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HOW TO: Tips on replacing your Spark Plugs

Spyder Eye

Spyder Eye

New member
So I needed to replace my spark plugs and I thought I would document how I did it for those of you that are interested.

First drop your radiator. A side note, I have to unplug my radiator fan power cables to create some extra slack so I can move the radiator away from the engine head.





I generally work with one spark plug at a time. First, unclip the coil connector from the plug you want to work on. The coil should come out with a little effort. I just twisted back and forth while pulling up and it eventually pulled free without any drama.

Now you will need a spark plug socket and a 3 or 4 inch extension. Anything too much longer than that you might end up hitting the frame when you try to get your ratchet in there.

My spark plugs were torqued correctly from factory because it required little to no effect to break them loose. Pulling them out is another story because my spark plug socket no longer holds spark plugs like it used to. So I used one these to pull them out because the hole is fairly deep. Side note, Arnold showed me how to use this thing back in the day.





You should be left with this after pulling out the plug:





At this point you should check the gap on your new spark plugs. Also, when putting in the new spark plugs NGK doesn't require any anti-seize. When installing new plugs I usually use a piece of plastic tubing and put it on the end of the plug. This allows me to guide the plug into place, as well as, get it hand tight without the risk of it cross threading. Once it's in there just pull off the tubing and torque to spec.











Rinse and repeat with the rest of them. Hope someone finds this useful. Thanks.


Here is a pic of the old bunch:

 
Fazed said:
I would always check the gap of spark plugs before installing, regardless of what the packet has written on them.
Click to expand...

Yep, I agree. I'll bet 90% of the plugs I have installed over the years have come out of the box within a pube or two of being spot on. But I have also had a few that were closed or wide apart.
 
Thanks for the write up. I'm curious as to why you changed your plugs. They look to be in great shape to me. How many km/miles do you have on them?
 
I do mine every 10000kms or there abouts. I figure that you have to check them anyway and as it is a pain in the backside to get to them, throwing in a new set at $10 isn't going to break the bank.
 
I'd recommend after removing the coil, to use some compressed air to blow any crap out of the area before removing the plug. Also If you happen to have the plug socket that fits a WR450 (Hinged in the middle thing) its good for removing and installing these also. You can use a 14mm ratchet ring on the top.
 
The following may be helpful to those wanting to change spark plugs. I've just been checking my Owner's Manual and find
1) spark plug change interval is 20,000 Km or 12,000 miles
2) standard plug is listed as NGK CR9E
3) to extend the change interval (as well as giving a claimed better burn in the combustion chamber) one could change the plug to the new Iridium type plug. These have central electrode (no gap to worry about) and, for cars, the change interval is extended to 100,000 Km or 60,000 miles.
4) Iridium plugs cost around AUD$20 which would equate to something like USD$19.00

I'm planning on changing to the Iridium plugs at the 12,000 mile service.

Hope this info is helpful.
 
Last edited:
Bolstie said:
The following may be helpful to those wanting to change spark plugs. I've just been checking my Owner's Manual and find
1) spark plug change interval is 20,000 Km or 12,000 miles
2) standard plug is listed as NGK CR9E
3) to extend the change interval (as well as giving a claimed better burn in the combustion chamber) one could change the plug to the new Iridium type plug. These have central electrode (no gap to worry about) and, for cars, the change interval is extended to 100,000 Km or 60,000 miles.
4) Iridium plugs cost around AUD$20 which would equate to something like USD$19.00

I'm planning on changing to the Iridium plugs at the 12,000 mile service.

Hope this info is helpful.
Click to expand...

My manual says 8,000m (13,000km)
Got the iridium plugs for $26.99 from eBay. Free shipping
 
I have been running the iradinium for 2k miles. Along with a shorai lfx lithium ion battery..she fires right up now! (Was having starting issues around 10k...didn't realize need plugs at 8 k)
 
top write up and as ive never changed a plug before i feel after reading this it would be a doddle! i'm only at 5500 ish miles so a while to go yet but all in the brain storage now :) cheers
 
great post

i just replaced my plugs and want to say thanks for the post. I was a little late in replacing them as my bike has 13,600 miles but did it with no problems in a little over an hour with the guide. It was idling a little rough before and now runs like brand new. thanks again!
 
Thank you for posing this, one question about putting the coils back in. i cant seem to get them to be flush like they were when i pulled them out. any tips? flush i mean the rubber gasket at the top of the coil with the engine.
 
Press down as hard as you can while turning back and forth. It will eventually seat. Mine where a pain to. If you just said to yourself "I tried that" well try again brother. To be honest that was the biggest struggle I had.
 
I always use dielectric grease on both the seal around the spark plug an the one on the bottom of the coil. It helps seal the rubber, give the rubber a bit of lube to help it slip on the spark plug and is meant for electrical connections.
 
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