There’s nothing more frustrating than wasting time fixing your go-kart while you’re out at the track or trying to enjoy quality time with family and friends. One of the most common issues that go-kart enthusiasts run into is having a chain that keeps falling off their kart. Not only is this situation inconvenient, but it can also be quite dangerous for both the driver and other racers.
The chain is the connection point between the transmission (or crankshaft) of the kart and the rear axle, which is connected to both rear wheels. It uses a series of sprockets on which the chain runs and when operating correctly does so without incident.
If you’re staring at a chain on the ground next to your kart, you’re probably wondering how to fix it and what is causing the issue. In this guide, we’ll be taking a look at how to fix a go-kart chain that keeps falling off the sprockets.
Here are the most common reasons why your go-kart chain keeps falling off:
- Wrongly Sized Drive Chain
- Go-Kart Chain Is Worn Out
- Misaligned Sprockets
- Worn Out Sprockets
- Bent Go-Kart Frame
- Deformed Axle
1. Wrongly Sized Drive Chain
Quick Summary:
- Determine desired chain length
- Remove the master link and chain from the sprocket
- Shorten the chain accordingly before installing it again
One scenario that you could be confronted with is having a wrongly sized chain on your sprockets. After you install a go-kart chain – even if you’re replacing an existing one – you’ll need to ensure that it fits perfectly. In order to ensure a perfect fit, it would need to be adjusted. If your chain is not adjusted correctly, it can jump off the sprocket teeth and completely fall off your go-kart!
How To Fix It:
Adjusting the chain is not a complicated procedure and can be done with basic, inexpensive tools. If you have a chain-link removal tool, this will be much easier for you. I highly recommend picking one up since they are so inexpensive and can save you a ton of time in the long run. I’ve written a separate guide on how to adjust a go-kart chain, but have summarized the main points below.
Tools that you’ll need:
- 1 x Chain link removal tool
- Working area
or - 1 x Hammer
- 2 x Nuts
- 1 x Nail (smaller than pin)
- Working area
Once you’ve gotten your tools and working area set up, we can now start shortening the chain. I’ll summarize the main points below for easier understanding. Feel free to read the in-depth guide if you require more detailed instructions.
- Locate master link and disconnect
- Carefully measure how many links need to be removed by pulling up slack until 1/4” to 3/8” of slack remain and remove the chain from sprockets
- Use either a chain link removal tool or a hammer and small pin to remove the individual links
- Reconnect the chain with the tool or by hammering in the pin
2. Go-Kart Chain Is Worn Out
Quick Summary:
- Replace your go-kart chain with a new one.
- Don’t try to fix a worn out chain as it will eventually snap
Over time the chain on a go-kart will start to wear out. The main symptom of a chain that is wearing out and that it becomes elongated and when this happens it will no longer properly fit on your go-kart, which means that it can come loose from the sprockets. You’ll be able to notice that the amount of slack on the chain has increased.
How To Fix It:
First off, it’s completely normal for a go-kart chain to wear out over time and it’s just part of the maintenance when owning a go-kart. In order to fix this issue, you will simply need to replace your chain with a new one since repairing it isn’t a good idea.
This is because worn chains don’t have the structural integrity to remain intact for much longer and can snap at any time. You should definitely avoid this! So, simply replace your chain with a new one. If you need more information on which chain you need for your setup, you can refer to this go-kart chain size chart.
3. Misaligned Sprockets
Quick Summary:
- Align sprockets with a straight pole by removing the sprocket keys
- Turn axle or wheels and let the chain align sprockets
- Use a laser alignment tool for better accuracy
Sprockets on a go-kart must be in alignment to work properly. If one of the sprockets is misaligned with the other it can lead to the teeth on the chain not completely setting in the sprocket. If this misalignment is severe it can cause the chain to jump off the sprockets completely and the entire chain will fall off your go-kart.
How To Fix It:
In order to ensure regular wear of your chain, you’ll need to align your go-kart sprockets. We’re talking about the sprockets on your crankshaft or clutch and the rear axle sprockets.
