Frame cracked

[04fizzer]

I would leave insurance out of it. They are not going to cover a frame failure with no accident, they are only going to note it, and not pay for it if you get hurt.


It is most likely a inclusion, or a scratch that has propagated thru the metal.

Long Long Long drawn out story very short. Metal is a crystal matrix. Any where a cyclic load is present with damage it will attempt to repair itself. That is the common "beach mark" that is present when humans notice parts failure. It is always caused by some sort of stress riser. (usually a inclusion, micro bubble, cut, scratch or notch) The way to stop it is drill a hole at the end. This puts a nice round radius in the metal latice. It cant propagate any more and weld it back.

It could of been stopped a long time ago if it was noticed as a small crack. In reality the frame probably should never of been shipped. If Yamaha does not want to cover it, you are stuck.

Drill, V grind, and weld, or shell out for a new frame. I would not worry about a welded frame at all.

Buy and read this book untill it falls apart. Amazon.com: Engineer to Win (Motorbooks Workshop) (9780879381868): Carroll Smith: Books It will make you a more competent human. You will have a strong basic understanding of what metal is doing, and what you can ask it to do. Its just like having a strong understanding of what you can ask your bike to do when riding. You will tighten and choose fasteners better, and trust what and why you do.

I hope this helps you in some way.

Steve

Cyclical loading is a nasty, nasty thing. Even though a part seems strong enough (number wise), you throw cyclical/fatiguing stresses in there, and you're looking to cut the strength in HALF. This phenomenon was first studied after train axles were catastrophically failing (is there any other way for a train axle to fail?), even though the axles were designed properly by the standards at the time.

 

[abraxas]

That's it, on the right side of the frame. Had it welded this morning by a friend of a friend, who is an aircraft mechanic / technician.

He has a few ideas on why it cracked, i'm not saying anything until yamaha gets back to me. His opinion is different from theirs, but somehow everybody assumes wheelying. My ONLY mod on the bike was a sprocket which was accidentally ordered with 2 less back teeth, hence LESS able to wheelie.

It looks crap though, structurally it should hold, and if it cracks again, then strip frame and engine etc, which i'm hoping like hell to avoid, but it can be reworked if needs be.

Guys, check bolts for torque spec, and don't freakin wheelie this bike. Ever.

 

[abraxas]

Hello David

Thank you for taking your bike into Linex to have it inspected.

On inspection it has been seen that the bike has been crashed at some stage, and the lower engine mounting is loose. This has caused vibration between the engine and frame, and the most likely cause of the crack.

In light of the above, any repairs or replacement, would be for the owners expense.

Best Regards,
Alan North
Technical Manager
Yamaha Distributors
Tel : 031 710 6408

Crap.
Next bike will NOT be a yamaha. Please, somebody explain to me how a loose bolt causes the frame to fail?

 

[FZ6-ZN]

On inspection it has been seen that the bike has been crashed at some stage, and the lower engine mounting is loose. This has caused vibration between the engine and frame, and the most likely cause of the crack.

“most likely” is an open statement and not necessarily the root cause. The Technical Manager has openly admitted that they haven’t a clue what caused the frame to crack.

I know about a KLR that fell off of the back of a truck. It was repaired and sold as new. I wonder what would be said if its frame cracked?

I’m very disappointed in Yamaha SA for abdicating their liability.

FZ6-ZN

 

[Motogiro]

“most likely” is an open statement and not necessarily the root cause. The Technical Manager has openly admitted that they haven’t a clue what caused the frame to crack.

I know about a KLR that fell off of the back of a truck. It was repaired and sold as new. I wonder what would be said if its frame cracked?

I’m very disappointed in Yamaha SA for abdicating their liability.

FZ6-ZN

:Flash:
Not to be argumentative but......#1 - Didn't he (T.M.) say the bike showed evidence of a crash? #2 - Didn't he (T.M.) say the engine mount was loose? The engine on the FZ6 is an integral part of the frame so if any part is loose there's going to be a problem. Never saw where the technical manager said he didn't have a clue. He seemed to in fact, have three clues if you include "Vibration" which would qualify under cyclical stress.

 

[Nelly]

Very sorry to hear about this problem. I have been out to check my 2006. Fortunately no evidence of damage.
What model number is your bike mate? I wonder if the other guys bike was from the same batch?

Good luck


Nelly

 

[RJ2112]

Hello David

Thank you for taking your bike into Linex to have it inspected.

On inspection it has been seen that the bike has been crashed at some stage, and the lower engine mounting is loose. This has caused vibration between the engine and frame, and the most likely cause of the crack.

In light of the above, any repairs or replacement, would be for the owners expense.

