HSD Gen 2

HSD Gen 2: The Basics

This article refers to HSD Gen 2 bikes.

Thank you for choosing Tern, and congratulations on purchasing your brand-new HSD! We’re delighted to be part of your journey. Since the HSD has undergone a comprehensive upgrade, we’re here to help you navigate its new functions. This article covers the basic functions of both the P and S-Class bikes, but if you prefer to watch the following explanation, you can watch the Owner Briefing videos for the P-Class and S-Class on YouTube.

1. Introduction

2. Adjusting the Bike Fit 

3. Important Bike Parts & Functions 

4. Bosch Smart System 

5. Securing Your Bike

6. Frame & Battery Keys 

7. Flat-Folding Your Bike 

8. Vertical Parking & Rolling 

9. Daily Riding Checklist 

10. Maintenance 

11. Accessories 

12. Ready for the ride? 


1. Introduction

The HSD Gen 2 includes P-Class and S-Class models. While both are equally cozy and cool to be seen around on, there are some important technical differences. So, please note: everything in the following will refer to both HSD classes unless otherwise indicated.


2. Adjusting the Bike Fit  

Your HSD comes with an adjustable stem and telescopic seatpost that help you find your optimal riding position.

2.1. Adjusting the Saddle Height  

The saddle height is adjusted by opening the quick-release lever, setting the seatpost to your preferred height, and closing the lever again to secure it. For your safety, please ensure that you stay within the minimum insertion point marked on the seatpost.

To adjust the tightness of the quick-release, open the lever, and then twist the clamp screw nut. The quick-release should be loose enough for you to be able to open the lever, but tight enough to prevent the seatpost from sliding down. Please remember to properly adjust and close the quick-release to prevent any risk of injury.

2.2. Adjusting the Andros Stem  

The HSD also comes with the Andros Stem, which helps you adjust the height, angle, and orientation of your handlebar. To adjust the Andros, raise one lever at a time, adjust the stem and handlebar to your desired position, and finally, close both levers firmly.

2.3. Adjusting the Suspension Seatpost  

For S-Class owners, your bike is equipped with the shock-absorbing Cane Creek Thudbuster Suspension Seatpost for an extra comfortable ride. To optimize your comfort, it’s possible to switch out the inner elastomer in the seatpost for one that’s more suitable for your body weight. For more information, visit Cane Creek’s website.


3. Important Bike Parts & Functions  

Your HSD comes with a shifter that allows you to control the speed and pedaling resistance. How you shift gears depends on which HSD model you have.

3.1. Changing Gears

3.1.1. HSD P10

The HSD P10 comes with a trigger shifter. To downshift to a lower gear, push the forward-facing shift lever paddle. To upshift to a higher gear, pull the rear-facing shift lever paddle.

3.1.2. HSD P5i

The HSD P5i comes with a twist shifter. To change gears, twist the shifter away from you to upshift, and toward you to downshift. What’s great about the P5i is that it comes with an internal gear hub, making it possible for you to shift gears at a standstill.

3.1.3. HSD S00

The HSD S00 has an Enviolo twist shifter with a continuously variable gear range. This means that the shifter has a spectrum instead of a fixed number of gears. For a lower ratio, twist the shifter away from you. For a higher ratio, twist the shifter toward you. The S00 also has an internal gear hub.

Regardless of which HSD model you have, we highly recommend that you change gears as you would on a regular bike—downshift before you come to a stop or ride up a steep hill, and upshift as you accelerate or ride downhill. This will help you maintain an efficient cadence and prevent premature wear on the drivetrain.

When shifting, remember to reduce the pressure on the pedal. If your bike has an internal gear hub, we recommend you stop pedaling when shifting.

3.2. Braking  

All HSD models have front and rear hydraulic disc brakes for excellent stopping power.

When looking at your handlebar from the rider’s position, the rear brake lever is on the right, and the front brake lever is on the left. In a few countries, this orientation may be reversed. Before going for a ride, we recommend double-checking each lever separately just to be sure.

Please apply even pressure to both brake levers when stopping. Braking suddenly can result in dangerous situations, particularly in wet or slippery conditions.

Due to their heavy use, brake pads may be the first components of your HSD that you need to replace. So, keep a good eye on your brake pads, especially if you regularly make steep descents.

