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Thinking about your issue.... as I do.... you have said in one of your threads you did a cold compression test.... you won't get true readings on a cold engine as everything needs to warm up to correct tolerances. I recommend when you fit new plugs (don't gap them, just fit them out of the box) do a hot compression test.

Dane
 

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Discussion Starter · #42 · (Edited)
Thanks Plumber,
Since you mentioned trying several scopes, any thoughts on this one? Also, I have an iPhone, so I'd only be able to use wireless. When you say it's slower, like how much? Unusable, or just a little on the annoying side, but still gets the job done?

Giddyarp -I'd originally set out to do warm test, but the compression tester from O'Rielly Auto's Loaner Tool program didn't fit, so I had to go back and buy one. [That's a head up for anyone thinking of doing this with a loaner tool.] By then it was too dark and I already had the bike apart. Guess I'll have to do it again. At least I own the right tool this time and I suppose it will be a good time to use the scope. That said what is wrong with keeping these plugs? They only have just over 1000 miles on them? To reiterate from my previous comment it is perfectly OK to gap iridium plugs yourself. IF YOU DO IT PROPERLY.

Also, [for everyone] I've been thinking about the possibility detonation from the carbon build up, but this happens even when cold, and gets better when hot. Glowing carbon embers would be the exact opposite; getting worse when the motor gets hot. That said, as the motor got hot, I actually was able to get the engine to detonate by whacking the throttle really quick from idle; it sound like someone dropped a ball bearing in the cylinder. That was more than likely due to the carbon build up creating glowing embers.

As for the gap on the plugs, usually when you have detonation you retard the spark, not advance it. Making the gap smaller would advance the moment the spark jumps the gap. If the factory manual says .043 is within spec, then what's wrong with using it? Bare in mind those photos are zoomed in a lot and those iridium electrodes are tiny compared to traditional copper, so it looks bigger than it really is since I zoomed in so much. But I will double check them to be safe.
 

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Discussion Starter · #43 · (Edited)
I've got to say I'm feeling much better about the bike today; I had a very productive day.

I started out by meeting fellow forum member bayareaemt, who was good enough to reach out to me and offered to meet so I could listen to his Voyager for comparison. [ Thanks again bayareaemt! ] I brought the stethoscope, and sure enough, his 2012, with only 12k miles, makes the same sound in the same spot. It appears it may just be a normal sound for these bikes. It'd be great if another 1700 owner with a stethoscope could confirm it. Just to be certain.

On the way back from our meeting I got the bike good and hot to preform a hot compression test for more accurate results, but before I even began the test, I noticed the difference in my plugs. They have just over a thousand miles on them, and this is what they looked like a few days ago, after lots of short rides around town. Notice the carbon build up on the base of the electrode:
Automotive tire Gas Water Automotive wheel system Cone

And here is the exact same plug today after my freeway ride:
Hood Automotive tire Grille Automotive lighting Tire


Next were the "hot" compression results. The numbers were closer this time; 79/78 psi front and rear vs. 79/75 cold. I'd planned to do a hot test with oil but I held off so I could use my new borescope. This was the real test since I feared bad scoring from piston slap and significant carbon build up that could be causing detonation. It was a little challenging to get good images but I was able to put my mind at ease.
Front piston:
Window Automotive tire Asphalt Gas Circle

Rear:
Liquid Astronomical object Tints and shades Water Circle

Not nearly as much carbon build up as I'd expected. I'd actually planned to give the pistons a good overnight soak with Seafoam Deep Creep to clean the carbon build up, but after looking at them, I didn't really think they need it. For comparison this is the carbon build up on my 2006 Yamaha Roadstar 1700 with about 10k miles more:
Automotive tire Dishware Cookware and bakeware Rim Serveware

Same piston after cleaning:
Automotive tire Motor vehicle Automotive design Bicycle part Alloy wheel

Next were the cylinder walls. You can see some slight scoring on the front cylinder; it's the darker vertical lines and darker patch on the right:
Cloud Automotive tire Grey Automotive lighting Sky

Then there's this scuff in the rear cylinder, though you can still see the cross hatch machining marks:
Hood Automotive lighting Automotive tire Road surface Asphalt

Lastly were the spark plug gaps; one was a little wide at .045, so I re-gapped them both to .042 just to be on the safe side.

And there you have it. Hopefully someone might find this useful in the future. I know this whole process was hugely helpful for me. Thank you to everyone for all the input.

I will have to keep an eye on the excessive aluminum and fuel in the oil, but I'll that will have to wait until my next oil change for another analysis. Stay tuned.

Cheers all,

VLR20777
 

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Pleased to hear it... Like I said earlier, perhaps you'd feel better about your bike if you invested in a decent set of molded ear-plugs?
 

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Good to see you are getting things figured out. That scope will come in handy in a lot of things. Looks like you need to ride it just a little harder.
These are defiantly noisy motors.
 

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It was great to meet you @VLR20777

As I told you, everything sounded normal to me and whole reason to offer you to listen to my voyager was to remove any doubts you may have had.

Your piston had slightly more carbon than what I saw on mine but I think that much build up is normal. Mine is at 12k miles vs yours is at 27-28k. Even that amount of scoring you see doesn't look out of normal to me. I had tore open my Yamaha Raider at 36k miles and it looked similar to what you are seeing.

Just don't worry about it much and enjoy your ride....
 

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Discussion Starter · #48 ·
I will leave you with some reading homework. I think your engine will be better served when you can eliminate the cause of that 'ping' in the cylinder.
https://www.comeanddriveit.com/engine/detonation-and-knock
Cool cylinder pics! Thanx for sharing and keeping all of us informed. Your co-operation helps others to solve problems BEFORE going to the dealership.
Motomedic, thanks for that excellent link, that's a lot of great info. I'll definitely be studying it closely. I still need to track down my excess fuel issue, it could be contributing to the rough running, but since so many people are running Ivan's ECU Flash without problems what could be contributing to it?
 
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