Do I need a new bike or should I upgrade my current one?

I currently use a mountain bike that's about 20 years old and the brakes are pretty shoddy (the front brake cable snapped a few days ago, about a week after the rear cable snapped). It has 3 gears on the left and 5 on the right (I don't know the bike gear lingo so I hope that makes sense) but if I use any gear on the left other than 2nd gear, my bike makes quite a loud noise, so I don't know if I need to fix the crank.
I only use my bike on a 5 mile commute (there and back) to the gym every morning, so I feel (and I've been told in a thread that I made) that buying a new bike wouldn't be that beneficial to me, plus, my current bike is much safer as it's 20 years old, muddy, not flashy at all and is made of a multitude of different parts from different manufacturers (eg my pedals are different).
Should I get my bike checked up and replace my brakes or get new wheels, or is it worth replacing it with a new bike?
I only use my bike on a 5 mile commute (there and back) to the gym every morning, so I feel (and I've been told in a thread that I made) that buying a new bike wouldn't be that beneficial to me, plus, my current bike is much safer as it's 20 years old, muddy, not flashy at all and is made of a multitude of different parts from different manufacturers (eg my pedals are different).
Should I get my bike checked up and replace my brakes or get new wheels, or is it worth replacing it with a new bike?
0
Posts
http://www.bikeradar.com/forums/viewtop ... t=13087008
There is no secret ingredient - Kung Fu Panda
London Calling on Facebook
Parktools
Some items may just need adjustment whereas others will need replacing.
At this point you can work out how much it will cost and this will determine whether it is worth buying new or good s/h components or a new or good company condition s/h bike.