Mikuni BST40 Flat Slide Carburetor Diaphragm replacement instructions.
Remove the old plastic retainer from the
throttle slide with sharp knife as shown.
Plastic retainers warp and leak with age.
Use a 1/8" drill to open the holes slightly to fit
the rivets. Air filter side of slide shown. Use
aluminum rivets only.
Be sure the spring guide stud
is not bent and the spring
does not rub on the hole in the
diaphragm or slide.
A mark of paint can make
it easy to get the slide
back in facing correctly in
the future.
$29 each
updated 05/28/15
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