Mid-Drive vs Hub Motor eMTBs

Mid-Drive vs Hub Motor eMTBs

What Are Mid-Drive and Hub Motors on eMTBs?

Electric mountain bikes (eMTBs) use a motor and battery to assist the rider on climbs, trails, and rough terrain. There are two main eMTB motor types:

• Mid-drive motors – Located at the bike’s bottom bracket area and drive the crank to propel the bike.
• Hub drive motors – Contained inside the hub of one of the wheels, usually the front or rear. Directly drive the wheel.

Mid-drive and hub drive eMTB motors each have unique advantages for power delivery, performance, efficiency, and integration with the bike frame and components. Understanding how they differ helps select the best eMTB setup for your riding needs and style.

Below we’ll compare mid-drive vs hub drive eMTBs including leading models from Bosch, Shimano, Brose, Yamaha, Specialized, Giant and more.

Mid-Drive eMTB Advantages

Natural Ride Feel

Mid-drive motors deliver power through the drivetrain and gears. This provides a smoother, more seamless assist that feels like an extension of your natural pedaling.

Shifting gears seamlessly integrates the electric assistance. The power curves feel intuitive.

Hub drives tend to feel slightly more disconnected and jumpy by comparison.

Better Weight Distribution

With the motor weight centered within the frame rather than out in the wheels, mid-drive eMTBs handle more similarly to a normal bike.

The balanced front and rear weight distribution increases stability on descents, corners, and technical terrain. Hub drive eMTBs can feel front or rear heavy.

Enhanced Torque and Climbing

The gearing advantage of mid-drives allows them to maintain ample torque even on the steepest off-road climbs.

Applying motor force through the transmission multiplies it compared to direct drive. Mid-drives excel at challenging inclines and single track.

Increased Efficiency

Mid-drives make the most of each watt from the motor by utilizing the bike’s gear ratios. Less energy input achieves similar output vs hub motors.

Many mid-drives can match the performance of more powerful direct drive hubs while using a smaller, lighter motor.

Lower System Stress

With the propulsion spread across the drivetrain, individual components experience less force from the motor. Chains, wheels, etc. hold up better long term.

Mid-drive eMTBs have higher durability, with less wear on components that would need replacement.

Mid-Drive eMTB Disadvantages

Increased Cost

Mid-drive motors and systems are more expensive to manufacture than simple hub motors. This leads to a significantly higher retail cost for mid-drive eMTBs.

Budget buyers can get more features for their dollar with a hub drive model. Expect to pay $1000+ more for a mid-drive.

Greater Complexity

Integrating the motor into the drivetrain creates a more complex overall eBike system. This can intimidate some new owners when it comes to maintenance and issues.

Mid-drives often require professional diagnosis and service compared to simply swapping a hub motor wheel.

Potential for More Drivetrain Wear

While mid-drives spread out propulsion well, the added torque does put more stress on chains, cassettes, and chainrings versus a non-motorized bike.

Proper cleaning and maintenance is key to ensuring long component life. Chains wear quicker on mid-drive eMTBs.

Less Motor Cooling Ability

With the motor nestled in the frame, airflow is more limited compared to an open hub shell. Insufficient cooling can occur on longer climbs.

Mid-drives perform best for shorter distances or commutes rather than all-day backcountry adventures.

Hub Drive eMTB Advantages

Simple, Self-Contained Design

Hub drive motors consist of a simple, sealed self-contained unit integrated into the wheel. No connections to derailleurs, chains or gearing required.

This makes hub motors generally easier to manufacture, install, and maintain than mid-drives.

Better Water Resistance

With the motor safely sealed inside the hub away from the elements, hub drive eMTBs can better withstand riding in wet, muddy conditions.

The directly exposed mid-drive motor placement leaves it more vulnerable to ingress from splashes, streams, mud or rain.

Higher Top Speeds

Hub motors directly turn the wheel faster, allowing them to more easily achieve 28+ mph top speeds. They are not limited by gearing.

For flat land trail and commuting use where high speed is desirable, hub drives have the edge. Mid-drives typically max out at 20 mph.

Quick Wheel Swaps

If a hub motor does malfunction, the wheel can usually be quickly swapped out to regain riding. Much easier than disconnecting a mid-drive motor.

Carrying a spare hub drive wheel for longer trips provides peace of mind.

