I own a 400, did it´s 1st season of supermoto back in 2000 and ran about 50 hours on it until the low end seased. ever since then I do a low end/con rod rebuilt every 40hrs, because the 1st time I was lucky that anythig else got thorn apart, but i´ve seen engines totally trashed whith gear box, crankcases, cilinders destroied because of this. its odd that litlle few people ever mention this, because this seasure happens more than any other part failure( piston, valves,). in some cases there may be a gear box problem, it depends on the rider/riding style, but sooner or latter the low end will seise. I´m asking you guys, because seeing few people complaining makes me wonder if I´m not trowing money away money too soon. running only supermoto might have sommething to do whith it too, but I would like to know how long your bottom end last?