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How good are the br8eg plugs?

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Because mines r going every few rides and I use 32:1 it's an 02 rm 125 I fould bout 3 already . Do they usually go that quick ? I mite need to go back to the oem plugs

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Been using them for years. If your plugs are fouling you are probably jetted too rich.

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Jetting.

Edited by JBFL

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How I fix the jetting? Can I just use less oil ?

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Play with the jets in the carb...

I have never fouled a plug once in my YZ250. I have ridden it for a few years and not once ever had a plug issue. I use the BR8EG. Not the plug.

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How I fix the jetting? Can I just use less oil ?

Do some reading on TT. Hundreds of threads on jetting...

Or type into Google "how to jet a two stroke"....

And buy a manual!

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How I fix the jetting? Can I just use less oil ?

 

 

Spanky's jetting 101:

 
A correctly jetted carb makes a tremendous difference in the torque, midrange pull, top-end pull, and over-rev of your engine. If you have never jetted your bike correctly, you will almost certainly gain some performance at some point in the bike's powerband. 
 
A cleanly jetted pilot circuit can be the difference between having to clutch the bike out of a turn or not. Hard starting when hot or cold, poor response when opening the throttle, reluctance to idle, all of these are symptoms of an improperly sized pilot jet or incorrectly adjusted air screw. 
 
The needle can make all the difference in the world for the power of the machine in most situations, as it controls the throttle range that most riders spend most of their time using. 
 
A correctly sized main jet could mean the difference between being able to rev out high enough to not have to shift one more time at the end of the straight, or the power falling flat on top and requiring you to make that extra shift. 
 
Are you fouling plugs? Many people will tell you all sorts of band-aid fixes, from running less oil, to running a hotter plug. Both are incorrect fixes for plug fouling. It's all in the jetting. An engine that is jetted too rich will have combustion temperatures that are too low to burn the fuel and oil effectively, leading to deposits and wet fouling of the plugs. 
 
Do you have spooge? There are the rare instances where a mechanical issue, such as a leaking wet-side crank seal, can cause spooge. But, by and large, this isn’t the case. In most instances, spooge is caused by rich jetting. It has nothing to do with how much oil you mix in the gas, or how hard you ride. An engine that is jetted too rich will have combustion temperatures that are too low to burn the fuel and oil effectively, resulting in deposits, plug fouling, and spooge. Spooge is nothing more than unburned fuel and oil entering the exhaust. 
 
The only way to know what jetting changes you will need is by trial-and-error. No one can give you jetting specs, because every bike is different, every rider has a different style, and jetting is totally weather dependent. Unless the person telling you what jets to use is riding an identical bike, on the exact same track, at the same time, his recommendations are meaningless. Someone with a good understanding of jettingcan get you in the ball park, but you need to do the testing to determine the correct jetting yourself if you want it right. 
 
Jetting is fairly simple, and is a useful skill to learn if you ride a two-stroke and want it to perform at it's best. 
 
It's very important that you start with the pilot circuit, because the pilot circuit affects the entire throttle range. When you are at full throttle, the main jet is the primary fuel metering device, but the pilot is still delivering fuel as well, adding to the total amount of fuel that your engine is receiving. 
 
Before you start to re-jet your bike, you need a clean air filter, a fresh plug (actually you need several plugs to do plug-chop tests for the main jet), and fresh fuel. 
 
One important detail: Make sure the engine is in good mechanical condition. If your engine has a worn top-end, fix it first. Trying to jet a worn out engine is a waste of time. The same goes for reeds that don't seal properly, and a silencer that needs re-packing. Worn reeds will mimic rich jetting, and worn rings will mimic lean jetting
 
Before you start the jet testing, Install a fresh plug. Set the float level to the proper specs, an incorrect float height will affect yourjetting all across the throttle range. 
 
All jet testing must be done with the engine at full operating temperature. 
 
As already stated, start with the pilot circuit. Turn the air screw all the way in, then turn it out 1.5 turns to start. Start the engine, and turn the idle screw in until you get a slightly fast idle, or hold the throttle just barely cracked, to keep the engine idling. Turn the air screw slowly in, and then out, until you find the point where the idle is fastest. Stop there. Do not open the screw any farther, or your throttle response will be flat and mushy, and the bike may even bog. This is only the starting point, we will still have to tune the air screw for the best response. 
 
