Why are Surron e-motos so quiet? Yep, the electric motor! But it is also whisper quiet thanks to the belt on the primary drive. The primary drive reduces the gearing to a more manageable power delivery for the rear wheel. Unlike a chain, it doesn’t make a bunch of noise or require the same ongoing maintenance, but it isn’t simply a set-it-and-forget-it part of your bike, either.
Let’s look into why the primary drive belt on a Surron LBX is so important, why some riders actually choose to change the belt to a chain (even if it’s louder), and how to make the conversion (and what to do if something goes wrong!)
What is the Surron primary drive?
The Surron primary drive is the first stage in a reduction gearing system that delivers power to the rear wheel. From the factory, the Surron LBX has a belt-driven reduction system. The belt is the quiet option to a chain, which other manufacturers such as Talaria use.
If you’re from an ICE dirt bike background, the idea of a primary drive may be a strange concept. E-motos like the Surron LBX have a dual reduction gearing system. This is also the reason why you can have your rear chain much tighter than on ICE dirtbikes as the front sprocket is on the pivot point of the swing arm instead of on the engine, which would necessitate a lot more freeplay in the chain as the suspension moves through its travel. The LBX doesn’t need that.
Reduction gearing allows for smaller sprockets, which are more cost-efficient, lighter, and allow for more options for customization. It also changes the physics of the swingarm which, for many complicated science reasons, you as the rider feel as different behavior in the rear wheel over bumps and jumps. It isn’t magic, though, and it does still require maintenance.
When is the time to replace the primary drive belt?
It is time to replace the primary drive belt on a Surron when the belt starts slipping, showing signs of cracking or breaking, or if you notice worn teeth on the belt. It always pays to have a spare belt in your tool bag along with basic tools that will allow you to replace it mid-ride.
Don’t forget about the castle nut! This article explains how to make removing the castle nut easier. Think about getting yourself the GritShift multi-tool to make changing the belt much quicker.
When you’re replacing your primary drive belt, also look at the front sprocket (or pulley) and see if the teeth have been worn. This could contribute to a faster wearing belt, and it could be a good idea to replace this sprocket.
This video shows E-Moto Bros out riding when their belt stops working. This can give you a good indication of what to expect and what to look out for.
If you’re wondering if your belt may break, or want something stronger, it could be time to upgrade to a chain drive.
Surron LBX belt-to-chain conversion
Why would you want to swap your nice quiet belt for a noisy chain? Simple, less chance of it failing. Belts can snap, and they can get worn down. But, is changing the belt to a chain the best option for your riding style? Here are a few things to consider:
Belt primary drive (Surron LBX)
- Quiet when riding
- Max efficiency for power delivery
- Lighter than a chain
- Are susceptible to breaking if you ride hard
Chain primary drive (Surron LBX)
- Lower efficiency than a belt (chains are heavier)
- Noisy compared to a belt
- Much less chance of breaking when riding hard
In this video, Rusty explains about the chain drive sprockets he designed with the GritShift R&D team:
Which setup is better?
If you want the peace of mind of a strong primary drive and routinely ride hard, go with the chain. This is especially true if you love riding in the sand, mud, or anything else that can get caught up in a belt. For a more stealth mode and if you ride to enjoy the scenery, keep with the belt.
How to replace the Primary belt drive
Replacing the primary belt drive is a relatively straightforward process when you know what you’re doing. If you want a way to make things easier that doesn’t involve removing the rear swing arm, then watch this video:
These are the basic steps if you’re more of a reader:
- Place your Surron on a stand with the rear wheel off the ground.
- If you use footpeg support braces, remove the top footpeg bracket.
- Loosen motor mounts.
- Remove the castle nut and take out the jackshaft bolt. As you take out the jackshaft bolt, use a screwdriver or similar to feed through the jackshaft to keep everything in alignment.
- Remove the screwdriver, and carefully remove the jackshaft.
- Feed the belt around the jackshaft, replace the jackshaft loosely. Remember to also put the chain back on the sprocket.
- Feed the belt to the motor, don’t put it on the motor yet.
- Position the jackshaft carefully and feed in the jackshaft.
- Put the belt around the sprocket and the motor.
- Tension correctly.
- Tighten the motor mount bolts.
- Check everything is correctly tightened.
- Test ride and recheck.
How to convert belt to chain drive
The steps to convert the belt to a chain drive make for a relatively straightforward job, if you’re handy on the tools. Have a look at the instructions below, watch a video or 2, and see if it’s something you’ll want to give a go. If not, contact your local Surron dealer or independent shop to organize the conversion.
Step-by-step instructions
This list isn’t exhaustive, it’s to give you an understanding of what is involved.
- Undo the pulley nut.
- Remove the belt – cutting is the easiest way.
- Remove the belt pinion sprocket.
- Remove the chain via the master link and remove the rear wheel.
- Remove castle nut on the swing arm (the Gritshift multi-tool works the best for this)
- Unbolt the suspension from the swing arm
- Remove the hub that connects the primary to secondary drive
- Remove the key from the hub
- Replace with the new sprocket and replace the key
- Replace the gear
- Replace the pulley on the jackshaft with the new sprocket
- Fasten to the correct torque
- Wrap the chain around the jackshaft
- Replace the swingarm, jackshaft and jackshaft bolt
- Replace suspension
- Replace rear wheel
- Install chain around sprockets
- Check everything has been tightened correctly
- Test ride and recheck.
The E-Moto bros video I mentioned earlier goes through a great tutorial, here is where the installation starts:
Sur Ronster reviews his primary chain drive mod with the GritShift conversion kit. Watch his video here for some great entertainment!
Surron belt and chain tension: Important Information!
The biggest mistake most people make with their LBX’s primary is having the tension too tight. This can cause excess wear on your sprockets. Also, be aware some aftermarket motors have slightly different positioning. If you purchase a chain conversion kit, check if it is compatible with your motor.
Generally, you should have around ½-inch of upward travel in your chain from resting, when you press up near the sprocket. In other words, you should have around ½ inch of slack in your primary chain.
Where to get replacements for your belt or chain?
Easy! Jump onto our website GritShift.com, where you’ll find everything you need to maintain and improve your Surron.
Please watch this video before you buy a primary chain drive:
Rusty explains what the common issues are and how to fix them on a primary chain drive. This is helpful for both the GritShift-designed Heavy Hitter parts and other manufacturers’ drive chains.
Don’t forget we’re here to help, if you have any questions or what to check if you’re ordering the correct part, send us a message here. We’ll get back to you real quick during business hours. After hours and weekends, we’re out riding! See you out there!
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