12mm I'm sure and other side is 17 or 19 (I put som hex head bolt to hold it)

Last edited by Grzegorz; 06/16/2007 6:50 AM.
Grzegorz ......55 cubic inches http://www.flickr.com/photos/25172906@N06/ 904WisecoTPUSAcamsTTPignitorgutted Airbox"breath"airIntakeKeihinCR-ScarbsBlackEpcoExhaustS/SwheelsPortedPolishedHead