TVS 961 RECALL....

People are forgetting that this was an issue on the Sportster and other HD 1990s models, which the 961 gearbox is modeled after. The fix was to drill out the rivets and install new gear with 5/16 bolts. Nobody learned from the HD mistakes since the beginning of the "new" Norton. Dreer used Baker gears, so I would assume he used HD Ring gear which was then copied by Garner , etc
 
Can I please check, clearly some people have been contacted to say their bikes ARE impacted, has anyone been given the all clear yet?
 
DP1000 said:
Can I please check, clearly some people have been contacted to say their bikes ARE impacted, has anyone been given the all clear yet?
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Give Norton customer service a call, they are very helpful and will get back to you. They did say, if I hadn't called DVLA will contact those affected and of course themselves.
 
Heard nothing yet, so just emailed the dealer to ask what's happening. I did see on PH that some owners have already been contacted and got a date for their bikes to be collected..
 
Just contacted Norton and they will be collecting my bike in the next few days , it will be taken back to TVS and repaired at the factory not the dealers.
 
Fast Eddie said:
When I first looked at the diagram posted by Blighty, I though that ‘loose’ and ‘broken’ were two separate failure modes.

But thinking on, I’m inclined to think that the shouldered bolts are plenty strong when fully tightened to the shoulder. In that case, the sheer load is not fully acting on the small thread.

But if they become loose, even a smidgen, then the sheer load does fully act on the thread.

So I’m now thinking that sheered bolts is more likely to be a symptom of loose bolts, rather than a separate failure mode.

And that therefore, fully tightened and loctited bolts should be perfectly fine.

But… these are only the meandering thoughts of a layman…
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Two dowel pins, captured by blind holes in each piece, and conventional securing hardware would have worked so much better. Easier to produce. (Cheaper)

This is a poor application for industrial type shoulder bolts.

Someone left the children unattended near the design software again.
 
concours said:
Two dowel pins, captured by blind holes in each piece, and conventional securing hardware would have worked so much better. Easier to produce. (Cheaper)

This is a poor application for industrial type shoulder bolts.

Someone left the children unattended near the design software again.
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Not true. Shoulder bolts are highly specified for shear loads.
 
concours said:
Two dowel pins, captured by blind holes in each piece, and conventional securing hardware would have worked so much better. Easier to produce. (Cheaper)

This is a poor application for industrial type shoulder bolts.

Someone left the children unattended near the design software again.
Click to expand...
Really useful posts - NOT! From someone judging by their signatures rides antiques.
 
Bevelheadmhr said:
Heard nothing yet, so just emailed the dealer to ask what's happening. I did see on PH that some owners have already been contacted and got a date for their bikes to be collected..
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It is out of the dealers hands (I called mine initially). Just call Norton and they will organise the rectification work ASAP.
 
concours said:
Two dowel pins, captured by blind holes in each piece, and conventional securing hardware would have worked so much better. Easier to produce. (Cheaper)

This is a poor application for industrial type shoulder bolts.

Someone left the children unattended near the design software again.
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Reckon they let the old folks home near it too……
 
concours said:
So you say.
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You always have to troll here, don't you? And it's not just me who says so. Or do you need to see my mechanical engineering degree as well as my CV? But actually, your comment shows a fundamental misunderstanding of fastener design and mechanical engineering. Shoulder bolts are specifically engineered for high shear applications. Their unthreaded shoulder offers a larger load-bearing surface and prevents the concentration of stress at the threads, which is precisely why they’re used in aerospace, tooling, linkages, and pivot joints where shear loads are dominant.

Unlike a shear pin, which is designed to fail under a certain load, a shoulder bolt is designed to resist shear, provide alignment, and allow reusability. This isn’t opinion—it’s basic mechanical engineering, backed by sources. If you're going to argue this, you'll need more than internet guesses. Try doing some actual reading first.

Since you have some free time, you can look up shoulder bolts and shear applications. You could also look at lectures from MIT, papers from NASA, or every helicopter manufacturer that uses them for shear applications. Seems like they might know a thing or two

The ring gear is a sacrificial part, and by using shoulder bolts, repairs can be made(CHEAPER) than replacing the whole basket.
 
City Garage said:
You always have to troll here, don't you? And it's not just me who says so. Or do you need to see my mechanical engineering degree as well as my CV? But actually, your comment shows a fundamental misunderstanding of fastener design and mechanical engineering. Shoulder bolts are specifically engineered for high shear applications. Their unthreaded shoulder offers a larger load-bearing surface and prevents the concentration of stress at the threads, which is precisely why they’re used in aerospace, tooling, linkages, and pivot joints where shear loads are dominant.

Unlike a shear pin, which is designed to fail under a certain load, a shoulder bolt is designed to resist shear, provide alignment, and allow reusability. This isn’t opinion—it’s basic mechanical engineering, backed by sources. If you're going to argue this, you'll need more than internet guesses. Try doing some actual reading first.

Since you have some free time, you can look up shoulder bolts and shear applications. You could also look at lectures from MIT, papers from NASA, or every helicopter manufacturer that uses them for shear applications. Seems like they might know a thing or two

The ring gear is a sacrificial part, and by using shoulder bolts, repairs can be made(CHEAPER) than replacing the whole basket.
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Lol, I wrote DOWEL PIN, but clearly you think it's the same as a shear pin.💡
Certainly my 50 years of millwright work pales in comparison to your vast knowledge. 📖


Defensive much?
Troll?

I explained a SIMPLE, EFFECTIVE cure to solve the problem, and make certain it doesn't re-occur.

You can crap all over as you see fit, but someone with skills will find it useful. 💡😎
 
In the tool and die industry, we use both shoulder bolts and dowel pins.
Both would work on the clutch set up. Anything can and will fail when used or applied improperly.
Clearly, Norton failed to properly perform the assembly and they’re fixing the issue as well. I’m just not sure they should overlook the bikes they assume are ok. Why not check them all? It’s not like they made thousands of 961 bikes.
 
NorTriDuc said:
I’m just not sure they should overlook the bikes they assume are ok. Why not check them all? It’s not like they made thousands of 961 bikes.
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If the issue is ‘contained’ within certain numbers, it means they can be confident that the others followed the standard process, and if the standard process provides a standard ‘accepted’ outcome, then there is simply no need.
 
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