the Kaw p/n is 92055-1639
I just have'nt had the ambition or spare time to pull the damn sensor out and measure the groove size...
McMaster Carr has "quad" rings (they have 4 lobes, kinda like a shamrock shape in cross section) that seal much better than a simple round cross section ring, they have them in
Viton and Buna...
and in the sizes I can estimate (3/32 or 1/8 cross section) would cost about $0.12 each...you could buy a sack of 100 for the price of 6 at kaws price.....
somebody find the "dash" number for this part, I have searched all the Kaw parts sites hoping to find a cross reference on the size... it's either a -1xx or a -2xx part number in "o-ring lingo" for a 3/32 or 1/8 section.
http://www.mcmaster.com/#o-rings/=m9g9jzoh, STANDARD o-rings in this size range run about the same price for
100 pieces as Kaw charges for 1 piece...( approx $2.50)