Don't see one of these everyday in the ol' US of A

[Burns]

Well, that mechanic failed troubleshooting 101......
[/quote

odd that it is dry.

[racerrad8]

odd that it is dry.

Why is it odd?

Randy - RPM

[racerrad8]

Well, we got the XJR all dialed in. After getting the engine running properly the clutch was slipping badly. I also noticed every time I stood the bike up from the side stand, the front end would fall about two inches.

So, a new clutch and Barnett conversion installed and the forks were rebuilt. The left fork oil level was at 10" from the top of the tube and the right was 7 3/8" down. Both of the pre-load adjusters were adjusted to different rates as well. So, disassembly and rebuild back to factory specifications required. Now the front end is pretty solid. I only wish I had a set of 43mm RPM fork valves to drop in and the bike would be great.

So, my wife and went out for an afternoon ride and lunch. She is still getting adjusted to her new V-Star, but really likes it.

The XJR on the other hand is a flat out beast. It is amazing how the bike just lifts the front wheel with ease. Moderate accel in first and the wheel just carries as you control the throttle. If you snap it open then you are looking at the clouds in the sky. Shift to second and the front wheel still carries until you either let off or get to the red line. Then if you shift into third it still has a light front end as the speed climbs.

The lack of all that fairing and upper frontal weight, as well as the more upright sitting position just make the front end light on this thing...I was not expecting the big wheelie the first time it jumped up, it startled me as the headlight & handbars kept getting closer to my helmet. After that I was expecting it so I was able to use throttle control to just carry the front wheel.

The bike is fun to ride, but I do like the seating position of my FJ better.

I know the owner is going to be shocked when he gets the bike back as it has never run so good.

Randy - RPM

[Earl Svorks]

  Hey Randy,
That FJR is one fine looking machine. Not so much the #1 plug.
What I see is a plug that was dropped just before installation, by someone that failed to look at the damn plug before installing it.I see threads without a trace of lubricant. I see a crush washer that suggests the plug was not torqued up properly. I see the appearance of the same color and texture
produced by a spark plug cleaning device, of the media blast type.
  To me, this suggests there may be some other troubles with this engine. Over oiling, over fueling, weak ignition, , ?  You're the man who'll get to the bottom of it. 
   Cheers
   Simon

[FJ_Hooligan]

What kind of lubrication do you recommend for spark plugs?

I once used high temperature Never-Seize and it dried out so bad that I pulled the threads out of the head of 2 cylinders. 

I was able to repair the head with Time-Serts, but now I just give the plugs a quick shot of WD-40 before installation.

I have a small tube of high temperature lube that's supposedly specifically for spark plugs.  Problem is I can't get myself to trust using it.

[FeralRdr]

Hey Randy, what sort of usable range does the XJR have.  One of the things I always appreciated about the FJ was it's large fuel tank, which gave it long legs when getting decent fuel mileage.

[Earl Svorks]

 Regarding lube on plug threads, I have never had a problem arise out of using Never Seize in any of it's
varieties. I'd use it more often if it didn't seem to want to migrate onto everything around it,,, you know, 'Mechanic's tracks'. That said, the best lube is the one that actually gets put onto threads. A little grease, motor oil, chain lube, graphite even. Just don't leave it dry.
A spark plug, or just about any steel threaded plug or bolt or screw that mates with a hole in an aluminum assembly has a finite lifespan. Every time the fastener is torqued up, the internal thread is stressed to the point that it can cause the aluminum to flex a tiny bit. This will work harden the material , causing it to become brittle. This will end up with the threads shearing off and coming out with the plug, or whatever threaded bit used. Evidence of this can be found when you remove an engine cover. Run a finger over the mating surface, particularly over the bolt holes.The factory puts a slight chamfer on these holes but you can often feel a burr there from the threads pulling up . In places where the fastener is frequently overtightened ,like a spark plug, guess what,,,? Hello Helicoil.
Have you ever seen what happens when a Helicoil has been put in a blind hole and buddy does not remove the little installation tang?
  Cheers
Simon

[racerrad8]

Hey Randy, what sort of usable range does the XJR have.  One of the things I always appreciated about the FJ was it's large fuel tank, which gave it long legs when getting decent fuel mileage.

