Reddit mentions of M19 Bicycle Multi-Tool - Steel Bike Tool, Torx, Hex and Chain Tool Compatible

Posting pictures of the bike would be helpful. If you decide to do this, make sure to post a few high quality shots of your drivetrain which could show us if there's any critical wear.

However, before you post the pictures, it would be helpful to clean the bike. Get a bucket of soapy water, find a sponge or rag that you don't mind sacrificing and get to cleaning your mountain bike. Dry it off, and then post the pictures (that will make any critical deficiencies more obvious).

As others have mentioned, you'll most likely need to remove the chain. Here's a video from one of the best cycling channels on Youtube, Global Cycling Network (GCN), that shows you exactly how to do that. GCN and its sister channel, Global Mountain Bike Network (GMBN) offer a number of fantastic maintenance videos in addition to a variety of other content. If you're wondering where to get a chain tool, I would just spend a bit of extra money and get a good multi tool like the Crank Brothers multi tool which already comes with one.

Pump up the tires to see if they still hold air. If they do, fantastic. Nothing more needs to be done. If not, you'll need to get new tubes (most likely your mountain bike will need 26 in X 1.9-2.125 in tubes). Here's how to install a new tube.


As a bike commuter, you'll need a number of things to stay safe and make sure your bike stays in your hands. Here are the essentials:

1. Front and rear lights. I use this flashlight for my front light, and a rear light similar to this.
   
   
2. A helmet. From your posting history, you seem to live in Australia. All helmets sold in that country are required to meet the same safety standards so in all likelihood, spending more on a helmet will not make you safer. Buy one in a store and you're set.
   
   
3. A great bike lock. Read this to learn the proper way to lock your bike.
   
   However, staying safe is only the first part. You'll want or need a number of other items to make sure that your commute isn't frustrating. Here are some of the items off of the top of my head.
   
   
4. Bike pump. If you're going to mostly ride near gas stations which have air pumps that can inflate a tube, you probably don't need to carry around a mini pump on your rides. However, everyone should own a floor pump.
   
   
5. Degreaser. The cheap automotive kind is fine as is WD 40. This is used when you need to clean the drivetrain.
   
   
6. Bike lube. Stick with a bike specific one.
   
   
7. Disposable poncho. When I lived in an area where it often rained, I always had a dollar store disposable poncho in my backpack. It's just super handy if there's an unexpected downpour.
   
   
8. Fenders. I personally don't have them, but I live in a relatively dry climate. If you live in a place where it always rains, they're super helpful.
   
   
9. Bottle cage. A cheap plastic one is fine.
   
   
10. Tire levers.
    
    
11. Rear rack. Assuming you don't have a full suspension mountain bike and instead have a hard tail (here's an article if you're unsure), get a rear rack. Do not get one that is only mounted to the seat post like this Ibera, but rather one that connects to the bike frame. If your bike does not have any bolts that can attach, you can use P clamps to secure the rack. This post describes how to do just that.
    
    
12. Some way to transport groceries. While I use a milk crate that I ziptied onto my rear rack with bungee cords on top of the crate (similar to this setup), many others use panniers to transport groceries and other goods. This has the benefit of more storage, better center of gravity, and can be water proof. However, they are usually much more expensive unless you go the DIY route.
    
    
13. Bike bell. Cars won't be able to hear you, but if you ride in areas with lots of pedestrians or other cyclists, it's useful.
    
    
14. Spare tube. Fortunately 26 in tubes are cheap and super easy to find. Any department store with a bike section will carry them.
    
    /r/bikecommuting can be a helpful resource if you have other questions.

http://www.amazon.com/dp/B003YMYX5E/ref=cm_sw_r_udp_awd_rKwqtb1RC22JE

Just click on the silver color one, and it's the same one as the link from the other website.