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Sparkplug Life


priebe

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I disagree but what do I know 😄

 You can also do it when you flush and fill the radiator

 You can just tip the radiator forward it's easy no hoses need be disconnected

having the air injection plumbing gone makes it even easier

 8, 10 to 14000 miles for normal steel core electrode spark plugs is maximum without inspection

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20 hours ago, skipperT said:

@Ride On look fairly decent with good color, your bike must be flashed. 
what does the gap measure?

-Skip

No flash, engine and it's accessories are stock.  I didn't measure the gap, just set them aside - might still have them...

I agree.  Good color (and combustion).  50+ MPG with short windshield and no bags, 40 MPG with 24" Madstad windshield, side and top case. Always 87 octane except 3 tanks prior to storage, then it's gets non-ethonol premium.

Recently finished a 4,300 road trip.  Ran perfect.  27,000 miles on it now. 

20220918_123526.jpg

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  • 6 months later...
On 9/30/2022 at 9:18 AM, 2and3cylinders said:

I disagree but what do I know 😄

 You can also do it when you flush and fill the radiator

 You can just tip the radiator forward it's easy no hoses need be disconnected

having the air injection plumbing gone makes it even easier

 8, 10 to 14000 miles for normal steel core electrode spark plugs is maximum without inspection

 

 Since my CRS is in full bloom - 🙄 - this was the specific spark plug access info I was trying to remember this morning. Thank you, Brett. 

And not to reignite this old spark plug thread - but I am also in the camp that says don't put this off much beyond the Service Interval. Years ago, that interval was 12,000 miles. Nowadays, the Manual calls for 8K interval. So why the change?

I still have contacts within the Yamaha Technical Division in Georgia, and put the question to them last year. They said  that in today's modern engines with high-powered ignition systems, you can't just 'look' at a plug to determine if it's good. The telltale indicator is the amount of internal resistance that has built up in the plug with use.

The reason you change them at 8K is that this is the mileage where they are seeing higher resistance built up. This forces adjacent components (coils, etc) to work that much harder to make the spark plug fire. Sure, you could probably use them beyond that mileage without a lot problems, but replacing them keeps the overall ignition system humming along nicely.  

Mind you, I am just repeating what they told me. 🙃  But they seemed to make a compelling argument. 

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4 hours ago, Warchild said:

... They said  that in today's modern engines with high-powered ignition systems, you can't just 'look' at a plug to determine if it's good. The telltale indicator is the amount of internal resistance that has built up in the plug with use.

The reason you change them at 8K is that this is the mileage where they are seeing higher resistance built up. 

I have heard the term "resistor" spark plug, but never really thought that much about it. The stock plug for Tracer is NGK  CPR9EA-9 and the "R" stands for resistor.

A quick search = resistor to reduce radio interference, which doesn't really matter to me. But the following video by NGK explains that the interference they are blocking also relates to "computer controlled" engine components (ECU).

This is an interesting article by NGK

"Most resistor spark plugs use a monolithic resistor, generally made of graphite and glass materials, to filter the electrical voltage as it passes through the center electrode.

Since resistor type plugs actually “resist” some of the spark energy, non-resistor type plugs actually deliver a more powerful spark. It is for this reason that most racing plugs are non-resistor types. However, in most automotive applications, a resistor plug is required for proper vehicle operation. "

---

My Chevy dealer told me the interval on my Tahoe was 100,000 miles and the original plugs were in there to 110,000 with no noticeable difference when changed.

I never really knew this was a thing, but research finds that spark plug resistors can develop too much resistance and that is something that can be measured. I had no idea.

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1980 Yamaha 850 Triple (sold). Too many bikes to list, FJ-09 is next on my list
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Now I gotta replace my plugs soon!

Gee thanks

But I can do in less than an hour just tipping the rad

Bought another set of stock plugs at PartShark today for $5.50 each, cheapest I found them. Also bought a new set of throttle cables for $34 per Brian's recommendation to ease up effort.  The old set I'll lube again  and keep them as backup but at 58k miles it should help my right wrist. Was going to try the TB cam mod but this will be easier next I have the airbox off.

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