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On one of the FJR forums, a member grenaded his engine about 170 miles after doing a cam chain and tensioner change out. I suspect (and he posted) that he could go back and forth by one tooth (and likely assembled the bike with one tooth off).
The point, doing some research, I found that the cam chain tensioner, for the FZ (year 2007 and 2009) not only have different part #'s, but look differently in the parts fisch...?? News to me!
Reading the below post, (again this is from an FJR forum), shed some light into the workings of the Yamaha tensioner. Apparently there is no racheting safety inside, strictly spring pressure only. The updated FJR tensioners, besides have a stiffer spring also have a longer plunger so it can extend out further.
Here is the link for further reading:FJRF008: Cam Chain Tensioner Survey - Technical/Mechanical Problems - FJRForum
In a nut shell, quote:
There have been numerous posts and questions over the years of this forum’s existence concerning noisy cam chains, due to the OEM cam chain tensioner not being up to the task.
There have also been documented disastrous results from cam chain tensioner failures, resulting in destruction of the valve train and expensive follow-up repairs. Incidentally, all four documented cases of catastrophic cam chain tensioner failures involved 2004 model motors, however there easily might be other, forum-undocumented failures resulting in engine damage in other model years.
A cursory examination of past posts involving cam chain noise emanating from the right side of the motor indicates the original OEM cam chain tensioner (hereafter referred to as CCT) has a finite life, although Yamaha doesn’t suggest a maintenance or replacement schedule for the original part.
However, there seems to be an indication that Yamaha is aware of a problem, considering a recent design and part number change for the OEM unit with forum members who have replaced their OEM unit with the updated model indicating the new replacement part incorporates a longer shaft in the adjustment mechanism, providing more extension of the adjusting shaft at less spring deflection, effectively improving the capabilities of the design, and possibly providing a longer MTBF (mean time between failure) for the OEM replacement .
From my investigations, reported cam chain noise has come as early as 7,000 miles, or as late as over 110,000 miles, so there doesn’t seem to be a pattern for early failure in the OEM CCT. However, after reading many of the threads involving cam chain noise and CCT replacements, it could be deduced that many of the failure issues have immediately, or at a reasonably short time, followed a valve adjustment, where the CCT had been retracted for cam removal.
To my knowledge, there is NO updated (blue dot-as there is for the FJR) CCT for the FZ6. Life of the CCT (and your engine) is dependant on that spring inside the CCT. Should it break (unlikely) suddenly while running, your engine is likely toast. Most often, you start hear a rattling. Seems that replacement of the CCT, ASAP, would be warranted to prevent a catastrophe.
I posted this not to scare anyone but to make them more aware of the potential for a failure, especially the older the bikes, higher mileage, etc.
Please don't ignore any new noises, especially from the right side of the engine.
As a side note, the FJR cam shafts, cam chain, guides and tensioner set up is about identical to the FZ6. I suspect the chain is slightly longer being a taller engine due to the increased displacement (I've never measured one chain next to the other).
Ride safe...
The point, doing some research, I found that the cam chain tensioner, for the FZ (year 2007 and 2009) not only have different part #'s, but look differently in the parts fisch...?? News to me!
Reading the below post, (again this is from an FJR forum), shed some light into the workings of the Yamaha tensioner. Apparently there is no racheting safety inside, strictly spring pressure only. The updated FJR tensioners, besides have a stiffer spring also have a longer plunger so it can extend out further.
Here is the link for further reading:FJRF008: Cam Chain Tensioner Survey - Technical/Mechanical Problems - FJRForum
In a nut shell, quote:
There have been numerous posts and questions over the years of this forum’s existence concerning noisy cam chains, due to the OEM cam chain tensioner not being up to the task.
There have also been documented disastrous results from cam chain tensioner failures, resulting in destruction of the valve train and expensive follow-up repairs. Incidentally, all four documented cases of catastrophic cam chain tensioner failures involved 2004 model motors, however there easily might be other, forum-undocumented failures resulting in engine damage in other model years.
A cursory examination of past posts involving cam chain noise emanating from the right side of the motor indicates the original OEM cam chain tensioner (hereafter referred to as CCT) has a finite life, although Yamaha doesn’t suggest a maintenance or replacement schedule for the original part.
However, there seems to be an indication that Yamaha is aware of a problem, considering a recent design and part number change for the OEM unit with forum members who have replaced their OEM unit with the updated model indicating the new replacement part incorporates a longer shaft in the adjustment mechanism, providing more extension of the adjusting shaft at less spring deflection, effectively improving the capabilities of the design, and possibly providing a longer MTBF (mean time between failure) for the OEM replacement .
From my investigations, reported cam chain noise has come as early as 7,000 miles, or as late as over 110,000 miles, so there doesn’t seem to be a pattern for early failure in the OEM CCT. However, after reading many of the threads involving cam chain noise and CCT replacements, it could be deduced that many of the failure issues have immediately, or at a reasonably short time, followed a valve adjustment, where the CCT had been retracted for cam removal.
To my knowledge, there is NO updated (blue dot-as there is for the FJR) CCT for the FZ6. Life of the CCT (and your engine) is dependant on that spring inside the CCT. Should it break (unlikely) suddenly while running, your engine is likely toast. Most often, you start hear a rattling. Seems that replacement of the CCT, ASAP, would be warranted to prevent a catastrophe.
I posted this not to scare anyone but to make them more aware of the potential for a failure, especially the older the bikes, higher mileage, etc.
Please don't ignore any new noises, especially from the right side of the engine.
As a side note, the FJR cam shafts, cam chain, guides and tensioner set up is about identical to the FZ6. I suspect the chain is slightly longer being a taller engine due to the increased displacement (I've never measured one chain next to the other).
Ride safe...
