Dead spark plugs???

Question

What causes spark plugs to die after about 100 miles of riding?
its a suzuki rf400r 93. it could be i of these 3: CDI , Coils, or carbs, unless i am missing something?
coils are giving power to the plugs.

Answer 1

Spark plugs can be "fouled" quickly under certain conditions, such as using a plug that is too "cold". residue can build up on a cold plug and foul it out. Try running a slightly hotter plug.

Example: if the # on your plug is B8ES, change to a B7ES, which is a plug with a hotter tip temp, which will burn off the residues that are fouling it.

Consult your local M/C service center. They can advise you regarding your specific model better than I can.

Good luck.

Answer 2

OK. Try your HT leads and also make sure that your spark plug caps are OK.

Take Spark plugs out and see colour (Running too rich or thin will show up on black/white coatings on anode - answering the carbs question). You might also want to check the sparking distance.

After this, you might want to look at timing. Other than the battery and switch, these are the oly things it might be, other than coil.

Luck

Answer 3

Compare your plugs to these;

http://www.ngksparkplugs.com/techinfo/spark_plugs/faq/faqread2.asp

This will give you some idea of whats going on inside your engine.

Are you using the recommended plugs ( I believe they should be CR8EK or CR8EIX). Are you using new plugs & they're failing after 100 miles or are you trying to clean & reuse the old ones? (not recommended)

Give us an idea of what the colour of the plugs is telling you, could be several things need more info.

Answer 4

Spark plugs do not `die' they just become inefficient when clogged-up with residue. However, the spark can die when the ingnition system is faulty. Back track through the system and eliminate the possibilities one by one (i.e. Battery, ingnition system, HT lead.)

Answer 5

Try a different grade of plug some plugs run at different temperatures better than others

Answer 6

Forget your carbs - they should not be the prob

Coils can break down - albeit rarely and cause breakdown of output to plugs!

Would suspect the electronic ignition to be honest

Answer 7

It could be running lean, which causes excess heat to build up in the cylinder, causing pre-detonation & excessive heat in the electrode, either burning away the electrode or causing the actual center of the plug to overheat, & contact to be lost, check yer mixture mate!!!