Ive got a 2004 wr450 with a street title. Today i was riding home from work and i decided to take a little detour and hit some dirt roads up. I went around a turn shifted into third and when i opened her up it only got to about half throttle then the power just stopped. It was working perfectly fine up until that point. Now in any gear it idles perfectly, works good up until about half throttle and its like someone turns the off switch. It just bogs (thats the closest way to describe it) and wont go any faster.
It still starts first kick, idles goods, oil is new and good, coolant is good. It was getting dark when i got home so thats all i could check. What else should i look for to find this mysterious instant loss of power about half throttle?