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Spark plug
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Posted by: my88r

im running a br8es whats the advantage to running the br9es

Posted by: mfr422

my88r,
There is no real advantage to a br9es unless your having detonation problems, it's the same plug just one heat range colder. You may be wanting a br8ev, the ev series uses the smaller electrode sometimes reffered to as a "race" plug. those plugs are what most of the 2 stroke bikes come with. these plugs do foul easier which is why I stick with the good old br8es. Roost on!!

Posted by: my88r

what does the cold plug do and what does the hot plug

Posted by: GPracer2500

Hot plugs vs. cold plug just refers to the ability of the plug to disapate its heat into the head and cooling system. A "hot" plug has a lot of insulation and retains more heat. A "cold" plug has less insulation and can more easily shed its heat.

Spark plugs are designed to operate within specific tempurature ranges. You don't want it too hot or too cold. Only if a plug is overheating would it be appropriate to go to a colder heat range plug. So, lets say you were running a BR8ES and the plug kept failing (melting, cracked/bubbling insulator, etc) because it was overheating (the plug, not the whole engine). That would be a situation where a BR9ES would be appropriate. Plug heat ranges have essentially no impact on engine running temperatures. It's about the tempurature of the plug itself and that's it.

As mentioned, there's no performance advantage per se of one heat range over another. Each engine wants/needs whichever heat range keeps the plug within the correct temp range.

The ground strap of a plug can be examined to help determine if a plug is getting too hot or not hot enough.

Posted by: RichM1983

quote:
Originally posted by GPracer2500
Hot plugs vs. cold plug just refers to the ability of the plug to disapate its heat into the head and cooling system. A "hot" plug has a lot of insulation and retains more heat. A "cold" plug has less insulation and can more easily shed its heat.

Spark plugs are designed to operate within specific tempurature ranges. You don't want it too hot or too cold. Only if a plug is overheating would it be appropriate to go to a colder heat range plug. So, lets say you were running a BR8ES and the plug kept failing (melting, cracked/bubbling insulator, etc) because it was overheating (the plug, not the whole engine). That would be a situation where a BR9ES would be appropriate. Plug heat ranges have essentially no impact on engine running temperatures. It's about the tempurature of the plug itself and that's it.

As mentioned, there's no performance advantage per se of one heat range over another. Each engine wants/needs whichever heat range keeps the plug within the correct temp range.

The ground strap of a plug can be examined to help determine if a plug is getting too hot or not hot enough.

Wow you learn something new everyday. I thought the different heat were referring to the intensity of the spark. Like a hotter plug made a bigger spark.

Posted by: louis

I use a br8eya it has a split electrode I have never had a problem running them. (its the same plug I use in my sled)

Posted by: my88r

is it a more expensive plug

Posted by: HondaATC500X

Following up with what GPracer said, I've found that you can also use different heat ranges on the plugs as a band aid for jetting sometimes. If its running richer then heck, drop an 8 or maybe even a 7 in. If its kinda pingy and lean run a 9 or maybe a 10. Sometimes I can get my R running pretty good with a different heat range plug if my carb happens to be off a bit one direction or the other.

Others will probably disagree but I've also found better piston life if you run a colder plug with leaner jetting then if you run a hotter plug with richer jetting. Thats .02

Posted by: wilkin250r

GPracer gave a good explanation of WHAT the heat range does, but he didn't say WHY.

The obvious: you are burning fuel and oil, which will leave deposits on the plug. The deposits can build up and cause the plug to foul.

The solution: The plug is designed to keep itself clean by being hot enough to burn off deposits. The heat comes from the burning fuel, combustion. But if it's too hot, it causes problems like detonation. Too cold, and it doesn't burn off deposits.

But different engines and different running conditions will give different amounts of heat to the plug. So how do you keep it at just the right temperature range? It's built into the plug. Different electrode configurations will keep or get rid of different amounts of heat, and that's the difference in the "heat range" of the plug.

For example, if an engine doesn't give a whole lot of heat to the plug, the plug needs to keep all the heat in itself in order to remain hot enough to burn off deposits. This is a "hot" plug, because it doesn't get rid of much of it's heat. If you put in a cold plug in this situation, the electrode would get rid of all of it's heat, it would run too cold and eventually foul because of deposit buildup.

The reverse is also true. If an engine gives a lot of heat to the plug, you need a "cold" plug, (gets rid of heat quickly) to keep the plug from overheating.

Keep in mind that a "lot of heat" still isn't a large amount. Yes, it makes a huge difference to the temperature of the plug, but it doesn't make any difference to the actual engine temp. A "colder" plug gets rid of more heat in itself, but it makes almost no difference at all to engine temps, like maybe 1/100 of a degree. A "cold" plug will not fix an overheating engine by pulling more heat away.

Posted by: my88r

thanks for clearing that up for me

Posted by: kiesta00

Some questions:

1) Why did honda go from a b8es in 86, b9es in 87-88, and b7es in 89?

2) Is there really a difference in performance when using standard "S" plugs vs "IX" iridium vs "G" racing plugs?

Posted by: wilkin250r

I'll admit, I haven't been as diligent in my research, but I haven't heard of the "G" plug for the 250r.

I like the IX Iridium plugs. I don't know if they make a real-world difference, but the theory is solid, it's not just a marketing gimmick. There is a substantial difference in the electric field surrounding a sharp point (like the Iridium plugs) and a rounded point (like an ordinary plug). A sharp point creates a much stronger electric field, which should allow the spark to jump the gap easier, and do it under worse conditions (high compression, partially fouled, ect ect).

Manufacturer's will claim better gas milage, more power, and riches and glory from their spark plugs. It's all BS. But you CAN make a plug that fires easier, so it will work better in less-than-ideal conditions. Not more power, but more reliability. Based on my knowledge of electricity, I honestly believe the iridium plugs do it.

Posted by: kiesta00

Makes sense, I knew I would use that emag stuff somewhere lol