Mate picked it up for 1500 bucks. it rides well in all gears except 2nd. In 2nd at cruise throttle, its ok, but power on and it skips out and makes a grinding noise. Any Ideas what it is, ie, selector, or 2nd itself is shagged. Is it common? How do the gearboxes come apart in these, can you slide the whole thing out and replace, or do you have to rebuild the guts? I'm clueless on gearboxes, so any help appreciated. Thanks, Tim.