Hub Drive eMTB Disadvantages

Heavier Wheel Assembly

Concentrating all of the motor and battery weight in the hub makes for a very heavy wheel. This negates some of the nimble trail handling eMTBs are known for.

Less Efficient Power Delivery

Hub motors deliver power in a direct drive format through the wheel rather than through gearing. More rider input is required to achieve the desired level of assist.

The power delivery can feel slightly rougher and less seamless compared to a mid-drive system.

Uneven Weight Distribution

Adding so much weight to the rear wheel creates a lopsided weight distribution compared to the even distribution of a mid-drive.

Handling, cornering, and technical terrain agility suffer as a result since the normal weight balance is disrupted.

Excess Rear Wheel Wear

Combining a heavy hub motor in the rear wheel with eMTB riding forces leads to rapid wheel and tire wear.

The wheel/tire is more prone to needing truing or replacement sooner than a mid-drive or non-motorized MTB.

Less Capable on Inclines

Lacking gearing, hub motors lose their torque advantage on steep hills and single track. Difficult inclines require more rider effort compared to mid-drives.

Leading Mid-Drive eMTB Motors

Some top mid-drive electric MTB motor systems include:

Bosch – The Bosch Performance Line CX motor is the gold standard for refinement and reliability. Up to 75 Nm torque.

Shimano – Shimano Steps mid-drive is engineered for smooth, natural power assist suited to trails.

Brose – Compact yet powerful options like the Brose S-Mag deliver 90 Nm for impressive climbing.

Yamaha – The minimalist Yamaha PW-X motor prioritizes handling feel over power figures.

Fazua – Lightweight and removable Fazua mid-drive EV system focuses on simplicity and usability.

Specialized SL 1.1 – Custom motor designed by Specialized to perfectly complement their frames and riding style.

These motors from leading mid-drive specialists allow eMTB brands to optimize performance for their specific bikes.

Popular Hub Drive eMTB Motors

Among the major hub drive eMTB options are:

Bafang – Bafang is the most ubiquitous budget hub motor manufacturer, powering many lower-cost eMTBs.

Bosch – Bosch also offers capable hub drive motors like the Active Line as an alternative to their mid-drives.

Brose – Brose fill out their eMTB lineup with high quality hub drive motors matched to mid-drive models.

Shimano – Expanding their Steps line, Shimano produces reliable E6000 hub drive motors for eMTBs.

Benno – German eMTB brand Benno uses smooth Mahle hub motors tuned for their urban and trail models.

Sachs – Longtime hub drive specialist Sachs (owned by Mahle) supplies motors for several eMTB brands.

These major suppliers allow eMTB brands to pick reliable hub motors to match their frames and riding purpose.

Mid-Drive vs Hub Drive eMTB Comparison

Cross-Country Trail Riding

Best Motor: Mid-Drive

Cross-country trails favor balanced bike handling and reliable climbing torque over speed. Mid-drives deliver.

Downhill Bike Park Terrain

Best Motor: Mid-Drive or Hub Drive

Downhill requires stability. Mid-drive distribution helps, but hub motors allow speed. Either works.

Urban Commuting

Best Motor: Hub Drive

For flat city riding where high speeds help, direct drive hub motors can be ideal to commute quickly.

Bikepacking and Touring

Best Motor: Mid-Drive

Multi-day riding is best served by mid-drive efficiency and low maintenance needs.

Fat Bike Trail Conquering

Best Motor: Mid-Drive

The gear reduction of mid-drives greatly benefits scaling loose and technical trails on a fat bike’s big tires.

Cargo Hauling

Best Motor: Mid-Drive

Hauling heavy loads makes optimizing torque vital. Mid-drives use gearing efficiently even while loaded.

Are Mid-Drive eMTBs Better for Climbing?

Yes, mid-drive motors provide a distinct climbing advantage over hub drive:

More Torque

Mid-drives achieve greater torque, even at low speeds, by amplifying motor force through gearing. Direct drive hubs lack mechanical advantage.

Gear Range Optimization

Shifting allows keeping in an optimal gear for the conditions and terrain. Hubs lack flexible gearing.

Consistent Cadence

Gear changes maintain pedaling cadence in your power band despite grade changes. Hub motors lead to cadence fluctuations.

Traction

Centralized weight distribution increases rear wheel grip. Powering through the drivetrain reduces spinouts.

Efficiency

Every watt is maximized through gearing. Less effort is wasted compared to directly driving the wheel.

