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fouling plugs on my 04 cr125

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im fouling plugs on my cr125 when i start it up for the first time and when i ride slow singletrack

live in phoenix not sure if it is the jetting or oil gas mixture i run 32:1

what sparkplug should i use

thanks

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I had the same problem with my son´s CR125R 04

The problem usally is the riding style, if not, then jetting to leaner should be a cure.

I handled the problem with using 1 level hotter spark plug.

Now his skill is better and fouling a plug is not a problem.

Rewing it up occasonally will also burn of the residue on the spark plug.

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what kind of plugs are you using

what do you mix the gas and oil i mix at 32:1

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My 04 had the same problem just leaned up the main jet and never fouled a plug sense. also that was only when i was breaking it in and had stock jetting.

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I had the same problem with my son´s CR125R 04

The problem usally is the riding style, if not, then jetting to leaner should be a cure.

I handled the problem with using 1 level hotter spark plug.

Now his skill is better and fouling a plug is not a problem.

Rewing it up occasonally will also burn of the residue on the spark plug.

Can using a hotter plug cause any long term engine damage?

My son's 2003 CR85 fouled a plug for the first time the other day at the track. Not knowing the symptoms of a fouled plug, I was at a loss. I was lucky enough to have a veteran 2 stroke owner parked next to me and he was kind enough to help us troubleshoot the problem. I didn't have any extra plugs but he gave us an old one he had and it worked. But, it was an 8...the owners manual calls for a 10. he said it should be fine temprarily, as long as he took frequent breaks to let it cool down...which we did. It did run like a raped ape with that hotter plug. My only worry after the fact, was if I caused any damage.

What would cause a bike to suddenly start fouling plugs out of nowhere like DPR_92 and I are experiencing????

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I can't think of a single reason why a hotter plug would make it "run like a raped ape". Might want to google up spark plug heat range and get a better understanding of how a spark plug works. Tdub

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"What would cause a bike to suddenly start fouling plugs out of nowhere like DPR_92 and I are experiencing????"

Possibly a drop in compression from lack of timely maintenance. Over oiled air cleaner? The Plug could just be close to it's service life........

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I wouldn't put a hotter plug in my CR250 if someone held a gun to my head...if you're using at least highest octane pump gas and a quality premix oil, you do not have to run 32:1 ratio...I've run 50:1 with 93 Amoco/BP pump gas and Yamalube 2R with NGK plug for the last 8 years without 'nary a problem...not even a fouled plug. And it runs best with the NGK BR8ES plug, which is the least expensive of the three that are spec'ed for this bike. Only jetting changes have been moving the needle clip to the center position.

This bike does have a PC pipe and shorty silencer w/Boyesen reeds and I ride at 1,000-3,000ft. elevation.

One last thing...always have a clean(and like TDub said; not over-oiled) air filter, I'm dilegent about having my exhaust valve clean and working properly, as this model will stick with relative ease; and NEVER run cheap OTC spark plugs (aka Autolite, etc)

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I can't think of a single reason why a hotter plug would make it "run like a raped ape". Might want to google up spark plug heat range and get a better understanding of how a spark plug works. Tdub

It could have been my imagination.....but it did feel more repsonsive. Maybe the hotter plug was helping the bike burn more efficiently :ride: ? It could have been my imagination, but it seemed like less smoke too......I don't know. In any case...., I'm getting a couple new plugs and considering doing the top end.

My son doesn't get on the pipe too often, so maybe that caused it to foul over time. We maintain it meticulously...so I doubt it's in that department.

Thanks for the advice :thumbsup: .

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If your bike is spec'ed out for the BR8, run the 8. It's a hotter plug than the 9, but not as hot as a 7....run the plug that Mr. Honda says to run, at the gap he says to set, and at least you'll have eliminated that possible cause. If not the problem itself.

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