fouling plugs

[Tyler125]

I just rode my Cr125 today. Rebult top end and runs great! Only problem I have is that it was fouling the plugs I have in about an hour. I was riding and it was real strong and then I lost all low end power. Couldnt make it up a hill for anything, bogged real bad. But once we put in a new spark plug I got up the hill and it rode very strong, but didnt ride it enough to foul the other plug.

What gap should they be set at? Also I was running NGK R plugs, anything else I should try for my bike?

 

[IndyMX]

You're jetting is probably way too rich.

 

[Tyler125]

So I dont necessarily need hotter or colder plugs?


The jetting stuff confuses me, I havent been into dirt bikes long.

 

[IndyMX]

read as much as you can about jetting.. It's really not as hard as it seems.

 

[Tyler125]

I am. The reason I thought it could be plugs is because I used the same plug my buddy used in his KX250.

 

[Cman250]

So I dont necessarily need hotter or colder plugs?


The jetting stuff confuses me, I havent been into dirt bikes long.

Nah not unless your running a plug that is way out of the range. I run a BR8ES on my CR250 so you would probably want to run one class hotter than mine. You might want to invest in a manual on your bike it will make sure your running in sync with your recomended specs.

 

[flyingfuzzball]

Nah not unless your running a plug that is way out of the range. I run a BR8ES on my CR250 so you would probably want to run one class hotter than mine. You might want to invest in a manual on your bike it will make sure your running in sync with your recomended specs.

most people run a br9es. an 8 is good for trail riding but for MX it is too hot.

 

[Tyler125]

Yea, manual getting ordered tomorrow. I was just hoping it could be the plug. I may try one class hotter to see if that works.

 

[Tyler125]

The plugs I bought are BPR6ES. I think it maybe the plugs this time. Im gonna try 8's and see how it runs! Didnt realise what they were.

 

[IndyMX]

The plugs I bought are BPR6ES. I think it maybe the plugs this time. Im gonna try 8's and see how it runs! Didnt realise what they were.

You should be running a BR9 or BR10 in that bike.. BR6??? Holy crap.. that's quite the hot plug.

Remember the lower the number the hotter the plug.

Bogging is not caused by the plug, it's caused by improper jetting.

What's going on with your buddy's bike has nothing to do with yours.

Learn to jet, and you'll see what I mean.

 

[Tyler125]

Why cant the boggin be caused by the plug? If it is way too hot and it is fouling badly and quickly why cant tha cause it? It doesnt bogg at lower rpm with the fresh plug even though it was too hot. Once it fouled, it had no low end power. It runs near perfect with the fresh plug.

 

[IndyMX]

All bikes will run great with a fresh plug.

Whatever you say, chase that bog with plugs if you want. But until you learn to jet properly, you're gonna spend a small fortune on them.

Once you understand what heat range in a plug is, and why jetting is the critical component, you will know exactly why it's not the plug that's causing it.

I suggest you use the search function on here, look for jetting, plug reading, and anything on the subject of performance by Rich or Eric and do some reading.

 

[IndyMX]

http://www.dirtrider.net/forums3/showthread.php?t=42618

 

[Tyler125]

I will. I wasnt being cocky just trying to understand it.