New Spark Plugs at 8,000mi?

FastRnu2

FastRnu2

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I rode my 2009 FZ1 home from work on Friday. The bike was running normal. Over the weekend I washed it and lubed the chain. Monday morning I filled the tank with 91 octane at the local Chevron by the house and proceeded to work. This is all normal stuff for me.
The bike has a Akro slip on, K&N Filter, & PCIII. No other engine mods. The bike has been running great for the past year.
On the way home from work the bike started running like crap below 3,000RPM. 2-3000RPM is the typical range in stop & go traffic and around town. On the freeway and above 4,000RPM the bike runs perfect.
I did some checking of all the connections under the tank and even disconnected the PCIII. No difference. I filled the tank with Shell 91 octane, no difference. The bike still runs like crap fewer than 3,000RPM which makes it very hard to ride on crowded city streets. It actually drops two cylinders upon take off from a signal until the RPM gets above 3-4,000.
I took it into the local Yamaha Stealer since I have an extended warrantee. They told me that Yamaha’s recommendation for spark plug replacement is at 8,000mi. I have 8,800mi on mine. I approved the spark plug replacement. The bike runs great.
Now my question to all you knowledgeable peeps with the current FI FZ1 is, is this typical for a late model Fuel Injected motorcycle to need a spark plug replacement at 8,000mi? I have had other motorcycles that have had over 20,000mi on the original plugs.
It just doesn’t make sense to me. Should I upgrade the plugs to some unobtainium material?
Any help in this matter would be greatly appreciated. :confused:
 
Did you get to see the old plugs? How worn were they? Maybe you just had a plug go bad before it's time :(

Not sure if the extra expense of Iridium plugs is worth it or not. They may not end up lasting all that much longer than regular copper plugs in our bikes. Their main intent was emissions compliance by car manufactures over 80-100k miles. My Honda Accord calls for 100k plug change intervals. Currently at 80k miles on the original plugs and still runs great!
 
NJFZ1 said:
Did you get to see the old plugs? How worn were they? Maybe you just had a plug go bad before it's time :(

Not sure if the extra expense of Iridium plugs is worth it or not. They may not end up lasting all that much longer than regular copper plugs in our bikes. Their main intent was emissions compliance by car manufactures over 80-100k miles. My Honda Accord calls for 100k plug change intervals. Currently at 80k miles on the original plugs and still runs great!
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+1
I used to change mine more often in my FJR but I'm thinking I leave 'em alone in all my bikes unless a drop in performance such as you had or milage drops off.
Agree you had one go south, first time I have heard of this on a plug with only 8,8k
 
NJFZ1 said:
Did you get to see the old plugs? How worn were they? Maybe you just had a plug go bad before it's time :(
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Yes, they looked worn. I seem to forget something, like your car and my truck, the RPM is considerably less. There's a lot less sparks going on in an engine that cruises at 2500rpm than one that cruises at 5-6000RPM. :gagged:
 
FastRnu2 said:
Yes, they looked worn. I seem to forget something, like your car and my truck, the RPM is considerably less. There's a lot less sparks going on in an engine that cruises at 2500rpm than one that cruises at 5-6000RPM. :gagged:
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Exactly! Your FZ1 is a 1 liter motor pushing out 150hp and revving to 12,000 rpms, so you can expect it to be harder on plugs and to be more sensitive to fouled plugs. Look on the bright side, the FZ only needs the valves checked every 23-24k miles whereas a lot of bikes need the valves adjust as often as 5-10k mile intervals! I'll take a plug change over a valve adjustment any day.
 
My service manual states every 12,500 miles or 20,000 km for spark plug replacement. 8k is premature. Perhaps you should drop to the regular gas as the manual states and stay with 87 octane? That's all I've ever run and I've already got 11k on the bike. :tup:
 
I changed my plugs at 20K and they looked fine and the bike ran fine. I run 87 octane.
 
