Late model KTM/Husky 2-strokes are fitted standard with Mikuni TMX 38mm carburetors from year model 2017. However the block seal appears to be a very poor design and causes a leak, impacting idle and bottom end performance. This video shows how to disassemble the carburetor and where the block seal is located. I personally no longer use the Mikuni carburetor on my 2017 250 EXC, but thought it would be of interest to others who are still using the Mikuni.
JDMK05 Block Gasket Kit: https://www.tokyooffroad.com/product/mikuniblockgasketkit/
KTM Talk discussion thread: http://ktmtalk.com/showthread.php?543163-Mikuni-jet-block-gasket
2017 KTM 250 EXC with Keihin 38mm + STIC & RK TEK Head
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