Yep, the tyre pressure is too low. I know about that, and I had the adaptor for filling them up at the nearest gas station in my pocket, but I didn't manage to do it until then. I never said it wasn't my fault.
Pumping up bicycle tyres (or rather inner-tubes) at air-lines designed for cars is a bad idea. The gauges are inaccurate, especially at the high pressures (relative to typical car tyres) used for bikes, and many have mechanisms that deliver air in "bursts" which are fine for high-volume/low-pressure car tyres, but can blow the tyre off the rim on high-pressure/low-volume bicycle tyres. The worst pumps in this regard are the ones where you set the target pressure on the pump, and the pump decides when it has reached it. With Schwalbe Marathons (I ride those too!), if you are pumping them to their minimum pressure, you will
probably get away with using a car air-line, but what you
really want is a floor-pump. I recommend the
Topeak "Joe Blow" range; I bought the cheapest that had a built-in pressure gauge years ago and it is still going strong. You will want to carry a pump on the road as well, and if your budget will not stretch to two pumps (or you have nowhere secure to store a floor-pump), I suggest the
Topeak Morph range. No, I don't own shares in Topeak
, but their pumps are good, and I own two.
It certainly needs cleaning (I am reluctant to do this because it will take approximately 0.212 seconds cycling to uni next week before it's covered in mud again
As I recall, your bike is something like this:
You have mudguards (USA:fenders), so you are off to a good start. The problem is that the mudguards are way too short. They always are because bike manufacturers are obsessed with people breaking them on kerbs. Unfortunately, that means that the front one does
nothing to protect your bottom bracket, sprockets, mech, chain etc. or even your feet. The rear mudguard is less critical, since it is long enough already to protect your rack, saddle etc., and extending it, while not a bad idea, mainly protects riders behind you.
The answer to your problem is
mudflaps (insert inevitable "I herd U leik Mudflaps" joke here
). You need to remove the silly little plastic "tail" from your mudguards (usually you just have to drill out the rivets that hold it), then cut a long flap from rubber matting, and "sew" to the rivet-holes with nylon cable-ties (the cyclist's friend). The flap should be cut long enough to nearly touch the road. No, mudflaps do not add style to your bike, but they are the answer to mud on the drive-train and your feet.