View Full Version : Spark Plugs

4th June 2006, 18:53
I have just gone for a ride and my bike started running funny...
Sounded 'fluttery' around 5-6000 rpm and when riding at 100kph it kinda went faster and slower at constant revs...
My mate thought it could be running on three cylinders and suggested i check the spark plugs.
I ripped the spark plugs out of my bike (as an aside my efforts in attempting to remove the damn things showed that having good tools makes a job much easier - I spent around an hour trying to get the plugs out with crap tools... went down to repco and got a motorbike plug tool for $4... didnt work. Went back and got a set of deep sockets by powerbuilt and bam the plugs just fell out.) and here are some pictures of them.

The third one from the left is whiter than the others...
what does this mean?

4th June 2006, 19:00
I have experienced a similar if not the same problem with my bike, the solution was purchasing new spark plugs. The cause of my problem was a tired spark plug plus the clearance measurement had decreased.

Apparently they are suppose to be replaced every 8,000km so when this happened to me it was bang on 8,000km since they were last replaced.

Once changed, I also noticed an increase in power and fuel mileage increased marginally.

4th June 2006, 19:07
The second from the right seems to be running leaner than the third from the left to me.....

4th June 2006, 19:23
'One of these things is not like the others...'. Your plugs should last well past 8000kms. Hell even my plug chewing RZ500 could use a set of plugs longer than that.

4th June 2006, 20:06
Yeah my plan at the moment is to go get some new plugs tomorrow and see what that does... I actually have no idea how long since the plugs were replaced. All i know is that i havnt replaced them since i got the bike 6 months ago.

Yeah i did notice something funny about the second from the right plug as well... Thanks motu for the help

4th June 2006, 20:14
re that grey plug check for an air leak or partly blocked jet

4th June 2006, 20:35
would of thought you're get more out of the spark plugs, i would be leaning towards the carbs.