My '03 may have seen her last miles.

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I have taken apart many engines. Lack of oil can heat a crankshaft damn fast, think about the rpm it was turning. Any oil loss would trash this quickly. Care to drain your oil and rev it to 5000 and then shut it off? At the point that it started "losing power"it was actually seizing up. For an example of the friction involved. An excavator can actually spin the bushings in the arm if the bucket pins are not lubricated. Then the lube holes no longer line up. And they turn very slowly compared to a motorcycle engine. If the rod bearings for # 3 spun, at that point carnage is imminent. Quickly. A hell of a lot of friction with no oil. And at 5 psi as mentioned above it would not take very much excessive clearance.

I would love to personally inspect this engine but that is impossible and does not really matter anyway. It lived it's life until it died.

 
I strongly believe that something has clogged an oil passage..An excessive clearance between the metals i don't believe that can cause a damage like this immediately in seconds..

An excessive clearance between the metals can cause more excessive wearing,but i don't believe again that can cause this damage immediately in a few seconds!

Whatever happened,happened in a few seconds,and i don't believe that the excessive clearance between the metals caused this damage in a few seconds..This damage looks like that between the metals there was a completely lack of oil..So for that reason the deformation of the connecting rods..

My opinion..


A question,this happened after a loooong wheelie..?
rolleyes.gif
Also,as ''RaYzerman19'' asked,let us know what oil filter was on the bike,how many kmiles was there and what oil you use?
No, this was after about an hour and a half on the road, just going down a State Hwy at 70mph.

It was a Wix filter and I have mostly used Rotella T 15w40 oil.

Grady
Sounds to me like the rod bearing was getting cooked for awhile. Look at the discoloration of the crankshaft where the #3 and #4 rod bearings ride:

5F98A554-8846-46BC-9DE4-D997C63F0940.jpg


To me, that doesn't look like it happened quickly, it took awhile for that heat to build up in an otherwise oily environment.
You can see the heat discoloration at the failure points (and nearby) big time on the crank...

Next to crank gear(just above), it almost appears as if a rod bearing melted itself to the crank(just to the right of the oiling hole).

 
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Could an oil pressure light, rather than the FJR's oil level light, perhaps have saved this, or at least limited damage to repairable bearings/journals? I suppose that depends upon where oil pressure is measured. As I think about it, probably not.
I think part of the problem with an oil pressure light/gauge would be convincing the potential owner(s) that having less than 5 psi of oil pressure warmed up at idle is normal. It's in the service manual, check it out.

Were the bad rod journals the farthest from the oil supply passage inlet? May just be that do to excessive oil clearance in the others that no oil was left to get that far. Then again, if it was that bad I would think it would have had rods knocking before going.
Here's what (half of) my crankcase looked like when I split it open:

[img=[URL="https://i75.photobucket.com/albums/i287/leavy1/Bike/FJR%20Transmission%20Disassembly/SAM_0637.jpg%5D"]https://i75.photobucket.com/albums/i287/leavy1/Bike/FJR%20Transmission%20Disassembly/SAM_0637.jpg][/URL]

The gallery that feeds the main bearing journals is directly beneath the main bearings, and oil is delivered from the main bearings to the rod bearing journals through passages drilled in the crankshaft. The damaged journals on dunhamg's bike were the rod journals of cylinders 3 & 4, which would be on the right side in this photo. What feeds the main bearing gallery is the gallery that runs perpendicular to it. That's where the pump pushes oil through the filter and oil cooler before feeding the mains.
What is the back story on this one?

Grady
2nd Gear. Twice. Second time I had the two corresponding brand new gears undercut so I'm pretty damn sure there won't be a 3rd time.

Was your trans popping out of any gears? I saw some fork damage in one or two of the pictures you posted.

The more I think about your engine, the more I think you lost clearance on the crankshaft main bearings from time/wear/beating on it. That would prevent oil from reaching the rod bearing(s), if it can't develop enough pressure because oil is pissing out of the worn main bearing. I do think your engine is definitely a statistical anomaly. Got any plastigage?
No, never had an issue with the transmission on this one at all. Not for lack of abuse ;)

Grady

 
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