Engine teardown after 90k miles

Yamaha FJR Motorcycle Forum

Help Support Yamaha FJR Motorcycle Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Interesting speculation!! Question; Does running at high rpm's hasten need for valve adjustment?
From a theoretical standpoint, it should. The need for valve adjustments on a modern overhead cam, shim under bucket motorcycle engine like the FJRs is primarily required by wear at the valve face to valve seat interface, and that wear is due to the repetitive impact of the valves in their seats. Since at higher rpm operation the valves will seat more times per minute, and per mile, it isn't much of a stretch to deduct that the valves will wear faster per mile and require adjustment at a lower mileage.

However, valve wear, and the need for adjustment is not a big problem for these engines, regardless of how hard they are ridden. The reports from high mile FJR owners is that they may have had to adjust the valves once or twice in hundreds of thousands of miles. I really do not see the need to ride the bike like an old lady just to try to avoid having to adjust the valves a couple of times in that distance.

 
Last edited by a moderator:
Interesting speculation!! Question; Does running at high rpm's hasten need for valve adjustment?
From a theoretical standpoint, it should. The need for valve adjustments on a modern overhead cam, shim under bucket motorcycle engine like the FJRs is primarily required by wear at the valve face to valve seat interface, and that wear is due to the repetitive impact of the valves in their seats. Since at higher rpm operation the valves will seat more times per minute, and per mile, it isn't much of a stretch to deduct that the valves will wear faster per mile and require adjustment at a lower mileage.

However, valve wear, and the need for adjustment is not a big problem for these engines, regardless of how hard they are ridden. The reports from high mile FJR owners is that they may have had to adjust the valves once or twice in hundreds of thousands of miles. I really do not see the need to ride the bike like an old lady just to try to avoid having to adjust the valves a couple of times in that distance.

Thanks Fred. You have enlightened me. Art

 
Nice. Then the post was well worth making.

Enjoy the bike however it is that you do that most. You won't hurt it by riding it hard, nor by riding it easy. Take your pick.

 
I am curious what problems you encountered, especially with electronics, putting a 2010 engine in a 2005 chassis. Thanks, Phil

 
I am curious what problems you encountered, especially with electronics, putting a 2010 engine in a 2005 chassis. Thanks, Phil
There's a video on YouTube that pretty much sums up all the stuff you need to do. It's very easy though, swap a few things from the 2005 engine over to the 2010 and splice a couple wires. I also swapped the 2005 stator to the 2010 engine. I'm not sure that it was necessary, but the output was increased in the newer one and possibly needs a different voltage regulator/rectifier that's on the newer bikes. They also moved the regulator on the newer bikes.

 


Here's the link that shows a few of the things that you need to change to get the 2010 engine in the 2005. There was also a small engine mount above the shift shaft that was different. I just fabbed one up from some plate aluminum, but you can also purchase one.

 
TNTMO, have you gotten around to tearing the 05 engine down yet? Was it stuck rings? Intake or exhaust valves? Something else? How's the 2010 engine install coming?

 
Last edited by a moderator:
Top