Plug Fouling???

3 replies to this topic
  • Chris_Slade

Posted September 12, 2001 - 07:48 PM


HOW do you foul a plug on a 4 stroke?????? My dad has his 426, bone stock, no carb changes, and I have my 520, bone stock, no carb changes, and we have never had plug problems. What the heck are all of you guys doing?????

'01 KTM 520 SX
'95 KX 250
AMA Dist 6 Member
Hare Scramble Class B #523

  • Boit

Posted September 12, 2001 - 09:24 PM


Before you condemn many of these guys, you might be interested to know that the CDI unit was the culprit in many of these bikes. Also, some of the FCR had some manufacturing problems that allowed bleed-over from one circuit to another causing an excessivly rich condition at idle. So, to answer your question, WE guys are only trying to figure out what the hell is going on as well. When this plug fouling problem first reared its ugly head, the 4-stroke guys in the know had an inkling that something was amiss when some guys had no problems while others cursed their bikes. While you sit in judgement, we got busy and found the source of this problem and shared it with our fellow riders.

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  • Chris_Slade

Posted September 14, 2001 - 08:00 AM


I see, OK, that makes a little more sense. I just could NOT figure out how a four stroke was loading plugs, but a faulty ignition, that makes sense. I assumed it was something else, since with people always talking about jetting changes to a four stroke.

'01 KTM 520 SX
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AMA Dist 6 Member
Hare Scramble Class B #523

  • Bill

Posted September 14, 2001 - 12:14 PM


Some of us also had children, that loved to sit on Dads new bike and twist the throttle :)

Bill :D

99 WR400f, YZ timed, MX-Tech suspension, Scotts steering damper, White Bros E-Series (12 discs), tapered header and a/f. Kouba T-handle for the fuel screw. Works Connection billet throttle tube and frame guards. Cycra Pro-Bend, triple clamp mount handguards. Thumper Racing rad guards, Renthal Jimmy Button highs, YZ Tank and IMS seat, YZ number plate, odo removed, de-octopussed (Thanks Clark) EKP #4, 50PJ, 175MJ, 100PAJ and 65 SJ at 500-1000' Thanks James Dean!

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