I don't know, I put about 100 miles on it, but never even paid attention to the fuel gauge.

Randy - RPM

[racerrad8]

 Hey Randy,
That FJR is one fine looking machine. Not so much the #1 plug.
What I see is a plug that was dropped just before installation, by someone that failed to look at the damn plug before installing it.I see threads without a trace of lubricant. I see a crush washer that suggests the plug was not torqued up properly. I see the appearance of the same color and texture
produced by a spark plug cleaning device, of the media blast type.
 To me, this suggests there may be some other troubles with this engine. Over oiling, over fueling, weak ignition, , ?  You're the man who'll get to the bottom of it.  
  Cheers
  Simon

Simon,

Yep, the other mechanic didn't start with the basics, he blamed on the new carbs the customer just bought from me...

The gap was not completely closed, but so tight the spark was too weak to fire the fuel charge sufficiently to run at idle. When the bike revved the higher voltage would then burn the fuel load but not fully.

As far as the lubricants, they are a no-no, at least with NGK plugs: https://www.ngksparkplugs.com/about-ngk/spark-plug-101/5-things-you-should-know-about-spark-plugs

The problem I see with anti-seize is as the combustion temps are enough to carbonize the oil of the anti-seize, the only thing left in the threads is the power metal component. that then galls the threads on the way out, pulling the weaker aluminum from the head.

Also, no they were not tightened enough to compress the sealing washer. That also does a couple of things. The plug is not tight and basically finger tight at operation temps due to expansion. The plug can then move around on the threads and also cause galling.

I cannot answer if they were cleaned, I really did not look that closely, I just properly adjusted the gap and re-installed since they were "brand new" plugs before the bike was shipped to me.

No engine troubles noted after all of the basics issues were addressed. the bike runs perfectly and the customer is happy.

Randy - RPM

[FJ_Hooligan]

As far as the lubricants, they are a no-no, at least with NGK plugs: https://www.ngksparkplugs.com/about-ngk/spark-plug-101/5-things-you-should-know-about-spark-plugs

The problem I see with anti-seize is as the combustion temps are enough to carbonize the oil of the anti-seize, the only thing left in the threads is the power metal component. that then galls the threads on the way out, pulling the weaker aluminum from the head.

Also, no they were not tightened enough to compress the sealing washer. That also does a couple of things. The plug is not tight and basically finger tight at operation temps due to expansion. The plug can then move around on the threads and also cause galling.

That's exactly what I experienced.  The plugs became increasingly harder to remove until they eventually pulled the threads out of the head.

I'll bet 9 out of 10 bikes I have worked on for friends had the spark plugs too loose.  The crush washer was not even deformed.  Plugs were essentially hand tight.

[ribbert]

Regarding lube on plug threads, I have never had a problem arise out of using Never Seize ....
Simon

Neither have I, including one car (alloy head) I serviced for it's entire 900,000km. The biggest risk with a lubricated thread is over tightening. If you use Never Seez and tighten to spec, it's too tight and you are on your way to ruining the thread.
On my FJ for example, I remove the plugs at approx 40,000km. Once cracked, they spin out with my fingers. As long as they are plugs I've fitted, I've never had a problem.

I've been using this product for 40 years. I imagine between Simon and myself we have a sample base of many thousands of spark plugs to draw our conclusion from.



Manufacturers are very cautious when it comes to warnings, as evidenced by the ridiculous labels seen on clothing, toys, appliances, tools etc. and the "Objects in mirror are closer......") message on your car mirrors.

Manufacturers are not giving you advice, they are covering their arse.

Noel

IMO