Timing chain question

[Dwrat]

Question about failing timing chains.
Does the chain actually snap or is it the gear system that fails?
Is it from getting on and off the gas over and over?
I just don't see the chain snapping but can't find a picture anywhere.

 

[Neutron]

The chain breaks, not a gear failure

 

[Zizzou 192]

Question about failing timing chains.
Does the chain actually snap or is it the gear system that fails?
Is it from getting on and off the gas over and over?
I just don't see the chain snapping but can't find a picture anywhere.

From what I have read here when they do snap, it is not under strenuous activity.

But stuff just doesn’t just break for no reason.

The letting off the gas and loading the pump would cause some major force, and would likely add stress and stretch the timing chain, just like it would shorten the life of the supercharger clutch due to the boost pressure with no where to go. Except there is no clutch to protect the engine from a loaded pump. Interesting idea.

My guess is that Yamaha thinks it is primarily a lubrication related issue though since right after people started reporting an increase in broken timing chains, they came out with a free comprehensive engine warranty if you used and document regular yamalube oil and filter changes.