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Discussion Starter #1
I purchase a 1997 916 at the beginning of the season and have been steadily working through some issues (as to be expected). The issue that has persisted: Off power with the clutch lever engaged or the bike in neutral (ie click it in to neutral while rolling up to a stop) there is a thunking from the back of the bike. It's not something I notice a lot because it only happens the few feet you roll with the clutch engaged or in neutral right before you come to a stop.

Initially I had discovered that the rear wheel was actually loose. The previous owner had not installed the retaining clip correctly and the rear wheel could wobble on the axle. Decided that it would be worth inspecting the wheel bearings as they could have been damaged by this at which point I discovered the eccentric holder was upside down. The bearings were okay. I replaced the chain and sprockets and reset the chain tension with the 1" of slack and the eccentric rotated correctly toward the 5-6 o-clock position. I then re-installed the rear wheel, torqued it to the immense factory spec and installed new clips on both sides.

The problem persists although greatly diminished. The loose wheel had made the bike feel bizarre everywhere, which I had previously attributed to some other problems with the suspension that I have since sorted. The odd feeling is gone, but there is a less pronounced thunking that still happens. I thought I had fixed the problem but today I noticed it again. Here are my thoughts:

Could it be too much chain slack? I had not been able to replicate the effect immediately after the aforementioned service I performed. I'm wondering if the RK gold X-ring chain has broken in a bit and I'm feeling the chain sort of slap against the chain sliders.

Could it be the rear rotor having a massive amount of run out and thunking on the pads? I don't use the rear brakes ever so they don't get much attention.

Could it be a wheel or tire issue?
 

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Old Wizard
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Check the rear wheel again.

If the nut is under-torqued it will allow the nut to loosen, allowing the wheel to rotate in its mount and be damaged by repeated acceleration/braking impact loads that will ovalize the four locating pins holes on the backside of the wheel. The permanent fix is to have a machine shop drill-out the oval holes and then press-in some cylindrical inserts that have the correct inside diameter to match the drive pins.

Note that the wheels on some Ducati models have four slots and four holes on the backside. If the pins are incorrectly installed in the slots instead of the holes, the shoulder of the pins prevent the wheel from being snugged-up fully. The wheel will then loosen as the pin shoulder wears into the seat. The first time it mistakenly happens you have to force the pins into the slots, but after that they’ll go in fairly easily.
 

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Discussion Starter #3
Check the rear wheel again.

If the nut is under-torqued it will allow the nut to loosen, allowing the wheel to rotate in its mount and be damaged by repeated acceleration/braking impact loads that will ovalize the four locating pins holes on the backside of the wheel. The permanent fix is to have a machine shop drill-out the oval holes and then press-in some cylindrical inserts that have the correct inside diameter to match the drive pins.

Note that the wheels on some Ducati models have four slots and four holes on the backside. If the pins are incorrectly installed in the slots instead of the holes, the shoulder of the pins prevent the wheel from being snugged-up fully. The wheel will then loosen as the pin shoulder wears into the seat. The first time it mistakenly happens you have to force the pins into the slots, but after that they’ll go in fairly easily.

I'll try to get the bike up on the stand this afternoon and check that. Thanks for the input!

-Ed
 

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Discussion Starter #4
My drive pins are sheared and the holes on my wheels are badly ovalized. Does anyone know the part numbers for the pins on the 916 and the screws for them? I can only find the part numbers for the hypermotard pins online when I google. I'm not sure (and doubt) if they are the same.

I'll try to get the bike up on the stand this afternoon and check that. Thanks for the input!

-Ed
 

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My drive pins are sheared and the holes on my wheels are badly ovalized. Does anyone know the part numbers for the pins on the 916 and the screws for them? I can only find the part numbers for the hypermotard pins online when I google. I'm not sure (and doubt) if they are the same.
This happened to my bike when it was a few weeks old - wheel had not been correctly torqued by the dealer and I hadn't checked it or even got a suitably sized socket at that time.

Mine needed a new hub (and wheel) as the pins had also worn their fitting holes in the hub oval - worth checking this.

I would think Hypermotard/848/Monster etc pins are probably the same.

As an aside my (aftermarket) Marchesini wheel has 2 sets of location holes giving another 'chance' should it happen again.
 
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