How to Build a Motorized Lowrider Bike

Not everyone can turn a Chevy into a lowrider, but nearly anyone can turn their bike into a motorized lowrider bike. Installing a motorized bike engine makes for one mean ride, but most of these engines are made for 26-inch beach cruisers. As such, mounting a bike engine on a lowrider bike can be tricky because of the frame size and design of these bicycles. Thankfully, with a few modifications and specific parts, you'll be able to put together your dream lowrider.

Whether you’re a passionate lowrider fan or this is your first lowrider build, there are workarounds to installing an engine on your favorite bicycle. In this article, we’ll take a look at what you need to get a motorized lowrider bike up and running, restrictions to be aware of, and the proper assembly.

Choosing a Lowrider Bike

For the optimal motorized lowrider bike, you’ll first want to take into consideration the bicycle itself. Most lowrider bikes have 20-inch wheels, so the bike frame is closer to the ground and smaller in size than a lot of other bikes. You’ll want a bike with a frame that can hold a motor with no problems. Lowrider bikes like the Micargi Men’s Hero, Micargi Lowrider F4, and Micargi Men’s Famous have a 9-inch clearance in the center of their frames, as well as enough room between their spokes for a rear sprocket. They also have around 1.5-inch tubes on their frames, which means an engine kit can be properly installed on these bikes, and you won’t have to worry about space limitations for the motor itself. Of course, there are plenty of choices out there, so when you're looking for the right lowrider to motorize, here are the bike specs to keep in mind:

• The center of the frame should have a 9-inch clearance in order for the engine to fit.
• The frame should have at least 1.5-inch diameter tubes. You don't have much room in your frame, so mounting vibration motor mounts will not work here.
• The wheels will need to be at least 20 inches, as smaller wheels won't hold the weight of a rider and an engine.
• The wheels must have a spoke pattern that allows for the 9-bolt sprocket mount assembly that comes with engines kits.

Now of course, the term "lowrider" can be seen broadly. Some see it as a style and independent of wheel size, meaning they'll use 26-inch 144 spoke wheels, a banana seat, and whitewall tires. While this article focuses on 20-inch bikes, the same requirements are needed for any bike to ensure an engine fits.

Choosing Your Engine

The great thing about 2-stroke engines is that they're small, fast, and highly customizable — the way a lowrider engine should be. At around 8.5 to 9 inches, 2-stroke engines are especially ideal if you’re putting together a motorized lowrider bicycle. With 2-stroke bike engines, you’ll have three displacement (cc) options to choose from: 48cc, 66/80cc, or 80/100cc. Engine performance will vary slightly depending on this displacement, so it’s important to keep the differences in mind when choosing a 2-stroke engine for your motorized lowrider bicycle.

• 48cc 2-stroke engines run smoother and rev higher than 66/80cc 2-stroke engines while still delivering decent maximum speeds.
• 66/80cc 2-stroke engines are overall much faster than 48cc 2-stroke engines. They’re great options for those who plan on doing additional work on their lowrider bike after engine installation. 66/80cc engines are highly customizable and can be upgraded with high-performance parts that allow for faster and smoother rides.
• 100cc 2-stroke engines are the largest of the three and offer a lot of power. While the volume of air and fuel being pushed through a 100cc 2-stroke engine is greater, this engine type only has a single cylinder. This is beneficial because it is shorter compared to the 48cc and 66/80cc 2-stroke engines, which leads to an easier fit on the lowrider bike.

Considerations

Lowrider bikes have smaller frames and are closer to the ground than your average 26-inch beach cruiser or mountain bike. As such, you're going to notice some restrictions compared to motorizing a traditional bicycle.

 

Limited Muffler Options

When building a motorized lowrider bike, the ideal muffler will angle upward or horizontally. A muffler like the BBR Tuning High Performance F2 Thrust Exhaust Muffler is perfect for these applications because it sits around 4 inches above the motor, which is a great height for safe riding. A flexible muffler that can be positioned in different angles, like the BBR Tuning Flex Fit Poo Poo Motocross Muffler, is also a great option. This will allow you to bend the muffler to your liking so it’s not hanging low and dragging while you ride.