3.3. Adjusting the Suspension Fork  

Your HSD comes with a shock-absorbing Suntour front suspension fork that has two adjusters: a Speed Lock adjuster and a Preload adjuster.

To enable suspension, turn the Speed Lock adjuster to the open position. To disable suspension, turn the Speed Lock adjuster to the lock position. The Preload adjuster lets you adjust the hardness or softness of your ride. Turn the Preload adjuster clockwise for a harder ride or turn it counter-clockwise for a softer one.


4. Bosch Smart System

4.1. The HSD is a Pedelec  

Before you venture out into the world with your HSD, we’d like to remind you that the HSD is a pedal-assisted electric bicycle—pedelec for short. This means that the Bosch motor will only provide power while you pedal. The motor will stop providing power once your local speed limit has been reached.

4.2. Bosch Smart System Basics  

The HSD Gen 2 is outfitted with the Bosch Smart System that links the motor, display, battery, control unit, and the eBike Flow app together.

4.3. LED Remote  

Your HSD comes with the LED Remote, which controls your bike's motor system and display, views your current battery charge level, connects your bike to the eBike Flow app, and more.

4.3.1. Turning the Bike On/Off  

To turn the motor system on and off, press the power button on the LED Remote. The system will automatically turn itself off if you don’t move the bike or press any buttons on the LED Remote for 10 minutes. It’s best to turn it on and off when standing next to or straddling the bike. Please never do it while you’re applying pressure to the pedals.

4.3.2. Assist Levels  

You can select how much assistance the motor provides at any given time during your ride.

To switch between the assistance levels—Eco, Tour, Auto, and Turbo—you can press the plus (+) or minus (-) button on the LED Remote. When you switch between assist levels, the LED light on the right will change color to indicate which level you’re in. Green is for Eco, blue is for Tour, purple is for Auto, and red is for Turbo.

Auto is a new Bosch Smart System level that automatically adjusts how much assistance the motor provides based on your riding conditions.

4.4. Display  

4.4.1. P-Class Bikes  

The P-Class bikes come with a Bosch Intuvia 100 display, which has a simple layout and shows you all the essential information you need to know.

The display shows the battery level, speed, and your current e-assist level. To view more information, press the left and right arrow buttons on the LED remote. Sometimes, you may receive a notification about your e-bike system and road safety. After reading the notification, you can press the selection button on the LED remote to delete the message.

To remove the Intuvia display, turn it 45 degrees counterclockwise and pull it out. To insert it back, place it in the same spot and turn it clockwise until it engages.

4.4.2. S-Class Bikes  

S-Class bikes come with a Bosch Kiox 300 display, which is full of helpful information divided into different categories.

You can scroll through the categories by pressing the left and right arrow buttons on the LED remote to view details about your speed, trip, range, and more. If you’d like to see more information within each category, press the selection button.

You also may receive a notification about your e-bike system and road safety every now and then. To delete the notification, press the selection button on the LED remote after reading it. To remove the display, push it toward the rear of the bike until you can lift it.

Removing the display will also automatically lock the bike. To insert the display, align it with the display mount and gently push it down toward the rear of the bike while also pushing it in until it engages. Reinstalling the Kiox 300 will automatically unlock the bike and activate the motor system.

Safety Tip: To prevent theft or tampering, we highly recommend that riders remove their display when leaving their bike unattended.

4.5. Walk Assist  

The Bosch Smart System has a Walk Assist function that lets you push your bike with less effort. This feature comes especially in handy when you need to push your bike up a steep hill or ramp.

Before activating Walk Assist, always make sure the bike is in one of the four e-assist modes. If the motor system is set to “Off” you won’t be able to activate it. To activate Walk Assist, press the (-) button on the LED Remote for more than 1 second and keep it pressed. Then either walk the bike forward, push the bike backward, or tilt the bike sideways to engage this function. To stop using walk assist, just stop holding the (-) button and press the (+) button or wait for 10 seconds.

Good to know: The speed of this function depends on which gear you’re in. The higher the gear, the more Walk Assist you’ll get.

4.6. Integrated Lighting System  

4.6.1. P-Class Bikes  

The HSD P-Class bikes have an integrated lighting system that connects the front and rear lights to your e-bike system. To turn the lights on, slide the switch at the rear of your front light to the right and press the (+) button on your LED Remote for three seconds. To turn the lights off, press the (+) button again for three seconds. You don’t need to change the position of the switch on the rear of the front light.

