In this how-to, we’ll be changing the stock freewheel of the RadExpand 5 with an upgraded freewheel. The RadExpand comes with a 14-32 tooth freewheel. In this tutorial, we’re upgrading to an 11-34 tooth freewheel that can be purchased online from Amazon. This will provide a higher gear for a little more top speed and a lower gear for better climbing.
Most of this tutorial covers how to remove the rear wheel from the RadExpand. This is useful to know, even if you don’t plan to change the freewheel. Changing the freewheel itself is very simple with the right tools. In fact, as I was upgrading the freewheel, I also replaced the tube in the rear wheel. I had accidentally popped it when overinflating it with an electric air pump.
Disclaimer: By following these steps, you take the responsibility for any damage that may occur.
Tools that you will need:
- 4 mm hex wrench (Allen wrench)
- 18 mm wrench
- Crescent Wrench
- Wire Snips or Scissors (wire snips are better)
- Zip Tie
- Freewheel Removal Tool (on Amazon)
- If you have trouble loosening the nuts for the rear wheel, I’d recommend an 18 mm rear axle nut removal tool (on Juiced Bikes)
- Gloves! I didn’t have any, and I’ll be washing my hands for days trying to remove the grease!
Parts that you will need:
If you still have the assembly tools that were sent with your RadExpand, you’ll already have most of the tools you’ll need. The only other tool that is necessary is a wire snip to cut the zip tie on the motor cable. You’ll also need a zip tie to replace the one that you’ll be removing.
If you have a bike stand to support the weight of the RadExpand, that would be great. If not, you can turn the bike upside down. That’s what I did.
I recommend taking photos or videos of the parts as you remove them, so you’ll remember what goes where and in what order.
Because we’re not making a huge change in the bike’s gear ratio, you don’t need to buy a longer chain or add any links.
- Remove the battery. This will eliminate the possibility of blowing a fuse or damaging the electrical components of the bike. It also makes it lighter to lift and/or flip upside down.
- Take photos of the nuts, bolts and washers, so you’ll know where they go and in what order.
- Switch into the highest gear (Gear 7) so that the chain is on the smallest cog on the freewheel.
- Place the bike on a bike stand that can accommodate its weight, or flip the bike over upside down. Tip: Hold the rear brake lever when flipping the bike upside down, so you can control the bike better.
- Get all the tools you need ready. I probably spent as much time looking for tools I needed as I did using them! Have a clean spot ready to place the nuts and other parts you’ll be removing, so they don’t get lost.
- Use wire snips or a good pair of scissors to cut the zip tie holding the motor cable to the frame. Be careful not to damage the wire insulation. Wire snips work better than scissors and are less likely to damage the cable.
- Unplug the motor. Always be careful with the motor cable, so it doesn’t get damaged.
- Use the 4 mm hex wrench to remove the bolts for the derailleur guard and fender stays. There is also a torque arm on the left side of the wheel that will need to be removed. This is important to reinstall, so don’t misplace it.
- Remove the chain from the chainring and let it hang loosely, so you can move the derailleur out of the way when removing the wheel. I would definitely take a picture of the derailleur and chain before removing the wheel, so you’ll know how the chain is supposed to be positioned when you reinstall the wheel. This can be confusing, well, at least to me, anyway.
- Use an 18 mm wrench to remove the axle bolts. One should have come with your bike if the bike was shipped to you. If you have problems removing the nuts, I’d recommend an 18 mm rear axle nut removal tool. One of the nuts came off easy for me with the wrench provided by Rad, but I had to use the removal tool to get enough leverage to remove the other.
- Once you have the nuts removed, lift the wheel carefully out of the frame.
- Removing the freewheel should be fairly easy. There is a nut that you’ll notice that has a tab facing outward. Remove this to a safe spot. You’ll need the freewheel removal tool and a large enough crescent wrench to unscrew the freewheel. Turn the wrench counter-clockwise. (See photo below) I placed the wheel standing up on the ground, so I could get enough leverage to break it free. Continue unscrewing counter-clockwise until you can remove the freewheel from the bolt.
- It’s simple to install the new freewheel. Simply screw it on clockwise. You may need to use the freewheel removal tool at first to get it started. You don’t have to tighten the freewheel too much, just snugly.
- And that’s pretty much it! Now your bike has a new freewheel. To reinstall the wheel, just follow the steps to remove the wheel in reverse. Make sure that washers, the torque arm, and bolts are reinstalled in the proper orientation and place. You’ll need to install a new zip tie for the motor cable to keep it snug against the frame.
- Once you have the wheel and chain reinstalled, you may need to adjust the derailleur to shift smoothly. Luckily, I didn’t run into this issue.
- Before riding, make sure that everything is tightened properly. Since the bike and I wound up wearing a lot of the grease from the chain, the chain may need to be cleaned and re-oiled. Actually, this is a good time to inspect the bike and clean it.
Below: Tools and parts needed for this project
Below: The chain removed from the chain ring and hanging loosely, so rear wheel can be removed.
Below: Torque arm that needs removed using a 4 mm hex wrench
Below: Removing derailleur guard and fender stay
Below: Removing nut from axle bolt using an 18 mm wrench
Below: If you have trouble removing the nut, an 18 mm pipe wrench will provide more leverage. I purchased this a few years ago from Juiced Bikes.
Below: Freewheel removal tool. You’ll need this to unscrew the freewheel.
Below: Before using the freewheel removal tool, you’ll need to remove the washer on the axle bolt. Keep this in a safe place. And if you notice, I was also changing a tube on the rear wheel when I did this upgrade.
Below: Place the freewheel removal tool around the axle bolt. Use a crescent wrench to unscrew the freewheel. Turn counter-clockwise.
Below: The new freewheel reinstalled with the tabbed washer in place. Make sure the tab faces outwards.
Below: When reinstalling the wheel, make sure the tab on the washer is facing outwards on both side of the bike. Make sure to reinstall the torque arm.
Below: The new freewheel installed on the RadExpand, and a very greasy frame.
I hope this tutorial was helpful. It’s a great idea to become familiar with your bike and be comfortable removing the wheels for tube and tire replacement in the future. It can be a little tricky and first, but with practice it will become second nature. It definitely helps to have the right tools. The axle nut removal tool I bought from Juiced Bikes was a godsend for me, since axle nuts can be very hard to remove.
Keep all of these tools in a handy spot, so you don’t have to look for them each time you do maintenance on your bike. Usually the most dreaded part of bike repair for me is trying to round up all my tools because I have a habit of not putting them back where they belong. But I’m getting better!
As far as the difference the new freewheel makes, there is less ghost pedaling. There’s definitely more resistance when pedaling in the highest gear, which I prefer. Since the motor cuts off when the bike reaches 20 mph, you won’t gain much speed from the new freewheel, but it will be a little faster. I upgraded mostly to eliminate some ghost pedaling.