Unfortunately, mufflers like the Voodoo Muffler or the Street Poo Poo Muffler won't work, as they also hang too close to the ground when mounted on small frames. Expansion chambers will also hang low, though they can be used on motorized lowriders so long as you have at least three to four inches between itself and the ground.

Rethink High-Performance Parts

Optional high-performance add-ons can make an engine too large to even fit on your lowrider bicycle frame. For these builds, it’s best to keep bulky performance upgrades to a minimum. Now, if you're looking for a boost of power out of your motor, upgrading your carburetor to a speed carburetor is a great way to get some extra top end speed. Upgrading your electronic components and using a high performance CDI or an upgraded magneto will increase performance, too. These components are fairly small and won’t create unnecessary bulk for your motorized lowrider bicycle.

 

4-Stroke Engine Options Are Limited

Due to their larger, bulkier size, 4-stroke engines aren’t exactly ideal for putting together a lowrider motorized bicycle. That’s not to say it can’t be done, though. In fact, you should be able to install a rear-mounted 4-stroke engine like the BBR Tuning 38cc Lock-N-Load Friction Drive Bicycle Engine Kit with little to no hassle. Just keep in mind that anything larger and heavier could create a major imbalance on the back wheel.

What You Need to Build a Motorized Lowrider Bicycle

To assemble your motorized lowrider bike, you’ll need to make sure you have the correct components. You’ll need a few specific parts to get your engine installed onto your motorized bike with no problems.

• A standard 2-Stroke bike engine kit or 38cc 4-stroke friction drive engine kit. Larger 4-stroke engines like a 49cc friction drive engine and dual start engines like the BBR Tuning Bullet Train are too heavy and wide to fit onto lowrider bikes comfortably.
• A cylinder head with an angled spark plug port. This will ensure that your engine’s spark plug is offset at an angle rather than straight up, which would likely cause fitting issues with the bike frame.
• A short, angled, or flexible muffler. Standard mufflers could potentially drag on a motorized lowrider bicycle. Thankfully, these alternate options will provide the necessary clearance for the muffler.
• A small rear sprocket like a 36-tooth sprocket is more ideal than a larger sprocket due to the smaller size of the lowrider bike’s wheels.

Once you have all of the necessary parts, you can begin motorizing your lowrider bike. The installation is going to be virtually the same as it would with any bike:

• Mount the engine and tank to the frame.
• Mount the rear sprocket to the rear wheel.
• Install the throttle and clutch assemblies, wire up, and you're ready for fuel.

It's worth noting that most engine kit components are made with 26-inch bikes in mind. As a result, when you're installing the engine, there are a few things you're going to need to consider regarding sizing:

• The distance from your rear wheel to your engine is significantly shorter than that of the 26-inch bikes these engine kit chains are made for. You will need to remove multiple links in order to size the chain for a motorized lowrider bicycle.
• The distance from your handlebars and the engine is much shorter than what the engine's throttle and clutch cables were originally designed for. You will need to shorten each cable or wrap them and tie them to your frame in a way that won't interfere with your wheels.
  • Be sure to keep an eye on your wires during installation, tying them to your frame as needed to ensure safety.
• If you plan on upgrading your carburetor, you will likely need to use an offset manifold when doing so. This manifold will offset the carburetor so that it can sit out from the motor instead of right behind it, where there's no room for upgraded carburetors and air filters.

Despite a few differences and adjustments, installation should be fairly similar to putting together a standard motorized bike. So if you need a reference point, you can use our 2-stroke engine installation video as a general guide.

 

Riding Your Motorized Lowrider Bike

It’s a little trickier than building a regular motorized bike, but installing an engine on a lowrider bike is certainly doable. If you’re a lowrider enthusiast and you want that slick, old school build, you can certainly pull it off. You may need a few custom parts, and you might need to keep the performance upgrades to the bare minimum, but it’s a small price to pay for a stylish motorized bike. By following the steps outlined in this article, you’ll be riding your very own motorized lowrider bike in no time!