I Recently purchased A 2011 Polaris Sportsman 400 H.O. from a good friend who had accumulated too much credit card debt and needed help to keep from drowning. It has been adult maintained and has less than 500 miles on it. I am not an ATV person and am, in fact, retired, but it is now mine and I do like it. My problem is that I only crank it about every 8 or 9 days and only ride it for 10 minutes up and down my dead end street. I thought that was sufficient to keep the battery charged and easy to crank, but not so. When I turn the ignition switch key, it grinds like a starter or solenoid problem and of course will not crank. I then check the diagnostic mode and usually find 10.5 volts, so I put the battery tender on it for a day or so. In most cases it will eventually crank, although the grinding noise is still intermittently there. I would like to remove the conventional battery and at least check the fluids, but cannot figure out how to do it correctly. It sits behind the left rear fender and cannot be lifted straight up and then forward to me because of lack of clearance from the inside top of the fender. I do not want to tip the top toward me as the manual says not to do so. In addition, the negative terminal cable is somewhat loose on the bolt/nut combo and cannot be tightened because the bolt and nut are turning together and I cannot get a wrench on the nut to hold while I tighten the bolt. Does it seem possible that the solenoid or starter is the problem or could it more likely be that the somewhat loose negative terminal cable is the culprit ? If I can upload successfully, there will be a picture of the battery setup. I would appreciate your thoughts and expertise. Thanks.