Broken Penske Clevis.

[Fred W]

Shaving the outside of the clevis yoke will weaken it somewhat, and since that is the part that is failing I think we all wanted to avoid anything that would reduce the strength of that part any further. Granted, the failures are not in the location you suggest, so maybe that is a viable option

Probably the better solution is to shave the hex head of the shoulder bolt, as was already mentioned previously. That would essentially create a longer shoulder to contact the inner bearing race, and also not reduce the penetration of the 12mm shank of the shoulder bolt into the 12mm hole in the clevis, like a shim would. You would be reducing the strength of the bolt's hex head, but the nut on the other end is not highly torqued and the will be no tension on the head when in use.

The hang up on doing that is that not everyone has a lathe or mill handy, but I may have come up with a Rube Goldberg way around that. If you were to chuck the bolt up in a drill (or drill press) you could use a flat file (ideally one with a smooth side) to shave enough of the hex head to accomplish what we want.

 

[jammess]

Hi Fred I see your point. That said shaving the bolt head means you would have to buy a new bolt if you change the shock again. Is this bolt hardened? Taking a bit off the outer clevis surface just modifies the Penske after market shock and as you say this mod isn't in the area known to fail.

I don't think i'll ever be in the market for a Penske shock.

 

[Fred W]

No, the bolt isn't hardened. Guys with lathes have reported the heads are easily shaved. Wjem I was searching for solutions, I also saw a technique when a guy used a lather to turn a hardened part and a dremel with a fiber reinforced cutoff wheel on it to part it. Lots of creative ways to remove metal out there.

After the bolt has been modified it will still work just fine in the stock shock. There would just be some added space between the outside of the steel yoke and the head of the bolt Even if you wanted to restore it to stock spec, the shoulder bolt is only ~ $3 - $4.

 

[HelzBelz]

I am going to do two things, while waiting for Penske to solve this:

1. I am going to order another bolt. I am going to remove some of the shoulder as previously suggested. This will act to lengthen the bolt.

2. I am going to order another spacer, and I am going cut off an amount of that new spacer to be a shim to lengthen the existing spacer, which will limit the the amount of pinching that can be done when tightening the bolt.

This is, in my opinion, what needs to be done. I base this on all of the great work and ideas shared here. The biggest problem I have with Penske is that I don't think they are logically thinking about this yet. The engineers that approved this application assumed that that it would work just like the stock shock, with the stock bolt and sleeve/spacer/etc.. They were happy with that design. The only problem is that the bolt and sleeve arent long enough. so their solution: "put the R6 clevis on our shocks with the R6 bolt, hopefully that should work, once we get our hands on an R6 bolt to try it". Because spec'ing the correct replacement bolt and sleeve is apparently an impossibly hard task.

Once i see how long it takes to get these parts, I'll likely change my mind. especially if its not snowing in these parts.

 

[Mr_Canoehead]

This sounds like the perfect time to buy a mini lathe. $1000 to fix a $3 bolt? Makes sense to me!

 

[eflyguy]

It's the excuse I've been waiting for...

 

[Niehart]

jammess, I have 250,000 miles, 3 bikes and 4 rebuilds on Penske and it's still going strong.

 

[jammess]

Evening Pie Smuggler, That says a lot for Penske. Now if they (Penske) would step up and help solve this clevis issue for these folks that would be decent and maybe they will. It doesn't appear to be a Yamaha problem.

 

[Fred W]

I would agree, they are very good shocks. Totally transformed my '05 once I got it dialed in.

I bought mine used, rode it for 20k miles in the worn state, rebuilt it and rode it another 30k miles with no problems. It may be due for rebuild again, but it now belongs to my son and he doesn't ride all that hard yet. It's still way better than a stock shock even in its worn state.

It is a bit perplexing that they didn't do a better job of integration with the FJR considering the number of units sold over the years. But I'm sure that the guys that design and approve the install hardware are not the same guys that designed these great shocks. It's well worth your time to get the shock adapted correctly to your bike. You will not be sorry in the long run.

 

[HelzBelz]

Playing around today. I have the 8975..

I went to the hardware store, picked up a M12x60mm hex head partially threaded bolt, and matching nyloc nut.

for a new/additional collar/spacer, I had to settle for a collar that was 1/2' id x 5/8' od (roughly 13m id, 16m od). Not perfect, but I am awaiting a the yamaha spacer from partshark.

I inserted the M12 bolt through the small hole side, basically backwards of the way the stock bolt would work, with oem spacer in place and then extended the OEM spacer with about 71mm of the aftermarket, poorly fitting, spacer on the thread side (big hole) side of the bolt. This provides a shoulder for the big hole, albeit 1mm smaller than we really need.

Tightened it down till I could see 3 threads. This should not have pinched the clevis, as is evidenced by the new visible gap of about 1.2mm. I rubber malleted the shock gently right and left before finally measuring the gap. Needless to say this is not going to bind, although the amount of crud that will get in there is scary, especially worrisome because the spacer is now two pieces, making it entirely likely that the bolt will experience more moisture than ever before.

