2004 YZ250 Spark plug Issues

Hi everyone!!:rant: I fouled the plug on my bike today, so I took it out and installed another one... But the plug that was in the bike, is a NGK BR8EG(the one mentioned in the manual), but the new plug that I put in is a NGK B9ES... My question is, Is this plug alright for my bike? Or can it damage the motor? Any help will be appreciated!! Thanks!!:ride::thumbsup:

Your new plug is one step colder. It will not hurt anything. It may be best to get some of the BR8Es's plugs (cheaper than the "EG") and jet your bike so that this does not happen again.

I thought that when the number went up it got hotter. Good info for the future or I would of bought a bunch of cold plugs.

I thought that when the number went up it got hotter. Good info for the future or I would of bought a bunch of cold plugs.

NGK has a funny labeling system. The lower the number, the hotter the plug.

If you buy a champion or many of the other brands the higher numbers are hotter.

Ok, thanks for the help RC Cannon!:rant::thumbsup: It fouled because it was still on it's first tank since the rebuild(so it's a little rich).... :ride:

I got one last thing to ask about... I went to buy some new spark plugs, and got some BR8ES's... But I would like to know, what is the difference between the B8ES and the BR8ES?? Also what is the difference with the BR8EG? Thanks alot!!:rant::thumbsup::ride:

The "R" stands for resistor. This is built in the spark plug. Some say it can cause interference to not use the "R" series , but I have never had a problem.

The "EG" is supposed to be a slightly higher grade plug with respect to the electrode. Not quite a "fine wire" or high end plug, but better...according to NGK.

I have found the "EG's" to foul much easier than the plain "ES" at 1/2 the cost. I dont buy eg's anymore unless I get a really good deal. NGK also has an "EiX" series which is a fine wire plug. I found a few of these for 25 cents (list is 10.00) and have been using them. No real difference in the way th ebike runs. I dont see myself paying list for them.

Great!:ride: Thanks for the info:) I suppose that I'll be fine with the BR8ES....:thumbsup:

plugs are dirt cheap if you go to advanced auto parts and they come in next day.

I have found the "EG's" to foul much easier than the plain "ES" at 1/2 the cost.

i agree with this statement.:thumbsup:

I have found the "EG's" to foul much easier than the plain "ES" at 1/2 the cost.

i agree with this statement.:thumbsup:

I wonder what the deal is with the eg's??? I have seen way more folks agree than just you and I.

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