So mid-drives allow conquering steep, loose, and technical climbs much easier than hub drive eMTBs. The transmission leverage is a game changer.

Do Hub Drive eMTBs Wear Out Wheels Faster?

Yes, combining a heavy hub motor in the rear wheel with eMTB riding forces leads to accelerated wheel and tire wear.

Hub drive wheels experience:

• More Impact Forces – Rough terrain rapidly fatigues wheels with a hub motor’s added unsprung weight.
• More Torque Stress – Directly driving a wheel introduces tremendous torque forces from standstill.
• More Braking Load – Electric assist allows riding harder, necessitating more braking that wears wheels.
• More Power Output – Higher wattage hubs accelerate wear through greater power saturation.
• More Flats/Burps – The heavy wheel mass flexes tires more, causing punctures and air loss.

These factors add up to require truing, tensioning spokes, or replacing hub drive wheels and tires more frequently than mid-drive or non-motorized wheels.

Do eMTBs Require More Maintenance?

Some additional maintenance considerations apply to eMTBs versus standard mountain bikes:

• Motor: Periodic inspection, cleaning, lubing based on mfr. recommendations
• Chain: More frequent stretch checking and replacement from extra torque
• Tires: Monitor wear closely, especially on hub drive wheels
• Brakes: Maintain for heavier bike weight and higher speeds
• Bearings: Service wheel bearings earlier as they see more stress
• Wiring: Check connections stay tight and secure, away from rotors/snags
• Charging: Don’t over-charge battery, store at optimal volts when not riding
• Suspension: Tune forks and shocks for added system weight
• Storage: Keep away from weather extremes to protect electronics

While not drastically higher maintenance, the motor and battery do require some periodic care unique to eMTBs.

Choosing Electric MTB Conversion Kits

E-bike conversion kits allow adding electric assist to a standard pedal bike. For MTB conversions, consider:

• Motor type – Mid-drives retain mountain bike handling better than hub kits. Look for at least 500W power.
• Battery capacity – Enough for full days on the trail. 15-20Ah should suffice depending on range needs.
• Bike integration – Choose a kit matching your bike’s style and components to simplify install.
• Wheel size fit – Kits come for standard 26” MTB wheels or modern 27.5” and 29” sizes.
• Conversion complexity – Mid-drive kits require more dismantling than hub kits. Factor required tools and skills.
• Component stress – Heavier hub kits can overstress frames and wheels not designed for the forces.
• Cost – Entry-level kits start around $700 but more powerful, integrated options run up to $2500+.

Do your homework to end up with an electric MTB conversion optimal for your bike frame and riding needs.

Things to Know Before Getting an eMTB

E-MTBs ride differently than normal mountain bikes. Aspects to be aware of:

• Heavier weight – changes handling and trail feedback
• Faster speeds – require a greater safety margin
• Unique motor sounds – not a quiet experience like regular MTBs
• Learning power curves – takes adjustment to find optimal assist levels
• More planning – range limitation can dictate ride distances and locations
• Increased expenses – higher upfront cost and ongoing charging costs
• Different skills – finesse braking and weight management help vs muscling
• Mixed reception – not all trails or riders welcome electrified bikes
• Legal restrictions – many areas prohibit or limit eMTB access on natural surface trails

While very capable, aspects like weight, noise, and access limits give eMTBs a different experience than traditional off-road riding.

Types of eMTB Riding Restrictions

Many regions impose regulations and limitations around eMTB access on public trails:

• Motorized vehicle prohibition – Rules made before eMTB adoption often ban any motorized bikes from non-motorized trails.
• Specific eMTB bans – As their popularity increased, some areas enacted targeted eMTB restrictions on natural surface routes.
• Access limited to motorized trails – eMTBs may be restricted to ride motorbike and ATV routes rather than standard MTB trails.
• Limited to designated eMTB-only routes – Specific eMTB-permitted trails are created while banning them elsewhere.
• Conditional access exceptions – eMTBs may be granted limited conditional access, like on certain days or to disabled riders only.
• Speed limits enforced – eMTBs permitted but with rigid speed limits, like under 15 mph.
• Power caps – Only allowing lower powered eMTBs, such as under 750 watts.

Regulations continue to evolve. Check your local trail association, land managers, and jurisdictions for the latest eMTB access guidelines.

Are eMTBs Cheating? Mountain Bikers’ Perspectives

Many mountain bikers debate whether eMTBs constitute cheating or detract from a natural riding experience: