Engine teardown after 90k miles

[art miller]

Interesting speculation!! Question; Does running at high rpm's hasten need for valve adjustment? I do not tend to rev the engine above 4000rpm. I generally up shift between 2500 and 3000rpm. The FJR has loads of power and revving it above that level seems like a waste of fuel and perhaps wear??

 

[tntmo]

I don't no about prior owners running a K&N filter, it had a stock Yamaha filter when I got it which was pretty dirty but not the worst I had seen.

This was an AZ bike, I never even met the guy I bought it from. He rode it to CA and it wouldn't start on him after he got here. A local shop looked at it, told him the news and he got a ride back home. He put up a craigslist ad, I went to the shop to check out the bike and then made him an offer. My son lives in AZ so he did the paperwork with the owner.

The bike didn't smoke when I ran it with the original engine, at least nothing noticeable. I didn't ride it enough to judge oil consumption.

I forget about shoveling snow, to think I was complaining about it getting down in the low 50's as I rode over the mountains the other day on the 350 mile ride I took. Ha!

 

[Geezer]

Interesting speculation!! Question; Does running at high rpm's hasten need for valve adjustment? I do not tend to rev the engine above 4000rpm. I generally up shift between 2500 and 3000rpm. The FJR has loads of power and revving it above that level seems like a waste of fuel and perhaps wear??

Based on what I have read, not scientific evidence that anyone had proven to me, the rings are designed to move radially in their grooves and work their way around the pistons over time. That movement helps keep the grooves clean and the rings free. By running the RPMs up and then closing the throttle abruptly you create the right conditions to encourage the rings to spin. That prevents them from sitting in one place where a little gunk can build up.

The way I like to ride the twisties is to generally keep he RPM above 5k so that I have plenty of power when I want it and good compression braking when needed so I rarely trail brake in a curve. I don't believe you can hurt the FJR by winding it up as long as you don't let the oil get low or the temperature get too high.

 

[hppants]

From what little I know mechanically, I concur with the OP. Recall that I disassembled Patriot's grenade motor with approx. 90K on it a couple years ago. If anyone is interested, here's the link to that:

https://www.fjrforum.com/forum//index.php/topic/151853-what-happened-to-isabellas-engine/?hl=+patriot++grenaded++motor

And here is the incredible story of how I got that grenaded motor and what this forum is REALLY all about:

https://www.fjrforum.com/forum//index.php/topic/150618-running-bad-feeling-blessedlimped-home-walking-on-air/page-1

I was very impressed to still see some faint hone marks in the cylinders, zero wear on the piston skirts, and ZERO wear on the cam lobes. Perhaps most impressive was that the transmission gears weren't even fully broken in - with still many machine marks visible.

It's easy to see how many have gone 200K and beyond. The motor won't wear out. Other parts of the chassis? Maybe, but not the motor.

BTW - there are still many parts left from the grenaded motor that are fit for duty. My standing offer still "stands". Anyone on this forum can have anything from that motor for free. You need only ask.

https://www.fjrforum.com/forum//index.php/topic/151951-isabella-motor-parts-the-pay-it-forward-thread/

 

[tntmo]

From what little I know mechanically, I concur with the OP. Recall that I disassembled Patriot's grenade motor with approx. 90K on it a couple years ago. If anyone is interested, here's the link to that:
https://www.fjrforum.com/forum//index.php/topic/151853-what-happened-to-isabellas-engine/?hl=+patriot++grenaded++motor

Great post, and glad to see you took pictures to document everything....which I didn't. These engines are impressive, and I'm a big believer in FJR longevity after getting intimate with the inner workings of her heart. I love bikes that you can put big miles on, I also have a Triumph Tiger that's got almost 95K miles on it.

Now, I can give you the good crankshaft and piston rods from this engine and you can build her back up again for another 100K miles.

 

[bergmen]

There is no doubt that it was run with a dirty intake system, I used over two cans of carb cleaner to get the throttle bodies clean. After the oil in the cylinders, it ran but it was obviously low on power. I didn't do a compression test after running it, wish I had. The shop didn't do a compression test, they did a leakdown test. The best cylinder of the four had 20% leakage, one at 30%, one had 90% and another had 100%.
I guess it would have been interesting to try Ring Free or some other product and see how long I could have ridden this bike, but for $500 (shipped!) I got a really nice used engine with 35k miles. I thought about rebuilding the engine but I decided it would be too expensive.

During a leakdown test you can listen very carefully to what is leaking. If exhaust valves, sound will eminate from the exhaust ports, intake valves, intake ports. If no sound is coming from either of these, then it is rings.

Dan

 

[tntmo]

There is no doubt that it was run with a dirty intake system, I used over two cans of carb cleaner to get the throttle bodies clean. After the oil in the cylinders, it ran but it was obviously low on power. I didn't do a compression test after running it, wish I had. The shop didn't do a compression test, they did a leakdown test. The best cylinder of the four had 20% leakage, one at 30%, one had 90% and another had 100%.
I guess it would have been interesting to try Ring Free or some other product and see how long I could have ridden this bike, but for $500 (shipped!) I got a really nice used engine with 35k miles. I thought about rebuilding the engine but I decided it would be too expensive.

During a leakdown test you can listen very carefully to what is leaking. If exhaust valves, sound will eminate from the exhaust ports, intake valves, intake ports. If no sound is coming from either of these, then it is rings.

Dan

The small bit of info I got from the shop said they heard air leaking from the oil filler port, meaning leakage past the rings. That's why I tried the oil in the cylinder trick and now I wish I had used some Ring Free or something else....just for the heck of it to see if it could have got the engine running better. I also wish I had done a compression check or leakdown test myself, but I had already jumped on the cheap engine deal so I sort of sealed my fate.

 

[bergmen]

There is no doubt that it was run with a dirty intake system, I used over two cans of carb cleaner to get the throttle bodies clean. After the oil in the cylinders, it ran but it was obviously low on power. I didn't do a compression test after running it, wish I had. The shop didn't do a compression test, they did a leakdown test. The best cylinder of the four had 20% leakage, one at 30%, one had 90% and another had 100%.

I guess it would have been interesting to try Ring Free or some other product and see how long I could have ridden this bike, but for $500 (shipped!) I got a really nice used engine with 35k miles. I thought about rebuilding the engine but I decided it would be too expensive.

During a leakdown test you can listen very carefully to what is leaking. If exhaust valves, sound will eminate from the exhaust ports, intake valves, intake ports. If no sound is coming from either of these, then it is rings.

Dan

The small bit of info I got from the shop said they heard air leaking from the oil filler port, meaning leakage past the rings. That's why I tried the oil in the cylinder trick and now I wish I had used some Ring Free or something else....just for the heck of it to see if it could have got the engine running better. I also wish I had done a compression check or leakdown test myself, but I had already jumped on the cheap engine deal so I sort of sealed my fate.

Yes, the oil filler port, I should have listed that as option 3. Good that they listened and gave you the info on the rings being the possibility.

Dan

 

[08FJR4ME]

Interesting speculation!! Question; Does running at high rpm's hasten need for valve adjustment? I do not tend to rev the engine above 4000rpm. I generally up shift between 2500 and 3000rpm. The FJR has loads of power and revving it above that level seems like a waste of fuel and perhaps wear??

Over 4K is a hell of a lot of fun though. You have to sacrifice something.

Dave

 

[Geezer]

Interesting speculation!! Question; Does running at high rpm's hasten need for valve adjustment? I do not tend to rev the engine above 4000rpm. I generally up shift between 2500 and 3000rpm. The FJR has loads of power and revving it above that level seems like a waste of fuel and perhaps wear??

Over 4K is a hell of a lot of fun though. You have to sacrifice something.

Dave

Yep. Might as well ride a 650 if you don't use the muscle of the FJR.

Regarding the need for more frequent valve adjustment, I haven't experienced that but that is a sample of one so it doesn't prove anything. Since the higher the RPMs are the higher the oil pressure is, I would expect that there is no additional wear cause by higher RPM. Using more power can be more stressful on the rings and cylinder walls, but that doesn't seem to be a problem with the FJR. Fuel economy is another issue. Spinning the engine faster is not particularly wasteful of fuel, though it may cost a small penalty in fuel economy. Many small swallows is about the same as fewer large swallows. Using more power uses more fuel because you are then taking larger gulps per revolution.

 

[kerlinger]

This has been a great thread to follow and I'm looking forward to viewing some of these images when i have more time....I've spent the better part of 10+ years flogging several Jap 600cc road bikes on the racetrack, with many not seeing anything more than an oil/filter change a couple times a season. Max RPM, missed shifts, downshifting when meant to upshift, clutchless shifting...etc These engines can take massive abuse with minimal maintenance. I'm new to big inline 4's - FJR - for street riding and will follow the suggested Yamaha maintenance schedules. For me, I certainly didn't buy it to lug, I sometimes bounce off the rev limiter in the first two gears when i'm not quick enough to bang a gear and when i'm in the mountains its 2nd/3rd gear and screaming. Understanding I'll pay the piper when and if anything happens, but I highly doubt anything will. And this forum continues to confirm how well built these bikes are.

thanks tntmo for this thread! good stuff here

 

[bergmen]

Interesting speculation!! Question; Does running at high rpm's hasten need for valve adjustment? I do not tend to rev the engine above 4000rpm. I generally up shift between 2500 and 3000rpm. The FJR has loads of power and revving it above that level seems like a waste of fuel and perhaps wear??

From what I remember reading, the FJR was originally designed to run wide open all day on the Autobahn. It wasn't originally destined for the US as I recall and only considered when we kicked up a ruckus. One look at the top down cooling system design shows intent on keeping the combustion chamber cool under maximum throttle. I wish all engines had a design like that.

Dan

 

[mcatrophy]

... Since the higher the RPMs are the higher the oil pressure is, I would expect that there is no additional wear cause by higher RPM...

Erm, no. There's a pressure relief valve, spec'd to 480-560 kPa (69.6-81.2 psi), so after this is reached, no further increase pressure with rising rpm.

 

[Fred W]

From what I remember reading, the FJR was originally designed to run wide open all day on the Autobahn. It wasn't originally destined for the US as I recall and only considered when we kicked up a ruckus. One look at the top down cooling system design shows intent on keeping the combustion chamber cool under maximum throttle. I wish all engines had a design like that.

I'm curious, what do you mean by "top down cooling system"?

There's a pressure relief valve, spec'd to 480-560 kPa (69.6-81.2 psi), so after this is reached, no further increase pressure with rising rpm.

The minimum oil pressure (at idle) is only 4.4 psi, so it must ramp up somewhat with rpm to hit that pressure relief. Not sure what rpm that will happen at.

 

[mcatrophy]

...

There's a pressure relief valve, spec'd to 480-560 kPa (69.6-81.2 psi), so after this is reached, no further increase pressure with rising rpm.

The minimum oil pressure (at idle) is only 4.4 psi, so it must ramp up somewhat with rpm to hit that pressure relief. Not sure what rpm that will happen at.

I think it would be reasonable to assume pressure proportional to rpm (all other things being equal), so 4.4 psi at 1050 rpm would need over 16000 rpm to reach 70-odd psi. So, maybe it's right that under normal operation more revs does give more pressure, it's only when cold that the pressure release valve operates. We can probably presume that the oil temperature doesn't rise significantly with sustained high rpm because it's cooled by the water coolant.
Yes, I was wrong in my doubt of Geezer's statement. Nothing new there, my wife is always telling me I'm wrong. Anyway, my apologies.

Of course, the actual pressure within the engine bearings is much higher than the pump pressure, all the pump is really doing is feeding the oil in the right places, overcoming "leakage". Also the engine relies on the oil for cooling all the rubbing bits as well as reducing friction.

From Wikipedia:

Local pressure (at the crankshaft journal and bearing) is far higher than the 50, 60 psi &c. set by the pumps relief valve, and will reach hundreds of psi. This higher pressure is developed by the relative speeds in feet per second (not RPM or journal size directly) of the crankshaft journal itself against the bearing, the bearing width (to the closest pressure leak), oil viscosity, and temperature, balanced against the bearing clearance (the leakage rate).

 

[bergmen]

From what I remember reading, the FJR was originally designed to run wide open all day on the Autobahn. It wasn't originally destined for the US as I recall and only considered when we kicked up a ruckus. One look at the top down cooling system design shows intent on keeping the combustion chamber cool under maximum throttle. I wish all engines had a design like that.

I'm curious, what do you mean by "top down cooling system"?

Well, after studying the manual I think I have made an incorrect assumption. I had thought that the coolant left the radiator (after being cooled) and entered the engine through the top tube that mounts to the valve cover and lowed down and out. It appears that this is incorrect and the coolant exits the engine through the tube set, then to the thermostat and then to the radiator.

Dan

 

[lele]

have you checked the Co2 setting in diAG screen? maybe the two low compression cylinders have this value too high..

 

[RossKean]

^^ ??? ^^

 

[lele]

too much fuel wash the oil from cylinders walls..

 

[SwollenRaccoon]

Interesting speculation!! Question; Does running at high rpm's hasten need for valve adjustment? I do not tend to rev the engine above 4000rpm. I generally up shift between 2500 and 3000rpm. The FJR has loads of power and revving it above that level seems like a waste of fuel and perhaps wear??

Sorry to get off topic (this is a great thread, by the way), and no offense intended, but you're kidding, right?