Your best and cheapest option in my opinion is to do this (it's what I did). Get a bearing carrier from ebay for a 250X / 300EX / 400EX (same carrier 4 all 3 machines and cheaper because of availablility). Then you'll have to get a rear sprocket and the 4 mounting bolts for a 1986 350X (from you local Honda dealer - not that expensive) to make it work. The 1985 rear sprocket bolts won't clear the carrier. You'll have roughly $150 - $175 into the whole set up. Just my opinion!