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Is there a hotter plug I can run for my 02 300exc then the BR8ECM 

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Why do you want a hotter plug? Your plug photos look a little rich, or maybe a bit oil stained. NGK plugs get hotter when the number is smaller. But don't do that unless you have good reason. On a stock motor, run the heat range specified by KTM

Read the NGK article on heat ranges:
https://www.ngk.com/product.aspx?zpid=9542

 

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If that's what it looks like right out of the engine without wiping it off or cleaning it, I say it looks good.

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Sorry I had to post the picture here because I couldn't send it to someone through messages

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If that's what it looks like right out of the engine without wiping it off or cleaning it, I say it looks good.

I did wipe the treads. That was a brand new plug 3 rides ago stock jetting is 45/175 I'm running 42/165 thinking about going down to a 40/160

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Why do you want a hotter plug? Your plug photos look a little rich, or maybe a bit oil stained. NGK plugs get hotter when the number is smaller. But don't do that unless you have good reason. On a stock motor, run the heat range specified by KTM
Read the NGK article on heat ranges:
https://www.ngk.com/product.aspx?zpid=9542
 

I wanna run a hotter plug due to the trails here being so tight and technical I cant really be on the pipe so much.

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8 minutes ago, nopo530 said:

I wanna run a hotter plug due to the trails here being so tight and technical I cant really be on the pipe so much.

That is not a good reason. I would not make the change.

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4 hours ago, pat22043 said:

That is not a good reason. I would not make the change.

I agree, tight and technical usually causes less efficient engine cooling. A hotter plug would exacerbate that. You'd probably see the engine/cooling system overheat more often. Work on jetting instead. If it's so rich that you're loading up in the technical stuff, there's room to lean it out.

What's your elevation?

For slow, tight and technical riding, you don't need to be changing the main jet. A lot of that type ridings throttle is just off idle. The pilot/needle transition. Work on those

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Sea level to about 4000ft 70-110f I'm already 10 off from stock main and 3 off from pilot. I just wasn't sure how far I could push it I'm gonna run the 8 plug and lean the jets out and I'll see where that gets me.

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Are you checking the tuning of or retuning the air screw when you change elevation and temperature? It's not a set and forget item. Use the "whack the throttle" method.

Edited by Trailryder42

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You have to get the mixture right first.

Don't trust only the ceramic, which is inspected for mixture down near the shell where we cannot see and typically the plug needs to be cut apart to really be seen.

plugchops-2.jpg 

Look up "PLUG CHOP" for the process.

The metal ring at the top of the threads is also a guide to mixture and plug temp. I like this graphic:

image002.jpg

Too hot a plug can mean a burnt piston the first time you jump on the throttle. 

Edited by sbest
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See @sbest's image, once you get the jetting close, the only things you are about are the "jetting read base" and "preignition/detonation" areas. Which are way down inside the plug.

Don't even bother to look way out by the gap

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Are you checking the tuning of or retuning the air screw when you change elevation and temperature? It's not a set and forget item. Use the "whack the throttle" method.

As in do I mess with the air screw as I ride up the mountain? Or when it's hotter or cooler out? No i don't mess with it one I've set it. I only mess with air screw/jetting summer/winter.

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You have to get the mixture right first.
Don't trust only the ceramic, which is inspected for mixture down near the shell where we cannot see and typically the plug needs to be cut apart to really be seen.
plugchops-2.jpg 
Look up "PLUG CHOP" for the process.
The metal ring at the top of the threads is also a guide to mixture and plug temp. I like this graphic:
image002.jpg
Too hot a plug can mean a burnt piston the first time you jump on the throttle. 

Very informative thank you. After talking with a guy on here about 2stroke oils the first thing I'm gonna try is switch oils. I'm using motul 800 which I guess has a real high flash point and intended for high revving hot engines like that of a 125/250 mx bike. I will be switching to something that has a lower flash point and better suited for 2 stroke trail bike any ideas?
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1 hour ago, nopo530 said:


As in do I mess with the air screw as I ride up the mountain? Or when it's hotter or cooler out? No i don't mess with it one I've set it. I only mess with air screw/jetting summer/winter.

You should check it/retune it every time you change elevation, as well as drastic weather changes.

I agree with switching to a lower flash point oil. The Motul 800 is too high. You can stay with the Motul but use the 710. I've used it in my 300 since new.

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Quick question I just found some torco gp-7 synthetic it must be back when I had a rm 125. it's gotta be 4-5 years old is it still good? I just looked it up and it has a very low flash point of 74c.IMG_1492548714.181985.jpg

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