When my new OEM collar shows up, I am going to cut 71mm off of it as cleanly as possible, and insert it in place of the poorly fitting spacer. I am also going to obtain a better quality bolt, maybe one of them high strength ones from McMaster (thinking maybe the flanged head JIS spec'd bolt)

https://www.amazon.com/photos/share/p3cuozN5SWF3ppw2afYHZOo47VnfbHLscWvqLwARwj3

https://www.amazon.com/photos/share/p3cuozN5SWF3ppw2afYHZOo47VnfbHLscWvqLwARwj3

 

[Fred W]

So, I finished doing my relay arm maintenance on my '14 ES this morning, and confirmed my prior suspicion that the ES has gone to. 10mm through bolt with a spacer that is 10mm ID and 17mm OD. I think this tells me the right move is what you propose, to use a 12mm x 60mm bolt, with a cut off piece of the bearing "collar" as a spacer on the bottom of thePenske shock. That setup will be totally adequate, and much better than using the stock A shoulder bolt. Then if Penske does come up with some other solution later on you are only about 5 or 6 bucks in hardware, and can adopt their solution.

 

[Panman]

Hi Fred I see your point. That said shaving the bolt head means you would have to buy a new bolt if you change the shock again. Is this bolt hardened? Taking a bit off the outer clevis surface just modifies the Penske after market shock and as you say this mod isn't in the area known to fail.
I don't think i'll ever be in the market for a Penske shock.

You should read the thread, as I stated dead soft.

 

[Fontanaman]

I sent this note to Eric at Penske today.

Hello Eric,


I have decided to have the stock bolt head shaved down on a lathe by a machinist to avoid bending the clevis.

I am not impressed with Penske's ability to provide an updated bolt to address this issue. I have waited all winter and a simple response to this email took a month. The one month response does not inspire confidence and trust Penske is serious about fixing this problem.

Jim Fontana

 

[lnewlf]

why the hey didn't Penske just make the space between the clevis legs a tight fit for the sleeve in the relay arm and just bolt the sucker in there ??....[like the Wilbers I just put on]..Meebee they didn't want to spring for a new bolt...

 

[eflyguy]

They didn't make this part just for the FJR.

 

[Fred W]

Actually, I think they may have.

In the Penske 8900 series Technical Manual that I received with my shock, it has the parts breakdown for the Shock Parts list. The fixture at the bottom end of the shock is either a heim joint type eyelet or clevis, each of which is model specific. Another pdf version of the 8900 series parts list that I found online (somewhere?) lists a bunch of different clevis options, none of which are dimensionally the same as the one that we get on the FJR version of their 8900 shock.

I am fairly confident that they made that clevis with the intention of being able to use it with the stock FJR shoulder bolt mounting, but they screwed the pooch on that design. I do agree that for the added cost of providing a bolt and self-locking nut, they could have simply provided a clevis with 12mm holes on both sides of the clevis that was a snug fit to the inner bearing race.

While visiting my son in VT this weekend, we took the time to climb under his still snow-bound 1st Gen and inspect the clevis. The good news is that his has not broken yet. Once he can get it down his dirt (now mud) road and ride it home, I'll be fitting it with a replacement 12mm bolt and a spacer that I will cut off from an old inner bearing race. I'll take some pictures and share what I did, of course.

 

[HelzBelz]

I sent another email to Eric as well on Friday, coincidentally. Even simpler than yours, just asking if any progress has been made. On March 21 he asked me for the measurement between the dog bones and said he thought he could have a fix quickly with that measurement. He's had that measurement from me since March 21st.

I have done 1000 miles on my makeshift 12mm bolt fix, with an ill-fitting collar extension. I have been meaning to pull it to see what it looks like now, but have been busy doing electrical stuff this past week. (Long story that ends with my new garmin needing a new battery sent from Garmin, and my install of a new centech ap2).

Pictures coming later today of what my bolt and a makeshift spacer look like after 1k miles.

I also have received from partshark a replacement bolt, and collar, so my plan is to head down to a machine shop this week and have them shave the some of the inside of the head off the old bolt, and cut a piece off my new spacer/collar as a proper add on. (I am toying with the idea of having them shave some of the inside of one collar and the outside of the the other so that they can lock together at exactly the right length, like the collar at the top of the shock.)

 

[airboss]

Well boys & girls.

I have a broken clevis.

Just got off the phone with Eric, Penske has a fix coming for our issue, A new design for the clevis and a bolt to match.

Mean While Eric will overnight a new clevis to get me home since I am only 1700 miles from Tucson.

Then he will send the new design clevis and bolt to me soon as they are available.

BTW all no charge,

 

[Fred W]

That is good to hear, Karl. Well the bit about the new design, not the part where yours is broken.

 

[HelzBelz]

my next question will be, is this quasi-recall "service" doable at home? Does that Clevis just twist out? (and is it different on my 8975 than it is on the other models). Guess Eric will let me know at some point.