Would be worth a closer look at the two break points.

I would doubt if they broke at the same time.

One will be a different colour to the other.

One will be a 'clean' crack , the other will be torn apart.

This may give you a clue as to how long it had been running with a fault before the hard acceleration finished it off.

I agree with JH regarding the need for close inspection of the breaks … but I aso wonder if anyone has looked at the sprockets.

I would not be surprised to find evidence of a small stone, or some other highway debris, being trapped between sprocket and chain.

MichaelG.

Edited By Michael Gilligan on 29/05/2017 13:31:02

Crystalline fracture, these links are mass heat treated and maybe very close to their limit and size. Then the pins are interference fit to the links and maybe this one was a bit hard? Ergo, cracking until extreme stress occurs.

Clive

I've had this happen once with a Regina Gold chain but never on a road bike, the chain went back it eventually came back with the explanation that the chain was run over tight, I doubted this so checked and they where probably correct, after thinking on this for a while I realised this happened during heavy acceleration but was more than likely caused a little earlier (about 100yrds) because the suspension bottomed out after the jump at Cadwell park, this tends to happen more on motocross bikes for the same reason.

My suspicion is this chain was adjusted too tight at some point and it simply failed later, dealers are notorious for not doing what they are paid to do, as for the 200hp these are more or less irrelevant figures, on a dyno these bikes can produce close to these figures but in the real world never do, traction control anti wheelie, and manufacturers in built restriction in all but top gear simply stop this happening, I've made parts for and ridden several WSB race bikes (not in anger I must add), for Yamaha and more recently BMW none of which produced 200bhp in rider trim, they are simply mind blowing things to ride, don't get me wrong, they can produce more than 200 bhp but the riders find it unmanageable and just end up going slower as a result, and when you look at the data logs from the bike rarely do they use full throttle, this will be apparent in the next few weeks as the TT unfolds, some riders go faster on the 600's as opposed to the superbikes.

First tell us make of bike and name of dealer. They don't like negative publicity. As long as what you say is true it cannot be libelous. Ask dealer to explain link between engine power output and load on alternator. There isn't one. Then contact manufacturer, then go to small claims court

I once had to contact manufacturer in Japan before UK dealership would help with parts. UK branch of manufacturer could not do enough for me after that one contact. Japanese do not like contemplating "loss of face".

Was also thinking there might have been some fretting between the pin and the hole that exacerbated things.

My first thought was fake chain. There is a MASSIVE problem at the moment with fakes entering even the legitimate supply chain, but at 1200mls this has to be the original OEM.

I can't find out who makes them for Kawasaki, is it Tsubakimoto?

My second thought was overtight. At 1200mls it means either someone rode it home from the dealers & inside 1200mls have over adjusted the chain . . . Or the stealership employs training scheme youngsters to uncrate, PDI, first service & doesn't keep too close an eye on them.

Seasoned spanner monkeys will tell you that as much as 90% of owner rider maintained chains are over tight to some degree, are either bone dry or gunked up in grinding paste !

My third thought was a rare manufacturing defect. Rare, but it does happen, recently a major aftermarket manufacturer had issues & promptly blamed it on fakes.

My gut feeling is someone's overtightened it.

Does Shaun let you ride the race tackle or is it strictly the spare bikes?

Haven't had time to read all the posts, so apologies if I'm repeating.

I would check the sprockets for indentation or other damage from a foreign object – it's unlikely to be a road stone as they're pretty soft but I'd go with the damage caused prior by over tightening then it was an accident waiting to happen.

Sounds like rider and engine casing are largely unscathed, I hope that's an accurate assumption and all is well.

One last observation.

Look at the two 'colours' at the end of the pin which holds the two outer plates together.

Bright metal nearest the camera, blue oxide on the other side of the pin.

Normally , this pin is swaged into the outer plate and does not move. The roller does all the moving round

the pin.

But, the bright bit suggests a fair bit of movement took place between the outer plate and the pin.

Like might have happened if it had been cracked for a little while.

The crystalline nature of the fracture usually indicates one of three things:

1. Brittle failure (too hard/not ductile enough) and subject to a shock loading
2. Actually not hard enough, causing a fatigue failure at too low a stress.
3. Simply over stressed.

I assume the shock loading didn't occur when driving sedately, so that rules 1) out. The fatigue load would have been expected to happen on one side of the chain only, with the bit on the other side hanging on after the side with the fatigue crack broke. Now, the fatigue crack could be microscopic & the photo isn't really good enough to completely rule this out, but it does seem unlikely that both sides show the same crystalline failure from a fatigue crack at the same time.

Which leaves 3) as the most likely failure. The remaining part of the link could be hardness tested to find a likely range of failure stresses for the link considered, and a stress engineer could then calculate the applied stresses in various scenarios, and see whether there is a mis-match. I suspect that the dealer will never be convinced, regardless of the weight of evidence, particularly if the evidence proved Kawasaki has supplied sub-standard parts. That is too much like an admission of legal liability.

I think you are on a hiding to nothing in trying to prove it, but reckon the parts were probably sub-standard. The rear wheel should break adhesion long before the chain breaks. On the other hand, if the chain was over-tightened, then another indicator could be to check the bearings. Is there damage on the wheel bearing/gearbox output shaft on the side of the bearing housing where the chain would have pulled it. There may be some sign of pitting/scoring in the surface where the balls/rollers would have been under maximum load. And if they don't show the damage yet, they might well show it at 20000 miles, even if the damage originated in the first 1200.

Regards,

Richard.