Lucky catch- snapped penske 8983 rear shock

[sylvester]

Hi all,

I got a Penske 8983 rear shock about two years ago, Custom built for 2007 fjr and found it a massive improvement from factory shock. I do get the bearings done\greased every six months and my mechanic "lightly" tapped the bolt out of bottom of shock and bottom snapped in two. Looks like a faulty part to me seems to be close to the join of the threaded part. Or Maybe not designed for bumby Irish roads? In Morning I am going to go to Local DHL shipping company in morning in Galway , Ireland and ship it to penske distributor, usa.

Lucky it was caught during routine service

pics here

https://s266.photobucket.com/albums/ii271/Biker_ieHornet224/?action=view&current=luckycatch-shocksnapsduringservice005.mp4

https://s266.photobucket.com/albums/ii271/Biker_ieHornet224/?action=view&current=luckycatch-shocksnapsduringservice003.mp4

https://s266.photobucket.com/albums/ii271/Biker_ieHornet224/?action=view&current=brokenshock030.jpg

https://s266.photobucket.com/albums/ii271/Biker_ieHornet224/?action=view&current=brokenshock030.jpg#!oZZ11QQcurrentZZhttp%3A%2F%2Fs266.photobucket.com%2Falbums%2Fii271%2FBiker_ieHornet224%2F%3Faction%3Dview%26current%3Dbrokenshock029.jpg

https://s266.photobucket.com/albums/ii271/Biker_ieHornet224/?action=view&current=brokenshock030.jpg#!oZZ9QQcurrentZZhttp%3A%2F%2Fs266.photobucket.com%2Falbums%2Fii271%2FBiker_ieHornet224%2F%3Faction%3Dview%26current%3Dbrokenshock031.jpg

https://s266.photobucket.com/albums/ii271/Biker_ieHornet224/?action=view&current=brokenshock030.jpg#!oZZ8QQcurrentZZhttp%3A%2F%2Fs266.photobucket.com%2Falbums%2Fii271%2FBiker_ieHornet224%2F%3Faction%3Dview%26current%3Dbrokenshock032.jpg

https://s266.photobucket.com/albums/ii271/Biker_ieHornet224/?action=view&current=brokenshock030.jpg#!oZZ7QQcurrentZZhttp%3A%2F%2Fs266.photobucket.com%2Falbums%2Fii271%2FBiker_ieHornet224%2F%3Faction%3Dview%26current%3Dbrokenshock035.jpg

 

[escapefjrtist]

Haven't seen a Penske do that on this side of the pond. Interested to see what Penske has to say about it.

Possibly overtightened the bottom yoke bolt resulting in a fatigue failure?

Here's two of your pics...

--G

 

[DJB]

Not having the part here for testig it does look like a material issue. I bet who ever heat treated it did something wrong.

 

[Fred W]

My guess is that the wrong bolt was used to hold this (the lower end of the shock) to the relay arm. The correct bolt (#28 below) has a shoulder that fits inside the larger diameter hole in the shock bracket and butts into the inside race of the relay arm bearing (#29). When the assembly is tightened up the side of the bracket with the smaller hole is sandwiched between the opposite side of #29 and the nut and washer (30, 31), which restrains the lower shock end laterally, but the large diameter end is not clamped and there should be no lateral (squeezing) force applied to this bracket.

OTOH if someone used a bolt with no shoulder then the tightening force of the bolt would be applied squeezing the bracket in a way it was not designed for.

Picture of the assembly from the parts breakdown:

 

[sylvester]

Hi Fred w

Correct bolt was used and it had metal sleeve on bolt that went between shock bracket. Part will be with traxxion this week.

 

[smellthat?]

Aftermarket shocks tend to supply their own bolts for this location - you don't use the factory bolt.

 

[Fred W]

Aftermarket shocks tend to supply their own bolts for this location - you don't use the factory bolt.

Correct. But I only had a picture of the stock one, and the shoulder set-up still works the same.

 

[SacramentoMike]

Glad you didn't find out about that some other way.

 

[SkooterG]

How sure are you that your ace mechanic gave it a 'light' tap?

 

[sylvester]

Glad you didn't find out about that some other way.

That’s for sure. I am getting new part next week, covered under warranty. I had a chat with my mechanic again and he is said it was lightly tapped out.