Best Regards,
Alan North
Technical Manager
Yamaha Distributors
Tel : 031 710 6408

Crap.
Next bike will NOT be a yamaha. Please, somebody explain to me how a loose bolt causes the frame to fail?

NC is right on it..... this frame is not a solid beam of aluminum, and it's designed to handle stresses in a specific way. The loose engine mount takes away a very large amount of structural rigidty.... almost the same as taking away a tower supporting a bridge.... it may stand up for a while afterwards, but the rest of the structure is taking loads it was not designed for. Even if the total deflection is measured in millimeters, that will cause damage over time.

I would not want to try and weld that part without removing the frame from the bike..... it really needs to be welded from both sides to make it 'right'.

If the repair is that involved, it would be just as easy to install a replacement frame member that does not need the repair; if one can be located with low enough expense, I would consider that as an option were this my bike.

 

[abraxas]

RJ2112, thanks for your response.

Acoustic resonance is basically what Yamaha said, i think thats the same as cyclical loading?

It was an aircraft mechanic who assisted, and while he's aware of the problem, it's very odd to find that kind of effect on a motorcycle.

His take was that it was the steering head bearings that caused this. Yamaha didn't notice that (?). They were loose, and overdue, and the difference today is phenomenal. I think i can understand how that caused a problem, but it doesn't happen on all bikes, so somewhere yammie missed a trick (imho).

My bike is on 90 000km, and is actually becoming high maintenance. When it's not servicing or tyres, it's constant repair and such. Since i'm still paying for her, i can't do anything extra, and most likely i'll still be keeping her for a long time.

But i have lost the "total faith" i had. My bike has been kept stock standard, out of respect for the yamaha technicians. No more. She now be my bitch. :rockon:

Sprocket was first, longer legs, next is performance air filter. Maybe rip the cat out the cans too. :Flash:

 

[RJ2112]

Anytime resonance is mentioned, there is cyclical load involved. Something is flapping back and forth. As this frame is an aluminum casting, it's very light... but actually quite brittle. Cast parts are not as strong as forged ones. (at least where fatigue is concerned)

A forged part is stamped, and that stamping process concentrates the material at the surface.... many of the small cavities, and surface cracks are welded together by the impacts. Cast parts do not get that, so there are more microscopic faults that a crack can start from.

 

[CrazyBiker]

Several, several reports of the sister FZ1 having frame cracking. (search the FZ1 site) Yours is the first FZ6 frame cracking report I've heard of. Do you do wheelies? I wonder if your bike was "normal usage." Certainly is disconcerting if not.... Maybe this is why Yamaha dumped the frame on the new FZ6R?

There are no several reports. Maybe 1 in a 1000 cracked. Don't spread incorrect crap.

 

[RJ2112]

There are no several reports. Maybe 1 in a 1000 cracked. Don't spread incorrect crap.

Wouldn't 1 in 1000 matter, to the 5 people who had cracked frames in 5000 units sold? What if it's 10,000? Do 10 bikes count as several?

 

[FZ1inNH]

Wouldn't 1 in 1000 matter, to the 5 people who had cracked frames in 5000 units sold? What if it's 10,000? Do 10 bikes count as several?

Regarding the cracked FZ1 frames, it was a cery small production run error where the frame was welded by the robotic arm with only one pass and not the
required three passes. While I do not know how many of those frames went out on the showroom floors or what year it was done in (assuming 2006), it was caught and corrected. Unsure if actual numbers were ever released on how many were sold before they corrected the issue, but there have been none since that time.

Also, it is VERY easy to determine if you have a correctly welded frame on the FZ1 with a quick visual.

What concerns me about the FZ6 crack is the location. Isn't it where the frame should be solid, meaning there are no welds or joints there? If so, there isn't an excuse for that where the FZ1 did have an excuse (and Yamaha owned up to it).

 

[RJ2112]

Regarding the cracked FZ1 frames, it was a cery small production run error where the frame was welded by the robotic arm with only one pass and not the
required three passes. While I do not know how many of those frames went out on the showroom floors or what year it was done in (assuming 2006), it was caught and corrected. Unsure if actual numbers were ever released on how many were sold before they corrected the issue, but there have been none since that time.

Also, it is VERY easy to determine if you have a correctly welded frame on the FZ1 with a quick visual.

What concerns me about the FZ6 crack is the location. Isn't it where the frame should be solid, meaning there are no welds or joints there? If so, there isn't an excuse for that where the FZ1 did have an excuse (and Yamaha owned up to it).

