Ever seen this before?

[Kawtippin]

 Last fall while riding my FJR I had the simultaneous failure of the two dog bones on the rear suspension.  I was doing 75 mph in the fast lane of a three lane highway, leading a group of riders.  A perfectly smooth flat piece of highway when suddenly the rear collapsed. The bike dropped down, rear fender onto tire, locking it up.  I skidded 40 yards and melting thru the rear fender.  I managed to keep it upright and made it to the center lane when it came to a halt.  I looked back and saw cars and bikes coming at me.  Unable to move or put the stand down, I dropped it and ran to the shoulder.  Two friends ran into each other but miraculously the cars stopped. And this was at the height of leaf peeping season. Calls to Yamaha say a tech must inspect the bike so it is at a dealer.  I do all maintenance so Yamaha hasn’t seen the bike in ten years and they seem to think that keeps them free of liability.  I just want an answer as to how this could have happened?!?!19969F50-243E-42C0-A1E0-197085AD9FCD.jpeg

[Kawtippin]

[Kawtippin]

A friends dash cam caught it.

[Kawtippin]

[Fatfatboy]

Holy crap KT. That could of been all kinds of bad, especially if you had a passenger. I hope the guys that ran into each other are ok, as well as their bikes.

 I did a quick search and it looks like this has happened before. Doesn't appear to happen a lot. One site said something about it happens more in the UK because of all the nasty wet road conditions. The way I read it is the dog bones get stuck if they don't have enough grease on them and they snap.

I never realized the dog bones were so thin.


I'm glad you were not hurt. The world still needs KT.

[motogrady]

Holy crap KT.
Looks like the pivot bolt and bushing that go thru the linkage
are frozen/seized. The rust at the bolt head is the giveaway.  
Locked solid, or even really tight from lack of lube it’s the dog bones that were flexing when the swing arm moved, instead of the joint.  Gonna be a job getting that thing apart.

Dirt bikes, most nowadays all have a similar Linkage, setup, and require frequent tear down, clean and grease, as they are subject to massive mud and dirt being thrown on them.

I’d do the swing arm bushings when you do the linkage, they might be kinda dry also.  

Ya, dodged a bullet on that one for sure guy.

[Kawtippin]

 Yes, guys I got very lucky! Had this happened on a bend, forget it! And my better half almost, almost came for the ride! Plus.... we had just gotten back(both of us with gear) from a WV camping trip.  Yes, MotoG I thought about you! We stayed at a remote camp near Mt. Storm. Came home in pouring rain. We would have been killed for sure had it happened then.
 Anyhow....Yes, there is a needle bearing assembly that apparently seized.  And yes, Double F@ The dog bones are thin stamped steel!  And I saw the same thing online about it happening in the UK. I had just adjusted the rear. shock for the added weight for camping, but never inspected the dog bones.  I really never have.  Something I’ve never thought of.  So....now you better believe I will be checking!  Yes, I am also servicing the swingarm. While its with Yamaha, I figure go over everything. The bike os nearing 100,000 miles now.   Hope to have it back soon and answers from Yamaha.

[oldironnow]

Yes, glad the world still holds KT.

Amazing skill. Props.

I've been dropping into Carroll Smith's "Engineer To Win" lately. Noddling around in the metals and heat treating sections.

I would never let those pieces go. Especially get them back from Yam. Hang on to them. Personally, I would strive to get an analysis of the failure from a lab. I am curious to see the closest pic you can get of the failure area.

[motogrady]

Just a good thing you pulled it together with out going down KT. Really.

That area, Mt Storm, Thomas, Davis, is a hotspot real eastate wise lately.  
There is a Snow Ski resort kinda out there, in Cannaen Valley.  Warm months, a lot of motorcycle touring, winter they have snow skiing, all kind of close to the Balt/DC area.

Ya, some good riding out there.  

100k on the same bike, hats off to you on that one KT!

[m143]

I'm happy to hear that you rode that out.