Good point on the octane! I skimmed right past the part where he mentioned that he is using 91 octane. There is no reason to use anything more than the factory recommended 87 octane!
 
FZ1inNH said:
My service manual states every 12,500 miles or 20,000 km for spark plug replacement. 8k is premature. Perhaps you should drop to the regular gas as the manual states and stay with 87 octane? That's all I've ever run and I've already got 11k on the bike. :tup:
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What year is your bike now? Mine (07) clearly states change at 8,000 miles and that's when I changed mine. I mean comon, unless your riding like me and have over 10K on your bike in less than a year, 8K should be a long time on a bike. However I wouldn't think that the extra 800 mile would have caused that but, if replacing the plugs solved it then we all know, that in the OP's case, his bike needed plugs at exactly 8K. Every bike is different.
 
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gtbigup01 said:
What year is your bike now? Mine (07) clearly states change at 8,000 miles and that's when I changed mine. I mean comon, unless your riding like me and have over 10K on your bike in less than a year, 8K should be a long time on a bike. However I wouldn't think that the extra 800 mile would have caused that but, if replacing the plugs solved it then we all know, that in the OP's case, his bike needed plugs at exactly 8K. Every bike is different.
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Here's a screen capture right out of the 2006 service manual for the FZ1. Mine is a 2009 bike but they haven't changed to date. It clearly states replacing at 20,000 km, right?

attachment.php
 
Spark Plugs

3 months ago I fitted a YEC Plug Set which is Yamahas AIS block off kit [ 5VY-A4890-70]. I removed the cam cover to fit the plugs. My 07 Fazer was at 9,5000Kms. I put new plugs in, it didnt need them but there a big job to replace so I did them. Yamaha manual says clean & regap at 10,000Kms change at 20,000Kms. New plugs give more power and no hassles for along time. I dont use 91octane its crap, we here in New Zealand also have 96 & 98octane. I use 98, dosnt ping with heaps more pull through the gears.
 
FZ1inNH said:
Here's a screen capture right out of the 2006 service manual for the FZ1. Mine is a 2009 bike but they haven't changed to date. It clearly states replacing at 20,000 km, right?

attachment.php
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That's weird. Is that Yamaha service manual or like a Chiltons version for M/C? I will scan a copy of my 07 Owners Manual page that covers all maintenance that states "REPLACE" at 8000 miles.
 
gtbigup01 said:
That's weird. Is that Yamaha service manual or like a Chiltons version for M/C? I will scan a copy of my 07 Owners Manual page that covers all maintenance that states "REPLACE" at 8000 miles.
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That is a cut right out of the service manual from Yamaha for the 2006 model year, not any third-party manual. I wonder if they changed their tune AFTER 2006? So, for grins, I just visited the Yamaha site and got the Owners manual for the 2009 FZ1. Downloaded and yes, it DOES state REPLACE every 8k miles. Hmmmmm.... So then I go to the Yamaha site down under... .AU and download THEIR PDF. There's matches what I posted from the service manual, 12k miles or every 20,000 KM. WTF???
 
FZ1inNH said:
My service manual states every 12,500 miles or 20,000 km for spark plug replacement. 8k is premature. Perhaps you should drop to the regular gas as the manual states and stay with 87 octane? That's all I've ever run and I've already got 11k on the bike. :tup:
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I have always had a problem with premature! :confused0024:

Going forward I think I will change my own plugs. I just couldn't get past the fact that on Friday it ran great and on Monday it ran like crap. I would have sworn it was a sensor failure.

Valve adjustments and fuel grades aside, this bike seems to be a little more temperamental than what I am used to. This is all okay with me since I just love this bike. I just need to adjust my my mental personification to this bike. Wow is this a prolific staement.

Anyway, the bike is good, need the Copperdawg butterflys and Graves Velocity Stacks. Constant upgrades. Cannot get over how great this bike is. :tup:
 
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