There are multiple ways to fix this and I’ll outline the most common one. Feel free to read my complete guide on go-kart sprocket alignment. In order to ensure alignment of the two go-kart sprockets, here are some quick tricks:
- Use a long, straight pole to ensure that the two sprockets are aligned. (You can do this by removing the sprocket key and pressing against the outer edges of both sprockets)
- Turn the axle or the wheel to align the sprockets by letting the chain pull them in line. (Simple back and forward movements will suffice)
- For more accuracy, use an alignment tool that is specifically designed to maintain alignment. A laser alignment tool is preferred.
4. Worn Out Sprockets
Quick Summary:
- Remove sprocket key and screws
- Replace worn sprocket with a new sprocket
- Align both sprockets
- Place in sprocket key and tighten screws
Over time, the teeth on the sprockets of a go-kart will begin to wear down due to the friction of the chain driving the sprockets. Once this happens the teeth of the sprocket are not properly sized for the chain and as a result, the chain can completely disconnect from the sprocket.
How To Fix It:
You’ll need to keep a keen eye for wear on the sprockets and replace them as needed over the life of your kart. Unfortunately, there is no way to restore used sprockets, but you can very easily replace them. Essentially, you will just need to remove the worn out sprocket and replace it with a new one.
To maintain the same gear ratio you should make sure that the new sprocket has the same amount of teeth as the one that is being replaced. Here’s a guide on how to replace a sprocket.
- Remove the go-kart chain from the sprockets
- Remove the key that is holding the sprocket in place
- Remove the sprocket screws
- Slide the sprocket out of the shaft
- Slide the new sprocket onto the shaft
- Place key and tighten sprocket screws
5. Bent Go-Kart Frame
Quick Summary:
- Identify the section that needs to be straightened
- Carefully straighten section of the go-kart frame
- Seek help from an expert if required or replace frame if damaged beyond repair
This one is a little less obvious than the others on this list. A badly bent frame can lead to issues with your chain and for most racers, a bent frame is a reality that comes from collisions with other racers or barriers in the heat of battle.
Since the sprocket that drives the wheels of the go-kart is mounted to the axle (which is mounted to the frame); a bent frame can cause the axle and therefore the sprocket to be out of alignment. Once this happens, the chain can jump the sprocket and come right off.
How To Fix it:
Remedying this may be a difficult endeavour since repairing a bent frame can be an arduous and fruitless task. If you do repair the bent frame, take special care to ensure that the metalwork is properly performed due to the importance of the frame to the performance and safety of a kart.
You’ll definitely need to assess the area of the frame that is bent. Straightening a go-kart frame can be done, but you should know what you’re doing. In some scenarios you could even replace certain sections of the tubing.
You will just have to ensure that you don’t change the flex properties of your frame. When in doubt, bring your go-kart to a specialist who will be able to help you straighten your frame.
6. Deformed Axle
Quick Summary:
- Identify if the rear axle can be fixed or needs to be replaced with a new one
- Fix or replace the rear axle (remember to remove all the parts attached to it)
Much like a bent frame, an axle that’s been damaged in the heat of a race due to impact could lead to misalignment of the sprockets and cause the chain to fall off. This is because a bent go-kart axle could change the angle of your rear sprocket, ultimately causing them to be misaligned.
How to Fix It:
Unlike a frame, it’s much easier to replace and an axle. Alternatively, it can also be fixed, although you would need the proper tools for it. If you’re an aggressive racer or picked up a kart of someone that is an aggressive racer, you’re no doubt familiar with replacing axles due to the battle wounds of racing – especially over the long term.
If you’re looking to replace the entire rear axle, you can follow these steps:
- Remove wheel hubs, bearings, brake disk and sprocket from the axle
- Slide the bent axle out and replace with a new one that has the same specifications
- Reattach the wheel hubs, bearings, brake disk and sprocket.
