On my ktm race bike I run 12mm to 14mm adjustable offset clamps from reb barron. I agree with above post...20mm is a dirt offset. I think the website is redbarronracing.net but I know there was another site listed in one of the threads that build a whole mess of different clamps if you do some hunting around.
Haha, thats kinda random! I get a whole season of racing...practices, open track, qualifying, and two races per race day. I can get back to you on actual hours on motor per rebuild but I just do it once a year just to be safe/and add cooler parts. Haven't had an actual engine problem yet except for a loose spark plug boot.:bike: