Mini bike enthusiasts are always looking for ways to enhance their rides, whether it’s for better performance or cost-effective solutions. One question that often pops up in forums and discussions is whether snowblower engines can be a viable option for powering mini bikes. With snowblower engines frequently available at reasonable prices, especially on platforms like eBay, the idea of using them for a mini bike project is tempting. But are they really suitable? Let’s delve into the pros and cons of using a snowblower engine on a mini bike.
Advantages of Using a Snowblower Engine on a Mini Bike
Several compelling reasons make snowblower engines attractive for mini bike applications.
Cost-Effectiveness
One of the most significant advantages is the cost. Snowblower engines, particularly used ones, are often available at much lower prices compared to dedicated mini bike engines. As forum user ezeerider pointed out, “I see tons of these snowblower engines on eBay going real cheap.” This price difference can make a project more budget-friendly, especially for those looking to build or modify a mini bike without breaking the bank.
Engine Availability and Low Usage
Snowblower engines are seasonally used, typically only during winter. This often translates to lower operating hours compared to engines used year-round. As texasfabguy mentions, “Most of them are low hours so that’s good.” Finding a used snowblower engine with minimal wear and tear is quite possible, offering a reliable power source for your mini bike.
Potential for Added Features
Some snowblower engines come equipped with features that can be beneficial for a mini bike. Bigrob highlights, “Another bonus is that a lot of snowblowers have a lighting coil on them!” A lighting coil can be a valuable addition, allowing for the installation of headlights and taillights on your mini bike, enhancing safety and visibility, especially for evening rides.
Challenges and Modifications Needed
Despite the advantages, using a snowblower engine on a mini bike isn’t always a straightforward swap. Several modifications and considerations are necessary.
Crankshaft and Clutch Compatibility
A crucial factor is the crankshaft. wwwdotgov warns, “Alot of the crankshafts output shafts are stepped or tapered.” Mini bike clutches require a straight, consistent shaft diameter. Larger snowblower engines, typically 8hp and above, often have a 1-inch diameter shaft, while standard mini bikes usually use 5/8-inch or 3/4-inch clutches. Adapting to a 1-inch shaft means sourcing a compatible clutch, as Clayon advises: “Usually motors that are 8hp and up have a 1 inch shaft therefore you will need to by a 1 inch bore clutch instead of the usual 5/8 inch and 3/4 inch mini bike clutches.” Alternatively, as texasfabguy suggests, “The big or tapered PTO shafts can be turned down to 3/4″ strait shaft so you can use a standard clutch on them.” However, this requires machining and adds to the complexity.
Carburetor and Throttle Adjustments
Snowblower engines are designed for cold weather operation, which often means they have adjustable carburetors to optimize performance in freezing temperatures. texasfabguy notes they have “adjustable carbs on most for cold weather.” While this isn’t necessarily a disadvantage, it might require some tuning for optimal performance in warmer conditions. Additionally, the throttle linkage and controls on a snowblower engine will likely need modification to integrate with a mini bike’s throttle system. Ezeerider inquired about carburetors, asking, “So do ya change out the carbs on these things? I imagine you need to take off the carb shrouding, and I read somewhere that the carbs that use the primer bulb aren’t worth a damn.” While stock carbs can work, performance enthusiasts like roccosbike suggest upgrades: “You can run a Mikuni or Tillotson, for performance they work the best.”
Engine Size and Frame Fit
Snowblower engines, especially larger horsepower models, can be physically bigger than typical mini bike engines. Ezeerider questioned, “Do ya think an 8hp Tec blower engine would fit in a standard mini bike frame?” Clayon rightly points out, “I can’t tell you if they will fit in a mini bike because each frame is different and has more/less clearance. You will have to measure, or ask around to see if anyone else has put a motor that size in the mini bike frame you have.” Careful measurements and potentially frame modifications might be necessary to accommodate a larger snowblower engine.
Performance Potential and Upgrades
Despite the necessary modifications, snowblower engines can offer excellent performance on a mini bike, sometimes even exceeding expectations.
Surprising Power
Roccosbike, who has experience with snowblower engines on mini bikes, states, “I dont have a problem using them and this one would surprise you as far as how good it runs.” He even showcased a Bonanza mini bike powered by a Simplicity snowblower engine, an HM80, demonstrating the feasibility and performance capability.
Alt text: Bonanza mini bike powered by a modified HM80 snowblower engine, showcasing a successful engine swap.
Performance Enhancements
For those seeking even more power, snowblower engines, particularly Tecumseh HM80 models, can be heavily modified for enhanced performance. Roccosbike shared a picture of a modified HM80 engine, stating, “Heres a pic of the billet rod lightened piston and welded reground cam by precision cams. You can make an HM80 BB Tecumseh ‘RUN’.”
Alt text: Close-up of performance parts for a Tecumseh HM80 snowblower engine, including billet rod, lightened piston, and custom camshaft, illustrating potential engine upgrades.
These modifications, including carburetor upgrades, performance cams, and internal enhancements, can transform a snowblower engine into a high-performance mini bike powerplant. As Gustavo notes, “If you have an original minibike engine with lets say a broken block due to a rod failure you can use a snowblower engine and just transfer the minibike correct parts over. Its worth it money wise and an advantage would be most snowblower engines have low hours on them.” This makes them a great base for both stock replacements and high-performance builds.
Conclusion
Using a snowblower engine on a mini bike presents both advantages and challenges. The cost savings and availability of low-hour engines are significant pros. However, modifications to the crankshaft, carburetor, and potentially the frame are necessary. Ultimately, as roccosbike concludes, “Basically you can make any of these engines run good, it just costs money. A snowblower engine is no different than a mini bike engine other than throttle set ups, shrouds and flywheels. The internals are the same.” With some mechanical know-how and willingness to adapt, a snowblower engine can be a powerful and cost-effective heart for your mini bike project. Whether you’re aiming for an affordable ride or a high-performance machine, exploring snowblower engines is definitely worth considering for your next mini bike build.
