800GS shock bolt design flaw?

[Gangplank]

I'm going to ride mine as is for now. If and when I do any sort of shock change/spring change to the rear (doubtful but who knows)... I'll come back here nad read this 45 pages of this and that, that and because you said, did this, that's the problem. Maybe by then someone will know what they are talking about.

For now, if'n it aint broke I'm not messing with it.

[Chop Chop]

Was talking to my dealer about another issue, and just happened to mention whether they had any shock bolts in stock. They did as they had to order some in as another customer had bent one. First time I've heard it happening here. Will try to get more info when next at the dealership.

I wonder if it was incorrect torque values from factory. Mine was approx 80Nm when I checked it.

[Tom Myers]

After 45 pages there is so much commentary I can understand if heads are spinning.

If you want to maintain your F800GS properly, this shock bolt should be checked, and restored to proper torque before the next suspension bottom-out. Anyone who rides off-road should do this soon.

For the original BMW shock, the easiest way to make sure your bike is up to BMW design standards, is to simply add a greased washer under the bolt head then re-torque the bolt . I'd put some light oil (like WD40?) on the bolt threads but lube the washer with motor oil or grease then re-torque the bolt to 100Nm with a torque wrench. This is simple, and probably all you will ever need to do.

If you come to our store in Seattle we can help you to do this yourself. It only takes a few minutes and you're ready to go.

Tom (TOURATECH-USA)

[nachtflug]

Originally Posted by Tom Myers

After 45 pages there is so much commentary I can understand if heads are spinning.

high priced low quality product does tend to get peoples heads spinning but you can always count on touratech to offer and even higher priced resolutions for lifes little setbacks.

[Wheedle]

Originally Posted by nachtflug

high priced low quality product does tend to get peoples heads spinning but you can always count on touratech to offer and even higher priced resolutions for lifes little setbacks.

Someone hasnt been drinking his Bavarian Kool-aid....

[Lion BR]

Originally Posted by nachtflug

high priced low quality product does tend to get peoples heads spinning but you can always count on touratech to offer and even higher priced resolutions for lifes little setbacks.

Did I get this straight?

TT resolution for this case:
Advise/recommendation/analysis/and offer for doing the job: free.
Washer: US$0.2


If you do it yourself, add:
Dab of WD-40: US$0.05 (approximately, YMMV)
Use of torque wrench: $0.0 (if you have to borrow a friend's torque wrench, it may cost you a lot more in beer)

For both scenarios:
Nachtflug comment: Priceless.

Man, that is a high priced resolution to the "problem".

So it is not like Nachtflug has skipped the kool-aid drink. It is what else has him been drinking. (Now, remember, he is probably suffering from some form of modified cabin fever, snowed in and all, so please give him a discount while evaluating his assertions).

Lion

[The Griz]

Installed a new upper shock bolt with 12mm hardened steel washer. The washer is thicker than 1mm. It's about 2-3mm thick. I like that. Torqued to 100 Nm with washer and no thread locker as the service manual says no thread locker on upper bolt. Greased the washer with Bel-Ray waterproof grease as well.




12mm hardened steel washer, 2-3mm thick.



Installed. I'm done with the shock bolt thing!....... hopefully, knock on wood.

[YetiGS]

Originally Posted by The Griz

Installed a new upper shock bolt with 12mm hardened steel washer. The washer is thicker than 1mm. It's about 2-3mm thick. I like that. Torqued to 100 Nm with washer and no thread locker as the service manual says no thread locker on upper bolt. Greased the washer with Bel-Ray waterproof grease as well.

12mm hardened steel washer, 2-3mm thick.

Installed. I'm done with the shock bolt thing!....... hopefully, knock on wood.

My bolts came last Friday while I was on vacation so I got them today. Will install this weekend and also be DONE!!

[kmueller_gs12]

@Tom Myers

sorry tom you are wrong.
please read again my post, i don´t add a washer.
i only take a wrench and hold the bench nut while torque the bold up to 100nm.

regards klaus

[The Griz]

Originally Posted by kmueller_gs12

@Tom Myers

sorry tom you are wrong.
please read again my post, i don´t add a washer.
i only take a wrench and hold the bench nut while torque the bold up to 100nm.

regards klaus

If you don't use a washer you run the risk of running out of threads on the bolt as it threads into the bench nut. As some one said prior, if you run out of threads and bottom out in the bench nut your torque wrench will read 100Nm, but the bolt will not have proper tension. Tom @ TT is correct in recommending the washer. I recommend it as well as others that have posted on this thread.

[The Griz]

One other thing. Before installing, I compared the length of my new unused bolt to the length of the two other ones that I've used prior. They were exactly the same length as the new unused one. I used a caliper. Therefore, my conclusion is that these bolts don''t "stretch", and are reuasble. This also makes sense as to why BMW doesn't spec it do be replaced. The only reason you'd need to replace it I guess would be due to bending. Now the bottom one on the other hand: always replace due to the microencapsulation. Hopefully it's not illegal to post a snippet of the manual. Admins, sorry if it is! Please remove if necessary!

[Chop Chop]

Originally Posted by The Griz

If you don't use a washer you run the risk of running out of threads on the bolt as it threads into the bench nut. As some one said prior, if you run out of threads and bottom out in the bench nut your torque wrench will read 100Nm, but the bolt will not have proper tension. Tom @ TT is correct in recommending the washer. I recommend it as well as others that have posted on this thread.

The only reason I'm using a washer is to reduce the friction on the bolt head during torquing of the bolt. Washer is lightly greased. As from my measurements I'm doubtful I will run out of threads on the bolt.

[Chop Chop]

Originally Posted by The Griz

One other thing. Before installing, I compared the length of my new unused bolt to the length of the two other ones that I've used prior. They were exactly the same length as the new unused one. I used a caliper. Therefore, my conclusion is that these bolts don''t "stretch", and are reuasble. This also makes sense as to why BMW doesn't spec it do be replaced. The only reason you'd need to replace it I guess would be due to bending. Now the bottom one on the other hand: always replace due to the microencapsulation. Hopefully it's not illegal to post a snippet of the manual. Admins, sorry if it is! Please remove if necessary!

Hi Griz,

IMU a 100Nm is not enough to stretch a class 10.9 bolt beyond reusing. In regards to the bolt bending, if the frame/associated parts have not failed then the bolt has stretched to get the bend. Academic I know as bolt would obviously be discarded either way. Perhaps I'm misreading the logic applied (known to happen).

When I reused the upper bolt, I used degreaser to clean the threads to help minimize the friction for torquing. I also cleaned the lower bolt and used a threadlocker and greased under the bolt head.

[The Griz]

Originally Posted by OffAgain

The only reason I'm using a washer is to reduce the friction on the bolt head during torquing of the bolt. Washer is lightly greased. As from my measurements I'm doubtful I will run out of threads on the bolt.

As johngil convinced me, the washer is cheap insurance on not bottoming out the threads. Even if you don't think it's possible, why not use one anyway to assure it?


....I'd also make dang sure you use at least permatex red threadlocker on that bottom bolt. The microencapsulated thread locker that comes on the bolt from the factory is designed to hold much stronger than even the red "over-the-counter" stuff us consumers can get at the hardware store..... remember how hard it was to remove that bottom bolt in the first place? For me personally, even with a breaker bar it was hard as hell! Much harder than any red store-bought thread locker I've had to break loose in the past!

[YetiGS]

Just replaced my bolts and added the washer to the top bolt. Lubed the faces on both.


Pleased to say the original shock bolt is still straight.