Spark Plug Fouling

[JohnStarry]

I recently rebuilt my entire motor on my 2001 YZ 250 2-stroke. it has been running great down closer to sea level, then i took it up to around 4000' to store and ride, it did great for the first few months, also i havent really been riding it much. now when i go up there to ride it it either wont start or will then ill pin it any gear usually 4th and it will foul the plug then i gotta change it. i was wondering if my oil was to rich(32;1) if maybe i can lean it out to like 50;1 to help clean some sludge out or do i have to just rip off my head and have it cleaned.

 

[robwbright]

http://www.ericgorr.com/twostktech/carbtuning.html