Question about 2005 Honda CR 125 R

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Spark keeps fouling but no clue why

The spark blug keeps fouling but the oil mixer is fine just the spark plug gets real oily and only funs for bout 20 then fouls

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Are you losing gear oil.
When the crankshaft seal leaks, oil from the gearbox is sucked into the crankcase, and this can foul the plug.
Also check the plug gap, most guys set the gap too small. It should be 0,7mmto 0,8mm. The plug should be a B9 EG, or equivilant.
Now, you can also change the plug cap to a type that has a built in resistor, this also helps with plug life.
Note that 2 strokes use plugs way more than 4 strokes, and you should replace the plug every 15-20 hours to keep your riding pleasant.
Good Bike you have there

Posted on Feb 16, 2009


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Hi Josh:
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Keeps fouling plugs

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