The part will be with Traxxion Dynamics on thursday.

Can the part be examined in lab or under micro scope to see if quality was a issue?

 

[Mr Bill]

My guess is that the wrong bolt was used to hold this (the lower end of the shock) to the relay arm. The correct bolt (#28 below) has a shoulder that fits inside the larger diameter hole in the shock bracket and butts into the inside race of the relay arm bearing (#29). When the assembly is tightened up the side of the bracket with the smaller hole is sandwiched between the opposite side of #29 and the nut and washer (30, 31), which restrains the lower shock end laterally, but the large diameter end is not clamped and there should be no lateral (squeezing) force applied to this bracket.
OTOH if someone used a bolt with no shoulder then the tightening force of the bolt would be applied squeezing the bracket in a way it was not designed for.

Picture of the assembly from the parts breakdown:

My shock is back and I'm shocked to find I've got the wrong bolt for the bottom! There is no shoulder to go into the big hole on the shock cleavis.

I'm sure it's the same bolt that came on my bike and worked fine with the original shock that had a steel cleavis. Worked on the Wilburs shock also. I don't remember if it was a steel or alloy cleavis like the Penske that broke on me.

I've just ordered a new one and see they changed the part number for bolt #28 in your diagram

new part number 90109-10024-00

old part number 90109-10007-00

This is what mine looked like

 

[HotRodZilla]

My stock bolt will not properly work with my Wilburs. The bolts are built differently and fit the application differently.

 

[Fred W]

I believe that the Penske shock is different than the Wilbers in that the hole on the right side is larger in diameter than the right side (just like it is on the stock shock) so the Penske Shock does use the OE bolt. At least, as far as I can remember, it did for mine.

 

[Mr Bill]

My stock bolt will not properly work with my Wilburs. The bolts are built differently and fit the application differently.

I don't remember changing any bolts with the Wilburs install, but that was a long time ago with the original group buy. Does the Wilburs have a steel cleavis?

Looking at the 2003 repair manual the bolt looks like what I have now without the shoulder. I hope the new improved bolt comes in before the snow melts here in New England!

 

[Mr Bill]

I believe that the Penske shock is different than the Wilbers in that the hole on the right side is larger in diameter than the right side (just like it is on the stock shock) so the Penske Shock does use the OE bolt. At least, as far as I can remember, it did for mine.

I have the stock shock still and it is the same as the Penske. Just stronger single piece of bent steel for the cleavis. I'll get it right this time. Just ordered $98 worth of bolts and bearings.

 

[Bustanut joker]

I just had mine off 3 weeks ago an Fred is right on all counts.. Penske use's the factory bolt.

 

[Mr Bill]

I just had mine off 3 weeks ago an Fred is right on all counts.. Penske use's the factory bolt.

Don't tell Fred that! He'll get a big fat head

Thank's for the tips guys. I went into my barrel of old FJR parts and found the original shock that was replaced by the Wilbers. A ziplock plastic bag was next to it holding the original bolt I should have put on the Penske three years ago. I think I'll put everything back together before I forget where I parked the FJR.

Now I'm wondering what the person used to mount my old Wilber shock because I kept that straight mounting bolt. I sold the Wilbers to Kevin Daly in 2008 who very soon after crashed and trashed his FJR without mounting it. I can't find who he sold the shock to.

 

[Auburn]

I believe that the Penske shock is different than the Wilbers in that the hole on the right side is larger in diameter than the right side (just like it is on the stock shock) so the Penske Shock does use the OE bolt. At least, as far as I can remember, it did for mine.

For gen II Penske shocks, they use the stock bolt with the shoulder on it.

Here is a close up picture of the bolt. (Note: my bolt is greased with a marine grade moly just prior to install. I use this same moly based grease made by JetLube on all my dirt bike shock linkages and bearings. At the end of the season, they always look like I just put them in. The grease does not wash out in the mud and water. The reason for greasing the bolt is so it won't corrode to the inside if the bushing -piece #29 in the drawings above- that goes through the bearing.)

Here is a view of the bottom of the shock looking through the big hole that the shoulder goes through.

I don't think is is possible to put the STOCK bolt in wrong and get the nut started. I could be wrong.

 

[dcarver]

Good post Auburn