Doing a 230km / 142 mile cycle this weekend over 2 days, what vital equipment am I missing? This will be my first long distance cycle over 100km's / 62 miles. 
Last weekend I did a 60km / 37 mile cycle without too much difficulty, so I'm pretty sure I can get through at least day 1, day 2 will be a struggle but then again I have the whole day on Sunday and can move as slow as I want. 

This is the gear I am going with :

Bike: Trek 7.2 FX (2011) (Stock standard, no mods) - recently serviced!

Pants: decent mountain bike cycle pants with pads (not sure on the brand, but a good pair)

Shirt: regular cotton t-shirt (nothing fancy)

Jersey / Jacket : None

Backpack : CamelBack HAWG 20 - holds 3l of liquid. 

Nav : Garmin Dakota 20 with heart monitor - and map planned - route broken down into 5 stages routing along cycle paths mainly, no major roads, except for the odd crossing here and there. 

Shoes: Beach style summer sandals with velcro straps - no socks! 

Contents of backpack:


1x Spare inner tube
2x AA battery spares for the Dakota
1x MP3 player with charging cable
1x Phone with charging cable 
Initially 3l of pure cold water in the reservoir
Wallet (cash + credit card + id + medical insurance card)
Puncture repair kit
1 x pump (nice and compact and proven to work)
1 x Camera and charger
1 x Clean underwear change. 


Food and additional drinking material I intend to buy on route until I get out far into the country after about 50km's then I'll buy some stock for the road. 

What have I missed, and any additional tips for this ride are welcome. 

Last thing I would like to add, I've read on some sites that listening to music while cycling isn't advisable, what would you say? 

Should I take some form of self protection for the road? Mace or maybe a hunting knife - I mean you never know? 

Thanks guys - look forward to the responses.
Perhaps a little late (sorry, I was on a week-long bike trip), but:

You're missing sun lotion.  You definitely need it and should apply it first thing in the morning, since you will likely be reluctant to stop to apply it later.

Despite what the others have said, I've never had a problem wearing the same cycling shorts 2-3 days in a row.  I do use chamois cream, though.

I typically ride with cotton T-shirts and find them comfortable.  Change shirts daily, and have a spare to put on if you get soaked/chilled in a rainstorm.  I have a synthetic (forget the material) soft knit jersey for cooler days, and sometimes wear sweat pants (with double leg straps) in the morning if it's too cool (since my muscles no longer tolerate cold well).

I never travel (any distance) without rain gear -- jacket and rain pants.

You need to carry some ready snacks -- heat-tolerant (assuming it will be hot) candy of some sort, or "energy bars", or "trail mix" or such.  (Whatever it is should contain a decent amount of salt, and potassium is a bonus.)  If you begin to get fatigued, stop (in the shade, if possible), rest for 10-15 minutes, and have a snack plus extra water.  (And, of course, chocolate milk is good for temporal fractures.)

I don't recommend riding with ear buds, but I can understand how others might.  For me the voices in my head keep me plenty entertained.  At the very least, though, keep the volume low and don't use them in traffic or where other cyclists are likely to be overtaking you.

The only "protection" I've ever needed is against dogs, and that is fairly rare.  I used to have a bike with a pump peg, so I could quickly grab the pump and wave it at a threatening dog.  Yeah, the pump weighs all of 8 oz and couldn't hurt the dog, but to him it looks like a big black stick.  With my current bike I must use a pump strap, but have not needed to fend off a dog in several years.

A pocket knife is useful for the odd job on the road, though (if nothing else, cleaning your fingernails).  Beyond that a few basic tools, some small zip ties, and a bit of duct tape or hockey tape.

A flashing taillight is very lightweight, cheap, and can greatly improve your visibility in poor conditions.  A headlight is nice to have but not as necessary.

I personally don't like having stuff on my back.  A handlebar bag is OK, and easily accessible, but distributes the weight poorly and bounces around.  A saddlebag (strapped to your seat rails) is a slightly better choice, though usually of limited capacity.  I've never used them, but there are also bags that strap inside the frame, between the top bar and the down bar, and they should be stable and capable of carrying most of what you need.  (They tend to block the use of water bottle cages, though.)  But if you plan to do much of this a rack and panniers is the way to go.

If the terrain is reasonably flat and the weather cooperates then 142 miles in two days should be easily obtained (ie, I could manage it, and I'm a 63-year-old polio survivor).  Hills, rain, or a headwind could make it unpleasant, but it should still be doable for a healthy younger person.