Do my sparkplugs need replacing?

[rustyrobot]

I have probably had my bike for about 3000kms now. I have no idea when the plugs were last changed but I certainly haven't done it. When I took the plugs out they were covered in quite a lot of wet oil residue. I wiped that off, and this is the way the plugs look underneath. They seem OK to me, but I don't really know. I looked at some websites (like this one (http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/faqread.asp?mode=nml)) but couldn't really tell whether my plugs were on the fine side of normal or the 'replace' side.

220698220699

[Jonno.]

How old's the bike?

The most important question is how much is a new set? Change them if you can afford it and be thankful you don't have a VFR with plugs that cost $40 each :crybaby:

[rustyrobot]

Bike is 22 years old. Plugs cost about $20 each, so thankfully cheaper than yours. Guess I'll just get a new set then.

[SMOKEU]

Bike is 22 years old. Plugs cost about $20 each, so thankfully cheaper than yours. Guess I'll just get a new set then.

Are those CR8/CR9 plugs?

[rustyrobot]

Yep, CR9. Going by price on Trademe.

[cbfb]

They don't look all that bad, bit of carbon fouling round the outsides. Mine are worse but then I've spent enough on the overhaul already so they can wait.

Give them a clean with brake cleaner and a bit of a scrub with a wire brush, blow out any crud with compressed air, check the gap then chuck them back in.

You can sandblast them too apparently but not recommending it coz I've never done it personally.

Also if they are carbon fouling changing to a hotter plug might help.

Now the oil is a bit of a concern, might want to get that checked out. Mine is doing it on one cylinder but not figured out why yet.

[rustyrobot]

Don't have any brake cleaner but got a can of degreaser. Will that be an ok substitute?

[cbfb]

Dunno to be honest, I've always used brake cleaner. Doubt it would do any harm so long as you dry it off after, but don't think it would do much to the carbon fouling like the brake cleaner does. The zuki shop manual for my Bandit says to use a pointed tool to carefully scrape the crap off.

[SMOKEU]

Yep, CR9. Going by price on Trademe.

I've got the same ones on my CBR. Try Super Cheap Colombo St, they're often a bit cheaper than the rest.

[rustyrobot]

I've got the same ones on my CBR. Try Super Cheap Colombo St, they're often a bit cheaper than the rest.

Cool, will check out Super Cheap, but I'm not riding down to Christchurch to do it, I'll just try the one round the corner. :)

[SMOKEU]

Cool, will check out Super Cheap, but I'm not riding down to Christchurch to do it, I'll just try the one round the corner. :)

Sorry, my bad. I thought you were in Christchurch.

[porky]

Not even run in.

Plugs will tell you what was happening prior to shutting the motor down. Looks like a bit of tootling around.
a couple of questions. The oil was around the electrode? or on the thread. Was it oil? Oil in the pot would have it running like a two stroke (blue exhaust smoke) unless its only a small amount and synthetic.
As said clean them, warm bike up, take it for a good ride, dont tootle, kill the bike, pull the plugs

[rustyrobot]

Not even run in.

Plugs will tell you what was happening prior to shutting the motor down. Looks like a bit of tootling around.
a couple of questions. The oil was around the electrode? or on the thread. Was it oil? Oil in the pot would have it running like a two stroke (blue exhaust smoke) unless its only a small amount and synthetic.
As said clean them, warm bike up, take it for a good ride, dont tootle, kill the bike, pull the plugs

It was oil on the thread, and when I say oil, I mean a black oil-like substance. Not a huge amount, but was still unexpected.

[porky]

It was oil on the thread, and when I say oil, I mean a black oil-like substance. Not a huge amount, but was still unexpected.

My take on the situation for what its worth. Oil on the threads was put there, black around electrode is standard carbon deposits, plugs arnt wet so sparks good. Clean plugs , take her for a blast, kill the beast and pull the plugs. (dont let it idle to much before shutting it down) Get ya magic chart out and compare. Should be a nice clean burn.

[imdying]

If the bike ran ok, put them back in.

[klyong82]

I've got the same ones on my CBR. Try Super Cheap Colombo St, they're often a bit cheaper than the rest.

I thought the CBR250 uses CR8EH-9 or CR9EH-9 spark plugs....:blink:

[SMOKEU]

I thought the CBR250 uses CR8EH-9 or CR9EH-9 spark plugs....:blink:

I'm running different plugs in mine than what it came standard with, under the advice from some of the cbr250.com people. My bike has never run better since I've put those plugs in.

[robo555]

I've got the same ones on my CBR. Try Super Cheap Colombo St, they're often a bit cheaper than the rest.

You're talking about the one near Sydenham, instead of Super Cheap Autos right?

What do you think of the prices at that store? I went there once just for a look, and from memory the prices on the shelf were rediculous, double digit for a can of CRC or WD-40.

[SMOKEU]

You're talking about the one near Sydenham, instead of Super Cheap Autos right?

What do you think of the prices at that store? I went there once just for a look, and from memory the prices on the shelf were rediculous, double digit for a can of CRC or WD-40.

I'm talking about the one on Colombo St, opposite the Funky Pumpkin and bogan Mobil. I have found prices there are generally cheaper than Ripco and the other Super Cheap Autos, but it pays to shop around.