The frame is not a 4" thick piece at that point.... it's roughly 1/4" thick, with a number of ribs stiffening it in that area in a 'web'. This crack looks like it traces right along the joining of one of those stiffeners to the 'face' of the frame.

 

[FZ1inNH]

The frame is not a 4" thick piece at that point.... it's roughly 1/4" thick, with a number of ribs stiffening it in that area in a 'web'. This crack looks like it traces right along the joining of one of those stiffeners to the 'face' of the frame.

So, would you say this is a casting issue or, is that area welded and the weld is broken?

Regarding the FZ1 frame, the point where it was welded? It is two rectangular tubes with a smaller insert inside. The two halves are mated and the entire circumference was to have one weld directly on the seam and then one to each side of the first weld. The robot only made the single pass on the seam which wasn't enough to hold up to the stress.

Both can be fixed by a decent welder who knows his stuff with aluminum. While Yamaha owned up to those FZ1 frames, reports are that the few who had the problem took months to get their bike back. It might be worth a few bucks to just go get it welded and not be without the bike for so long. Weld, grind and patch it with some matte paint.

 

[RJ2112]

It's hard to say it's a casting issue..... certainly not a welded part, either.

The giveaway is how straight that line is. The outer face of the frame has a stiffener right at that point that goes towards the center of the bike.... 90° from the face of the frame. Should look a lot like the dividers in a cardboard box used to move glasses, or such. A thin rib, on edge. Cast as one piece with the facing element.

The reason I don't say it's a casting problem, is it's probably a very good, uniform casting.... but the whole (crystalline) structure is not designed to flex in use, along the line it did.

If it were me, and I wanted to weld that crack, I'd very much want to see it from the other side. I suspect the spacing is very tight to get a grinder in there to Vee out the crack to re-weld it..... even after you take the frame off the bike. My guess is the crack would be along the bottom of a 4 or 5" deep 'stringer'. Without knowing the spacing to the adjoining stringers, it's tough to say if you have 4,6, or 8" of space to work with.

 

[CrazyBiker]

Due to that location I would also be worried if the swingarm was torqued well and regularly checked. The rider weight maybe the concern too due to the forces applied to the ground from the subframe and back from the swingarm. more like a >| ==> >', transformation.

 

[sonic]

I'm way late to this thread, but it seems that the moral of the story is to spend an hour several times a year to check that everything is torqued properly?

 

[abraxas]

I would double that. Check, torque, recheck, re-tighten, everything, often.

 

[abraxas]

This just keeps getting better.

So the weld cracked again. Took it back, the guy did a HUGE weld, looked strong enough ... then i dropped her.

Pulled out a petrol station, stopped at exit, here where every car leaves it's one drop, on the shiny slippery "stop" painted on the ground. Crunch.

Plastics on the left side stuffed. Problem for another day. The weld cracked.

Now i'm looking at this and saying wtf, it appears that falling on the left hand side of the bike, causes the frame to crack on the right. It fell off it's stand on the left once before, and is IMHO an entirely likely reason for the frame having cracked initally. Now yamaha has half a point, in that the bike has gone down, hence they wash their filthy fingers of it.

But now i ask those who know more than me:
Is it possible that the bike falling over on the left could damage the frame on the right? (i have no frame sliders, and the engine was scratched)
If this be so, surely there are HUGE questions to be asked about ANY vehicle that suffers catastrophic frame failure from falling over?

All bikes fall at some point, but frame failure from a 0 km/h fall sounds remarkably like design fault. I am looking to do something, anything, but since the plastics are messed, i can't even sell her. And riding her is just causing the same problem repeatedly.

Guys i haven't been on a breakfast run for months now, and haven't pillioned anyone either.Wife and kids not happy. This is just starting to eat me alive. WTF do i do?

Any suggestions ideas comments would be greatly appeciated

 

[FZ1inNH]

If it were me....

I would strip the bike and get the frame completely bare. Then I would have a reputable welder add a reinforcement bar inside and weld there, plus grind all prior welds and bead the area all anew. Simply welding the outside while the bike is whole is no more than a bandaid fix.

The stress of falling over and a weak weld? Yes, totally possible to crack it. This means the weld wasn't good to begin with. Don't go back to the same person because if a welder is worth his salt for structural welding, he'd not have let you drive off with that weak of a weld.

Plastics... How bad? Pics? Perhaps you can get the FZ1N kit and go naked? Might end up being cheaper. Unsure of pricing in South Africa and if parts are readily available. You can always watch ebay for deals of try and work with members here who are going naked and parting out. They seem to do this on a regular basis.

Sorry it happened to you but I'm glad it cracked merely falling over rather than you and a child out on the road and having a catastrophic failure!