Why do you need one pretty bad? Look around the vehicles section in the mods tab or in the forums and don't reply to another thread that hasn't been replied to for an long time unless necessary or constructive. Also make sure to look if the forum thread has an tag to the left of the title saying outdated or on hold or any other tag.
https://www.dropbox.com/s/t6vh9iuzo7tcp7b/5_24_14_trx450r.blend?dl=0 The last touched blend file I have of it. https://www.dropbox.com/s/l4fw45em71fjbxh/alpha450r.rar?dl=0 Latest packaged file i had left of it. I would love to see someone take this old project and revise it and bring it to light! Still needs alot of work.. 2 year old jbeam files are practically incompatible with the latest beamng stuff. And needed the rest of the plastics modeled for the fourwheeler. I wanted to pay my respects to my old project by sharing it with all!
wow first time i've seen the OP bump his own thread xd naw, just messing. Sadly i would but i dont have enough experience to do it justice