Here some good oil filter sites
Oil Filter - EMGO oil filter - part # 10-26920
i-bike site to purchase emgo oil filter
bellacorse site to purchase emgo oil filters
Also, check your local honda, kawasaki or suzuki shop. They may have this filter. I get mine 4 at a time from a local cycle shop for $5.50.
Call big4 cycles or your local triumph dealer for a multipack of sealing washers Triumph part number T3551092. This is a multipack of 25 washers. You won't need to bother buying this part for a long time after you buy this pack. You can also buy single sealing washer with part # t3550092
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