800GS shock bolt design flaw?

[DockingPilot]

Originally Posted by Indy Unlimited

Yes I think we can run a single 21mm 0.D. x 12mm I.D. x 70 mm long custom bronze oilite bushing! It just happens that the rubber bushing is on a stock 21 mm diameter steel spacer and the Hyperpro shock has an eye bearing with a 21mm O.D. so it looks like we a potential solution for the Hyperpro shock.

And of course you have me on the very top of the list eh ?

Let tell you guys what kind of guy Indy is. We both had or have, TE610's and were on the 610 board. Other than that he didnt know me from adam. I needed to buy a flywheel puller. He spotted my post and pm'd me saying he'll fed-ex me his to use, then just send it back. He did just that. That's the kinda guy he is. I still owe ya brother.
Now, let me tell what kinda fella I am. I kept the flippin thing and screwed him.
No, I didn't........

[Indy Unlimited]

Good one Frank thanks for the character reference! I still love my TE610 but it really has a tough time with adventure loads. You will get a bushing shipped to you as soon as I get the prototype installed and working correctly.

I have a supplier that made me a batch of small custom bushings for the famous clutch bell wear issue on the Husky TE610. I will call him on Monday and see what a run of custom bushings will run per bushing for a group buy.
Does anyone know if the spherical bearing on the Ohlins shock is also 26mm O.D. as well. Then we can get the same solution for Hyperpro and Ohlins.

[tmex]

Originally Posted by DockingPilot

Now thats really interesting stuff.

Tmex, you have the oem shock in ?

Yes DP. My upper bolt was slightly bent with the stock shock. I am switching to the Hyperpro progressive shock spring (still stock shock) next install along with 12.9 McMaster bolts. I rode the Yellow Bitch pretty hard, but I do not recall bottoming the suspension, but in the heat of battle who knows? I think if the shock bottoms there is no place for the energy to go except into bending the bolt. Not sure the bushing thing is on the right track based on my bending with the stocker. BTW, I had the prelaod cranked up pretty high. It will be interesting to see if the Hyperpro spring and better bolt are the answer. I'll put 1000 miles on it and tear it down.

[Indy Unlimited]

Take it easy on that ankle TMEX. No rough riding for a while.

[YetiGS]

Originally Posted by Indy Unlimited

Take it easy on that ankle TMEX. No rough riding for a while.

Good point. Maybe he should send that spring and bolt down to me and I'll test my shock bolt. I weigh a fair bit more than tmex too, so it'll be a better test.

[cisco]

Originally Posted by tmex

Yes DP. My upper bolt was slightly bent with the stock shock. I am switching to the Hyperpro progressive shock spring (still stock shock) next install along with 12.9 McMaster bolts. I rode the Yellow Bitch pretty hard, but I do not recall bottoming the suspension, but in the heat of battle who knows? I think if the shock bottoms there is no place for the energy to go except into bending the bolt. Not sure the bushing thing is on the right track based on my bending with the stocker. BTW, I had the prelaod cranked up pretty high. It will be interesting to see if the Hyperpro spring and better bolt are the answer. I'll put 1000 miles on it and tear it down.

Now you guys are scaren' me! Might as well pull the shock bolt while I'm waiting for my seat.
Cisco

[RedHawk47]

The 16mm shoulder bolt is an excellent idea. It has considerably greater bend strength. There are several factors to consider before making the change. I haven't taken my bike apart to measure things so I need your input.

1. How much material is there around the holes in the frame tabs/mounts? If you drill the hole larger is there risk of failure at the holes?
2. I believe it was stated that the bushing in the OEM shock had enough material that you could drill it out to 16mm. Even if the wall thickness was only 1mm after drilling that would be enough.
3. The bushing/sleeve to the right of the shock has to be there. What is it's OD? If you drill it out to 16mm it's wall thickness should be at least 2mm.
4. Check the length of the shoulder (90mm) versus the length of the bushing stack. Add washers - I suggest plain or hard - so that you clamp the bushing stack solid.

