: Final Drive-Driveshaft Clunk

Post by MiddleAgedMissile » Thu Oct 22, 2020 1:11 pm

Both rear wheel and sidecar wheel were off the ground.
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Re: Final Drive-Driveshaft Clunk

Post by Msblu79 » Thu Oct 22, 2020 2:28 pm

What is the condition of the flex coupling (donut) at the output of the tranny. Look carefully at the rubber part and see if it is torn out and the shafts are hitting each other, if they did hit and are damaged they will have to be replaced along with the donut or your new coupling life will be very short.
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