this is something i have been toying with at present see my crank overall width topic, i have ended up shimming my main in gear side 0.4mm to get my crank to sit bang in middle, i had a overall clearance of 0.8mm. which appears to be normal and a lot of people have kindly confirmed it. this site and members has helped me no end, if i could work out how to post my pics on here i could show u what i did.