Before selling you motorcycle you must value it to get the exact value. The valuing will include the value of the motocross gear you posses, the value of the bike itself depending on the market situation which could have made it appreciate or depreciate in value, its age and the additions you have installed.
The availability of the maintenance facilities as the spares and other motorcycle accessories will add it marketability. People will prefer to buy machines which are well supported by the manufacturer. This will create demand which will affect the price you tag on your bike.
Fox Racing brand will be of more advantage for if have the full kit you can decide to sell it as whole or as individual kits thus making more money. Despite the depreciation you should aim for the highest profits possible. Also on top the above you should not show the urgency to sell to the potential buyers.
Sometimes you may have a yamaha part that you have stocked and never used hence you sell it separately from the other items. The item should increase your profits and give the buyer the feeling of having a supported machine. There are many ways you can advertise your motorcycle depending on its value like the internet, the media or placing the on sale poster.