I try to do cross country racing but my question is should the rubber plug under the seat be on or off the bike to let more air in?
Its there to keep mud and water out and probably deaden the intake noise some. How many stream crossings are you planning to make?
You probably could sell it if you remove it, seeing their hard to find.
Raymond
Down East Pentons
The rubber plugs are available from Roberto "Parmabike" Ebay. I made my top airbox foam seals for the 73-76 airboxes from UNI Filter material used as packing when ordering new filters. Modern, 2 stages of foam and will last a lifetime! CIAO