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The O-Ring Mod for an FCR


This is an easy job and does wonders for getting rid of the bog that many with an FCR-MX (Only, regular FCR's use the 'Taffy Mod') experience. It can be done with the carb on the bike.

I use a #78 O-Ring (7/16" O.D. X 1/4" I.D. X 3/32" thick) from the plumbing dept. of nearly any home improvement/hardware store. Cost is about $2.00 for a box of ten, share with your pals!

1) Remove the throttle wheel cover from your FCR.

2) Work the O-Ring over the timing adjustment screw.

FCRO-Ring1.jpg FCRO-Ring2.jpg

3) Pull the O-Ring over the black AP cam thusly.


4) Re-install the throttle wheel cover. Just that simple!

Images courtesy of DouglasGraham, staff photographer

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