Now is the time to determine if you have the correct pilot installed in your carb. The air screw position determines this for you, making it very simple. If your air screw is less than 1 turn from closed, you need a larger pilot jet. If it is more than 2.5 turns from closed, you need a smaller pilot jet. If your engine doesn’t respond to air screw changes, then you either have a dirty carb, or the pilot jet is way too rich. When the pilot jet is way too rich, you are forced to use the idle screw to open the slide so far in order to keep the engine running that the pilot circuit is partially bypassed, and the engine is actually starting to draw fuel through the needle jet. 
 
Once you have determined (and installed it if it's necessary to change it) the correct pilot jet size, and tuned the air screw for the fastest idle, it's time to tune the air screw for the best throttle response. Again, make sure the bike is at full operating temperature. Set the idle back down (the bike should still idle, despite what you read in the Moto Tabloids), and ride the bike, using closed-to-1/4 throttle transitions. Turn the air screw slightly in either direction until you find the point that gives you the best response when cracking the throttle open. Most bikes are sensitive to changes as small as 1/8 of a turn. 
 
The air screw is not a set-it-and-leave-it adjustment. You have to constantly re-adjust the air screw to compensate for changing outdoor temps and humidity. An air screw setting that is perfect in the cool morning air will likely be too rich in the heat of the mid-day. 
 
Now, it's time to work on the needle. Mark the throttle grip at 1/4 and 3/4 openings. Ride the bike between these two marks. If the bike bogs for a second before responding to throttle, lower the clip (raising the needle) a notch at a time until the engine picks up smoothly. If the bike sputters or sounds rough when giving it throttle, raise the clip (lowering the needle) until it runs cleanly. There isn't really any way to test the needle other than by feel, but it's usually quite obvious when it's right or wrong. A too-rich needle can often be felt simply when revving the bike on the stand. The bike will sound rough and raspy when blipping the throttle on the stand. A correctly jetted bike should rev cleanly and crisply. 
 
Last is the main jet. The main jet affects from 1/2 to full throttle. The easiest way to test it is to do a throttle-chop test. With the bike fully warmed up, find a long straight, and install a fresh plug. Start the engine, and do a full-throttle run down the straight, through all gears. As soon as the bike tops out, pull the clutch in, and kill the engine, coasting to a stop. Remove the plug, and look deep down inside the threads, at the base of the insulator. If it is white or gray, the main is too lean. If it is dark brown or black, the main is too rich. The correct color is a medium-dark mocha brown or tan. 
 
Please note that, when reading plugs, the tip of the insulator, threads, etc. are meaningless for jetting purposes. They can tell you a lot of things, but jetting isn’t one of them. Only the mixture ring at the very base of the insulator, inside the threads, can tell you anything about thejetting.
 
 
sparkplug.gif 
 
The slide is also a tuning variable for jetting, affecting the throttle range from 1/8 throttle to approximately 1/3 throttle. If you can’t clean up the small-throttle jetting on your bike no matter how lean you go with the pilot or the needle, the slide is the next step. But few bikes need leaner slides. 
 
Keep in mind, even though this article is intended primarily for two-strokes, four-strokes also need proper jetting to perform right, although they are not quite as fussy as their oil-burning cousins. The only real difference in the two is with the pilot circuit. 
 

Two-strokes have an air screw that you screw in to make the jetting richer, and screw out to make the jetting leaner. Four-strokes, on the other hand, have a fuel adjustment screw that you screw in to make the jetting leaner, and out to make it richer. Their purpose is the same, they just do it in different ways.

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All you probably need to do on your RM 125 is move the clip on the needle 1 notch up, and/or go one step leaner on the pilot.. Moving the clip is free, and a pilot jet costs like $5. Having a hemostat to clamp the throttle cable really makes it easy to move the clip on the needle.  I'm sure there are youtube vids that will show you exactly how to do this, or any experienced 2 stroke guy can show you in 5 minutes or less.