[Kawtippin]

Yes, oldironnow, I will hold onto parts.   Bugs me that Yam is sounding like this is routine inspection.  I mean, I adj the shock and am aware that it is aging.  I inspect most things on the bike, as I do all maintenance.  I have been looking at all kinds of bikes, even obviously neglected ones, and the dog bones and linkage are all good.  Anyhow....a big reason for me posting this is just to remind you guys to take a peek at your set ups. You bet I will from now on. Also bugs me that the bike never gave me a hint of what was about to happen.  I carve a lot and never did it ever handle differently or make a squeak.
  As a kid I rode dirt, and all those instincts came right back and into play when this happened.  Up on the pegs I went and made sure to not make a sudden move. I believe I feathered the front brake and slowly shifted my weight down on the right side peg.  Angling to go from fast lane to shoulder of hywy.  I only made it to the center lane as the rear started to want to wag like a dogs tail. My buddies laughed as they said I even put on the right hand turn signal!  I did that because I was aware of the volume of traffic behind me.  Once it stopped in the center lane there was no way to hold it up.  The FJR had its back broken.  It fell on its side as chaos reined all around.  It took 5 or 6 of us to drag it to the shoulder and lift it on its stand.  
God was with me that day.
  Since then the Kawi has been filling in on our Sunday rides.  Many are amazed at the get up and go of that 500 motor, especially with a large pilot.... Lol! It is half the size and height of the bimmer GS’s that  it rides with. Fun nonetheless.   It will be good to have the Yam back. All work is done (I gave a laundry list of stuff to do since it was there) just waiting on the $125 rear fender to come in. On a slow boat from Japan.  I was thinking of fashioning a new one from a McDonald’s food tray.  Heat them up and cut them into whatever you need. But I went OEM with it.  

[Kawtippin]

Grado, we had a bladt from that WV location and struck out in many dirrections.  Fantastic riding! We went to that telescope you have there and the blackwater falls, Seneca rock.   We hope to get down your way again soon!

[m143]

Atta boy KT

[Fatfatboy]

Ever seen this before




Whizzer! That’s what it says on the tank anyway.  EJ Potter was the Michigan Madman, who stuffed a V8 into a motorcycle frame while in High School, and hit 130mph at the local dragstrip. He called the bike Bloody Mary, and raced it for 13 years on the national drag circuit, then started playing with aircraft engines - Allisons V12s for tractor pulls and a jet in a trike chassis (the Widowmaker - what black humor!), with which he set three land speed records. Hats off to EJ! [📸 wikipedia]


https://en.m.wikipedia.org/wiki/E._J._Potter

[motogrady]

^^^^

Am I mistaken, or are they Isolactic Motor mounts?

[Allred]

motogrady wrote

^^^^

Am I mistaken, or are they Isolactic Motor mounts?

As in dairy-product isolactic intolerant? :)

.

[oldironnow]

Iso-lack-tic

[oldironnow]

Let the photos play through to see the experimented with aero.

His left leg is lucky.


https://www.museumofamericanspeed.com/ejpotterwhizzerdragbike.html

[Fatfatboy]

“Potter would start the bike on a stand at the line at about 7,000 rpms, then when the green light came on he would drop the bike off the stand and away he went.”


That’s freakin nuts.






But oh so cool.

[Kawtippin]

Well, it was a long wait, but finally got the FJR back from Yamaha, complete with rear plastic fender.  No good answers from Yamaha California.  Looking at the dogbones you can see where it was bent and a crack was formed. I can see corrosion in the crack.  A friend and engineer who works for the Army as a metallurgist says it is classic for a stressed cast piece.  Apparently the table was set with that bend.  But how did it get bent??  
  Well, sheepishly I will admit to playing with some GS’s. I really subjected the bike to some hard, rock hits. I remember being amazed that the bike didn’t break.  It didn’t break then, but it started the clock.
 Upshot of this is to eyeball the structural suspension of the bike once and awhile.  Of course microscopic fractures will go unseen, but a bend and corrosion can red flag your attention.  
  Once I got the bike back I ran it thru its paces in the Catskill mountains.  The bike feels faster.  Guess thats to be expected after 6 months on the Kaw 500.  I really got to appreciate the 500.  It is such a fun bike and seems to want to please.  
 Waiting on a top case for the FJR.  Was going to ride 2 up to Montana this June, but now my back is saying not so fast.
Still hoping for less ambitious trips via the Yamaha this summer.  But Montana and Cali may be on four wheels with possible 2 wheel rental?  Anyhow.... figured I’d wrap up my tale of woe on a good note.  
 Who knows, maybe our paths will cross this summer, until then, be safe and ride like the wind!