Plug Changes

Not even close to the gasoline discussion, but I gotta ask...

Isn't a plug change at 9k miles a bit extreme?

Fuel injection, high voltage ignition...shouldn't they realistically be good for several 10s of thousands of miles?

Even the FJR Manually gives them 20k miles lifespan.

RadioHowie said:

Not even close to the gasoline discussion, but I gotta ask...
Isn't a plug change at 9k miles a bit extreme?

Fuel injection, high voltage ignition...shouldn't they realistically be good for several 10s of thousands of miles?

Even the FJR Manually gives them 20k miles lifespan.

Click to expand...

That's a timely question, since I have 16k on mine right now and have been considering a change... ;-)

RadioHowie said:

Not even close to the gasoline discussion, but I gotta ask...
Isn't a plug change at 9k miles a bit extreme?

Fuel injection, high voltage ignition...shouldn't they realistically be good for several 10s of thousands of miles?

Even the FJR Manually gives them 20k miles lifespan.

Click to expand...

My FJR Manual says 8K. Don't have it in front of me, but I'm almost positive.

FJRTech thinks thats what it says too LINK

schrecke said:

RadioHowie said:

Not even close to the gasoline discussion, but I gotta ask...
Isn't a plug change at 9k miles a bit extreme?

Fuel injection, high voltage ignition...shouldn't they realistically be good for several 10s of thousands of miles?

Even the FJR Manually gives them 20k miles lifespan.

Click to expand...

My FJR Manual says 8K. Don't have it in front of me, but I'm almost positive.

FJRTech thinks thats what it says too LINK

Click to expand...

You are correct. But that does seem a bit excessive, doesn't it? I didn't own mine at 8k, I wonder if the PO replaced them then.

Things that make you go Hmmmm....

Fred W said:

schrecke said:

RadioHowie said:

Not even close to the gasoline discussion, but I gotta ask...
Isn't a plug change at 9k miles a bit extreme?

Fuel injection, high voltage ignition...shouldn't they realistically be good for several 10s of thousands of miles?

Even the FJR Manually gives them 20k miles lifespan.

Click to expand...

My FJR Manual says 8K. Don't have it in front of me, but I'm almost positive.

FJRTech thinks thats what it says too LINK

Click to expand...

You are correct. But that does seem a bit excessive, doesn't it? I didn't own mine at 8k, I wonder if the PO replaced them then.

Things that make you go Hmmmm....

Click to expand...

FWIW mine looked perfect when I removed them at 9K as I stated originally, but you are now at 2x the recommended interval and for the cost ($32 total for Iridiums), and the time (about 30 minutes) its probably something you should do soon. Bonus was that Napa was giving out $10 giftcards with any $25 purchase

RadioHowie said:

Not even close to the gasoline discussion, but I gotta ask...
Isn't a plug change at 9k miles a bit extreme?

Click to expand...

Covered succinctly here before....and many other times...in many other threads.

Thanks for that link Ignacio, that was educational.

Changed mine for the first time at 18K and it was a total waste of money and effort. They were just like brand new, sharp crisp edges to the electrode and all.

S76 said:

They were just like brand new, sharp crisp edges to the electrode and all.

Click to expand...

Wow! From the sharp crisp edges you can tell that the internal resistance is still good and not being hard on other parts of your ignition? You're good!

Screw it, Warchild said "Change 'em" so that's good enough for me!

Well, when ya fuck up, ya fess up. I missed the "km" in the equation...



However, 20,000km isn't even CLOSE to the 8,000 mile change interval being quoted here. More like 12,500 miles.

RadioHowie said:

However, 20,000km isn't even CLOSE to the 8,000 mile change interval being quoted here. More like 12,500 miles.

Click to expand...

We need to see the mathematical conversion chart you used before we can agree with you.

Scab said:

We need to see the mathematical conversion chart

Click to expand...

Check my avatar, it's in there! :huh:

v65 said:

Scab said:

We need to see the mathematical conversion chart

Click to expand...

Check my avatar, it's in there! :huh:

Click to expand...

Oh, shit. Nevermind.

Scab said:

RadioHowie said:

However, 20,000km isn't even CLOSE to the 8,000 mile change interval being quoted here. More like 12,500 miles.

Click to expand...

We need to see the mathematical conversion chart you used before we can agree with you.

Click to expand...

Pain meds still in the system???

"Not even close to the gasoline discussion, but I gotta ask...

Isn't a plug change at 9k miles a bit extreme?

Fuel injection, high voltage ignition...shouldn't they realistically be good for several 10s of thousands of miles?

Even the FJR Manually gives them 20k miles lifespan. "

YES - don't even think about changing them until 20k miles. I changed mine at 9k and they looked and ran like brand new.

Some here are so anal it's unbelievable.

Since not all brands and types of spark plugs are created equal there is no single mileage that covers all plug changes.

Plug changes with leaded fuel were quite common due to lead fouling. Since unleaded fuel became the norm (some of us remember that.....) there is very little to damage spark plugs and they will last a very long time.

As has been stated earlier, the iridium plugs are capable of many tens of thousands of miles running unleaded fuel.

As far as the Yamaha manual recommendations..... there may be more there than just a desire to have the spark plugs serviced frequently. Since the EPA watches the emissions levels of motorcycles these days and the FJR is one of the first ones out there with closed loop fuel control, catalytic converters, etc. it is certified to the lowest of the low emission standards. The EPA checks in service compliance by randomly testing vehicles from the field. If a vehicle should fail, the "manufacturer's service/maintenance schedule" is consulted. Since plugs are on the list it opens the door for a spark plug change and, by default, an inspection by the techs involved at that point, to understand why the system is failing emissions. Without a back door item like a plug change requirement, Yamaha would have no "service" requirements on the emission system and thus no fall back to look into the system if it should fail in an in-service comliance check. Just something to think about with that service requirement in the manual. Not saying that is why it is there...but....could be.....LOL.

RadioHowie said:

Well, when ya fuck up, ya fess up. I missed the "km" in the equation...


However, 20,000km isn't even CLOSE to the 8,000 mile change interval being quoted here. More like 12,500 miles.

Click to expand...

If you read an actual manual from a US model instead of trying to justify your lack of maintenance with some web sourced pdf file, you would see that it does in fact state:

Adjust gap and clean every 4,000 miles

Replace every 8,000 miles (13,000km) or 12 months

If you don't want to do it, don't do it, but don't post inaccurate information that mislead others.

Note: Your picture also states that starting at 50,000km that maintenance cycle repeats....blah blah

Well, thats wrong too. The US manual states, from 24,000 mi (37,000km) or 36 months, the cycle repeats starting from 8,000 mil (13,000km) or 12 months

So I guess you should Fess Up again

Ok Mr jestal, I'll ask this question (and I'm not trying to be a smartass - I'm trying to continue my education!) - I have (because I forgot all about spark plug maint until I read this thread!!) 22.5k miles on my iridium plugs. Haven't cleaned/gapped or done anything to them. Bike runs great as far as I can tell. I just ordered 4 more iridium plugs - when they get here should I put 'em on the shelf, or replace the plugs in the bike?

I know, I know, "it depends on the tactical situation." So.......other than a set period of time to change plugs (preventative maint), what might some symptoms be that would indicate it's time to change plugs (condition based maint)?

Thank you sir.