 

Look at the jetting chart in your manual.  I just sold my RM so I can't look at the manual and tell you exactly what to try, but as I recall it has a pretty good jetting chart showing incremental leaner and richer settings.  Leave your premix ratio at 32:1 and fix the jetting.  That will end your plug fouling issues.

 

BTW, you can use BR9ES plugs.  They work fine and can be bought at any autoparts store for $2.  

Edited by rpt50

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BTW, you can use BR9ES plugs.  They work fine and can be bought at any autoparts store for $2.  

Spot on. I don't buy the iridium spark plug hype, just a band aid fix. In my smoker, I run a br7es (which is the specified plug) and spend a whole dollar fifty on each plug, no reason to change to the higher end plug, since the bike runs so well on the bare minimum/base ngk plug.

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BTW, you can use BR9ES plugs. They work fine and can be bought at any autoparts store for $2.

Same here with my 125 after I bought it. Kept fouling plugs after I cleaned the carb the first time and I check the jetting and moved the needle and it still seemed to do it, so instead of a BR9EG, which is the stock plug, I ran a BR8 or 9EG.

Ran outta plugs one weekend before a trailride and Walmart sells Champion sparkplugs and thank god they had one. No where else had one in stock and I needed it.

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You guys really do need to address your jetting however.  It's a good idea to occasionally change the spark plug, but you should not be going through plugs like it sounds you are.  The proper heat range for that bike is a "9".  Use 32:1 and BR9** plugs and adjust your jetting for altitude, temperature and riding conditions/style.  It is really not hard to do at all.  In most cases your "big three" (main jet, clip position, pilot jet) are going to be no more than one step from stock.  

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Spot on. I don't buy the iridium spark plug hype, just a band aid fix. In my smoker, I run a br7es (which is the specified plug) and spend a whole dollar fifty on each plug, no reason to change to the higher end plug, since the bike runs so well on the bare minimum/base ngk plug.

I find that my bike runs crisper and cleaner with fine-wire plugs. The electrodes also last a lot longer than standard plugs, because they produce a more intense spark. I replace my plug when I do a top-end just because I feel a new piston deserves a new plug. If your bike is jetted correctly there's no reason why your plug should need replacing before that.

I buy NGK BR8EIX plugs at my local AutoZone for less than $8, so I'm not sure why people seem to think they're too expensive. If $8 is going to break you then you're in the wrong sport anyway.

Edited by Chokey
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I find that my bike runs crisper and cleaner with fine-wire plugs. The electrodes also last a lot longer than standard plugs, because they produce a more intense spark. I replace my plug when I do a top-end just because I feel a new piston deserves a new plug. If your bike is jetted correctly there's no reason why your plug should need replacing before that.

I buy NGK BR8EIX plugs at my local AutoZone for less than $8, so I'm not sure why people seem to think they're too expensive. If $8 is going to break you then you're in the wrong sport anyway.

Eight bucks doesn't get anywhere near to breaking me, but I figure if the bike runs crisp and clean, there really isn't any reason to throw away extra money. My ride is jetted spot on, so there isn't a concern there. I'll toss in a new plug at the beginning of the year, and they always look coffee brown when I pull them out. What's the saying.... Different strokes for different folks?

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Eight bucks doesn't get anywhere near to breaking me, but I figure if the bike runs crisp and clean, there really isn't any reason to throw away extra money. My ride is jetted spot on, so there isn't a concern there. I'll toss in a new plug at the beginning of the year, and they always look coffee brown when I pull them out. What's the saying.... Different strokes for different folks?

 

 

Ever tried a platinum or iridium plug? I can tell a difference in the way the bike runs. There's more to them than just the precious-metal-electrode. The "X" at the end of the reference number means it uses a "power gap" design. In essence, this is a small gap in the internal conductor that enhances and concentrates the energy from the coil as the electrons pile up at the gap before building up enough energy to leap across it, producing a hotter and more intense spark. The result is fewer misfires (all engines misfire a small percentage of the time, two-strokes are worse than most under light loads).

 

Will standard electrode plugs work? Yep, they work just fine. But if your jetting really is crisp, then you'll probably notice a difference with fine-wire plugs.

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