P/No: 11170 for a EVO motor.

Can't help with the size offhand sorry, but if you are in one of the metro areas, bearing suppliers can cross reference and match from the original if you have it ?

I just bought a 500 piece silicon o-ring kit from Amazon fro $30 for my airgun.  Its got a lot of sizes in it which would also fit a harley.  maybe try one of these kits and then you have a good set on hand for the future.

No idea on the accuracy :

O-Ring
for Air Control solenoid
fits FLT late 1985-1996, FXRT 1984-1993
crank sensor Touring 1995-1998
rubber, black
ID x OD: 14.4 x 18 mm, 1.8 mm thick
replaces Harley-Davidson part number HD 11170

Thanks for all the replies, much appreciated.

Future reference for HD-11170

Ive gotta ask... what Evo crank sensor are we talking about? They dont run a crank sensor do they? (in the same way as a TC), its the sensor in the timing cover?

1997 EVO Crank Sensor is in the same location as the Twin Cam Sensor.

The more you know! The thought it was EFI related did cross my mind but Ive never actually seen them or noticed them.

Cheers!

It does beg the question as to whats behind the timeing cover ....  

Timing cover inner, then the cam position sensor.