How does this plug look to you

When u get a new plug, the cap is white, that's what i'm referring to.

And so is mine after 30 hours. Where do you see black/sooty? :D

4Takt

no i was talking about Max Power's plug he posted being black an Sooty.... Ur's is pretty good, maybe alitle lean but not bad at all. That clear things up?

Yes, thanks.

i mean i use to have a bike that fouled plugs everyday, and it was shiny black oil, so i know that very well, U could probably richin ur mixture just alittle, but the cap isn't white, it's a tanish brown so thats ok.

There is a great jetting guide HERE

The only difference is that for sea level they recommend a 175 main. Given that the base ring is black and the rest of the plug is very white, I will stick with the plug is too hot. Let us know what the plug number is in the am.

i mean i use to have a bike that fouled plugs everyday, and it was shiny black oil, so i know that very well, U could probably richin ur mixture just alittle, but the cap isn't white, it's a tanish brown so thats ok.

What bike?

it was a rm 125, i finally got it fixed, there was a seal that was bad, and it fixed it after we found that..

to make u feel better or more comfortable, just richen your mixture alittle bit Dtakt.

There is a great jetting guide HERE

The only difference is that for sea level they recommend a 175 main. Given that the base ring is black and the rest of the plug is very white, I will stick with the plug is too hot. Let us know what the plug number is in the am.

That's the guide I followed. At sea level from 90-100F (I'm in south Louisiana) they recommend the #168 jet. Look at the whole chart incl. temperature.

I tried a 175 first and it was too rich.

I may try a 172, or maybe first raise the needle a notch with the 168.

4Takt

And to test the spark plug for the throttle opening you want. Just take ur bike out for a spin, and hold it at the throttle position you want to test for about a mile, then cut the engine and let it coast to a stop. Check the plug, then adjust as needed, needle, jet's....etc...depending on where u need improvements in ur powerband...

So essentially the jet size gets you roughly in the ballpark, and then the needle position is for fine tuning in between jet sizes, correct?

4Takt

That's the guide I followed. At sea level from 90-100F (I'm in south Louisiana) they recommend the #168 jet. Look at the whole chart incl. temperature.

I tried a 175 first and it was too rich.

I may try a 172, or maybe first raise the needle a notch with the 168.

4Takt

First off... Welcome to the club.

16755372-L.jpg

These bikes are very fun.

Let us know what plug is in your bike tomorrow.

Needle position?

<thread hijack>

Right up next to your avatar! ;-)

</thread hijack>

Carry on.

<thread hijack>

Right up next to your avatar! ;-)

</thread hijack>

Carry on.

Keep your hands where I can see them.

it was a rm 125, i finally got it fixed, there was a seal that was bad, and it fixed it after we found that..

I owned it's big brother. :D

12514641-L.jpg

Looks a bit lean to me......... :D

First off... Welcome to the club.

Let us know what plug is in your bike tomorrow.

Thanks, Max Power.

My first four stroke in 20 years, I had an XR600R in the early eighties.

This bike is a lot of fun. My other ride is an '83 Maico MC490, which is of

course that much more fun. I'll never get over the big two strokes...

Anyway, the plug in my XR is an NGK BKR7E.

4Takt

And to test the spark plug for the throttle opening you want. Just take ur bike out for a spin, and hold it at the throttle position you want to test for about a mile, then cut the engine and let it coast to a stop. Check the plug, then adjust as needed, needle, jet's....etc...depending on where u need improvements in ur powerband...

This is so important. If you rode the bike around, idled into the garage and then pulled the plug, you will have a 'muddled' mixture of colors from the various fuel/air mixtures found at different rpms. Remember that with a carburetor, there are only a few fixed points in the rpm range that are adjustable, it varies between richer and leaner as the rpm transitions through carb's three basic metering levels. Top end (WOT): main jet. Idle: pilot/slow jet and idle-mixture screw. And mid throttle, which is the combination of all of the above, but mainly needle size and clip position. As you transition through these mixture ranges, the plug color will change gradually, which is why it is necessary to use a new or shot-cleaned plug to check for color every time. It really takes quite a while to burn off old deposits and leave new ones from the current rpm range. Usually guys will check the plug at WOT only, then adjust the other pieces for best rideability, as damage is only likely to occur at extended high rpm usage. Hope this makes sense, it is my best understanding of the practice of plug reading.

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