For the Olin and Hyperpro shocks I recommend a custom bushing set, particularly if you are using the 12mm bolt:
A sleeve that is the length of the two provided bushings, ID of 12mm or 16mm, depending on the bolt used, and OD the same as the small OD on the supplied bushings.
Plus, two rings, ID equal to small OD, OD equal to large OD, and thickness equal to the width of the shoulder on the supplied bushing.
This bushing will reduce the chance of bending a 12mm bolt, but if you have bent the bolt when using the OEM shock all bets are off.

[Indy Unlimited]

Once you take it apart you will notice that the stock shock has a rigid bushing that is 21mm O.D. and 40 mm long. The spacer with the rubber bushing is 21mm O.D. and 30 mm long. The issue is it should be a continous 70 mm long bushing to support the 12 mm bolt over that span without a bending load in the middle. The frame has plenty of metal and if we went bigger it requires only drilling a larger hole on the outside frame plate where the head of the bolt goes up against it.
That is why I feel we need a larger 16 mm bolt or one full length single bushing to take the bending load off of the bolt. The female nut side is 20 mm O.D. at the threads and one could machine it for a 16 mm shoulder bolt to seat up to the threads which dont start until you are 1/2" deep inside the hole.

Right now I am leaning to a 2 bushing design. a single steel bushing 70 mm long either 21 or 22 mm O.D. / 12mm I.D. and a 40 mm single 26mm O.D. / 21 or 22mm I.D. oil impregnated bronze bushing. This will give us the spanning strength for the bolt and a replaceable bearing for wear. There is a standard oilite bearing with a 26 mm O.D. and 22 mm. I.D x 20 mm long and for the sake of easy replacement we could put 2 of those over the custom steel bushing as well. That is why we may want 22 mm O.D on the steel bushing for the Ohlins and Hyperpro.

Any better ideas would be appreciated. I am still reviewing the best design concept over the next few days before moving forward.

[tmex]

Originally Posted by Indy Unlimited

Take it easy on that ankle TMEX. No rough riding for a while.

The worst part is having to take a cage to work. About five hours of extra commute time a week tossed right in the toilet relative to a bike.

BTW, changing the spring require a spring compressor. Springs always scare me.

[cisco]

Originally Posted by tmex

The worst part is having to take a cage to work. About five hours of extra commute time a week tossed right in the toilet relative to a bike.

BTW, changing the spring require a spring compressor. Springs always scare me.

Just think how much better it will feel........... when it quits hurting.
Cisco

[DockingPilot]

Ankles are highly over rated T., I say chop it off and move on.

[YetiGS]

Originally Posted by DockingPilot

Ankles are highly over rated T., I say chop it off and move on.

There's a dude around here who rides a plated CRF450X supermoto. He's got a prosthetic lower right leg. Seems to ride just fine.

I'm with DP on this one.

[tmex]

Stock shock - stock bolt ~7000 miles. Bolt is backlit in the jaws of the drill press vise. It is hard to capture a small bend photographically. It is actually pretty obvious to the eye when you have the bolt in your hand.



I am going to keep my ankle. I have become attached to it over the years.

[never.ride]

That's exactly what my bent bolts looked like, both the stock one and the higher grade one.

Oh, and I'm 150 lbs with all my gear....

[LaPorte]

I get my 2010 f 800 GS next week, so I was thinking. I'll put the new bike on my old bike trailer and just tow it where ever I want to go adventure riding. That way the forks woun't feel harsh, the rear wheel bearings woun't disintegrate, the shock bolt woun't bend, chain woun't snap. Woun't need knobb tires and the gearing is perfect. Woun't need gas so it woun't splash all over. Let's see did I miss anything. Then when I sell the bike, the phrase "like new" will really mean something.

LaPorte