I took my GN250 for a ride on the weekend and later that afternoon looked at my rear wheel. It was flat. I tried pumping it up but it seems the valve is leaking. I was thinking it would be easy to just take the bike in to get it fixed but the trouble is getting it to the shop. I am very mechanically minded and have fixed cars all my life so I was thinking that it shouldn't be too much trouble removing the rear wheel. I've never had a bike before so was wondering if this is something I should do myself for the first time or should I leave it to the experts considering it could be a serious problem if the wheel isn't put back on properly? Just wondering if its something people generally steer clear of or something that is common practice.