Decide What Gears To Use
Cassette or freewheel?
There are 2 types of hubs you can choose from, cassette and freewheel. Many people also call them the freehub and the threaded hub. The difference between these two is coasting.
With a freewheel (threaded hub), you can coast backward. The pedals will stop rotating when you stop pedaling. The wheels, however, will keep rolling on. This hub usually sports 5-7 cogs. It’s from 120 – 126 mm in diameter.
A cassette hub, on the other hand, will make the pedals continue to rotate even when you stop pedaling. That means there’s no coasting backward on this one. Cassette hub usually sports 7-11 cogs. It has the ratcheting mechanism built right into the hub body.
Shimano HyperGlide is a very popular cassette many riders use today.
Next, you can decide what type of shifter pod you would like to have.
On the market today, you’ll find 3 common types of shifters:
- Twist grip shifters: you change gear by twisting the grip ends
- Trigger shifters: you change gear by clicking the lever with your index finger
- Thumb shifters: you use your thumb to shift gears
Shift rear derailleur
You should check the compatibility when buying this one. Is it for 6-7 speeds setup or something else?
You can see the total number of teeth capacity to make sure the derailleur will work perfectly with your cogs.
Things You’ll Need
Let us do some shopping and get you up and running with a new 8-speed bike featuring a freehub and Shimano gears.
Let’s get our hands dirty now!
- Cog set: Shimano CS-HG31 8-Speed Cassette (11-32T)
- Shifter pod: Shimano 8-Speed Rapidfire Plus Mountain Bike Shifter
- Shifter cable: you can choose any that you like
- Rear derailleur: Shimano Tourney 7/8-Speed Mountain Bicycle Rear Derailleur
- Allen wrenches and pliers
- A bright working space
This total setup will cost you around $58. We’re not including shipping fees. This is just an estimate.
The 3 main components you want to match are the cog set, the shifter pod, and the rear derailleur.
As you can see, we chose the 8-speed cassette (11-32T). So, we need an 8-speed shifter pod. Also, the Tourney 8-speed derailleur that can hold the max cog with 34T will be adequate for our need.
Getting things ready
Here are 3 simple steps you can follow to get the bike ready for installation:
Turn the bike upside down & place it on a bike stand if you have one.
Deflate your tires completely. Then, remove the chain. If there are brake cables on your bikes, make sure you remove them as well.
Using an Allen wrench, start loosening the nuts on the rear axles. If your rear wheel has a quick-release lever, you can use that to quickly uninstall the wheel.
Installing the cog set
Now, we move on to the fun part of setting up your new cog set.
If your existing bike has a threaded hub, you can use a small tool to unscrew the lock. If you have a freehub, you can use a screwdriver to unscrew the lock ring.
We advise you to replace the old threaded hub as well to make the upgrade work properly.
Then, take the cassette you just bought, the Shimano 8-speed in this case, and carefully align it with the splines or notches on the hub.
You can then push the cassette in a bit and put it into place against the wall of the hub.
Add a few drops of grease onto the lock ring of the new cassette. Then, tighten the lock ring using a screwdriver to secure everything.
Put the rear wheel back onto the bike. Now, you can pump air back into the wheel.
Installing the shifting mechanism
This part may be a bit tricky so check this out carefully.
Remove your handlebar grips. Then, slide the shifter pod (Shimano 8-speed Rapidfire) onto the handlebar. Put your grips back on to secure the shifter in place.
Place the shifter cable along the frame of the bike. Lead it to the rear axle.
Put the rear derailleur onto the frame, near the rear hub. Then, lead the shifter cable into the slot decided for it on the rear derailleur.
Put your bike chain back on. Place the chain at the center cog of your cassette. In this case, the 4th cog of the whole 8-cog collection.
That’s pretty much it!
If you’ve selected your parts correctly and followed through the steps above, your bike should now be up and running.
Remember to test the shifting first before taking your bike out for a spin. On a flat surface, you can try changing gears to see if all components incorporate well with each other.
Also, check the wheel bearings to make sure your bike rolls fast and smooth.
Please keep in mind, the above steps are for instructional purposes. You can most definitely choose your own gears and setups.
This is a DIY quick guide for folks who love to tinker with their bike. However, it may not be for everybody.
If you find some of the steps confusing or you are still unable to convert your single speed to a multiple speed, please reach out to a professional.
If there are any bike shops near you, make sure to pay them a visit if you can. You can send us a message if you’re stuck at any steps. We’ll try to help you out the best we can.
We guess this is goodbye for now. We really hope you enjoyed reading the post as much as we enjoyed making it. Remember, the sky is the limit when it comes to upgrading or downgrading your bike.
You should also make sure you understand some of the basic mechanics first before tweaking things here and there. Always do a test ride before real riding. We don’t want to sound like your mom, but she’s right, safety is the #1 priority. See you next time!