4.6.2. S-Class Bikes  

S-Class bikes have an integrated lighting system that connects the front, rear, and brake lights to your e-bike system. The brake light system automatically turns on whenever you turn the motor system on, and the brake lights will be activated when you squeeze the brakes. To turn the front light on and off, press the light bulb icon on the Light Controller on the left-hand side of the handlebar. To switch between high and low beams on your front light, press the lamp icon on your right-hand side.

Safety Tip: Always keep your lights on while riding, and adjust the front light beam angle downward to avoid blinding oncoming traffic.

4.7. Battery  

Your HSD bike includes a Bosch battery and a Bosch battery charger. It is possible to charge the battery either on or off the bike.

Safety Tip: Before you charge the battery, always make sure the motor system is turned off, and the battery is completely dry. If you’re charging it on the bike, also ensure the bike is placed on a fireproof surface.

4.7.1. Charging the battery ON the bike  

To charge the battery on the bike, open the rubber lid on the top tube, plug the connector into the socket, and connect the connector to an electric outlet.

4.7.2. Charging the battery OFF the bike  

To charge the battery off the bike, insert the key into the lock, turn, lift, and pull out the battery. Once the battery is off the bike, plug the connector into the socket, and plug the charger into an electric outlet. To insert the battery, place it on the battery mount and push the battery until you hear a click.

Safety Tip: Please remember to always remove the key from the lock after inserting the battery to ensure the battery doesn’t get disconnected and that no one removes the battery when you’re not around. To learn more about (maintaining) your battery, download the eBike operating manual.

4.8. eBike Flow App

The eBike Flow app is the control center for the Bosch Smart System. You can use it to lock your bike, customize the motor’s performance and riding modes, install the latest software updates, and a lot more. Once you’ve downloaded the app, it will give you step-by-step instructions on how to connect it to your bike. For the latest updates, please refer to the Bosch eBike Systems website.


5. Securing Your Bike

Thanks to the Bosch Smart System, the HSD has safety features that will put your mind at ease after parking outside. While these features help prevent your bike from being stolen, they are not meant to replace a bike lock to secure the frame to something sturdy. To optimize safety and convenience, we highly recommend setting up the Bosch eBike Lock by activating it through the Bosch eBike Flow app.

Tip: After activating the following functions on the Flow app, we recommend checking the settings to make sure all security functions are turned on.

5.1. Activating the eBike Lock (P-Class)  

The P-Class bikes come only with the Bosch eBike Lock function.

Once the motor system has been activated, it will automatically lock itself when you manually turn the system off, don’t move the bike, or press any buttons for 10 minutes. If your bike ever gets stolen, the thief won’t be able to get any power assistance from the motor. Since the eBike Lock setup works through the eBike Flow app, your smartphone will function as the key to unlock your motor system. This means that you can’t turn the bike system on unless your phone is close by.

To stay connected, the eBike Flow app should be running in the background and the Bluetooth function should remain turned on.

5.2. Activating the eBike Lock & Alarm (S-Class)  

The S-Class bikes are equipped with the both the Bosch eBike Lock and eBike Alarm.

Once the motor system has been activated, it will automatically lock itself when you manually turn the system off, don’t move the bike, press any buttons for 10 minutes, or remove the Kiox display. If your bike ever gets stolen, an alarm will sound, a message will be sent to the connected phone, and you will be able to track your bike through the eBike Flow app. The thief won’t be able to get any power assistance from the motor.

Both the eBike Lock and Alarm are set up through the eBike Flow app, which makes your smartphone the key to your bike’s motor system. You can’t turn the system on unless your phone is nearby, the Flow app runs in the background, and the Bluetooth function is turned on.

Please be aware that you will be automatically subscribed to a 12-month free trial of Flow+ upon initial activation of the eBike Lock and Alarm. Flow+ is a subscription service for e-bikes that have the Bosch ConnectModule. After the free trial, Flow+ will be automatically renewed and you will have the choice between a yearly or monthly subscription. Please note that the subscription price varies per region.

You may cancel your subscription to Flow+ at any time, provided that you do so 24 hours before the current period ends. Canceling Flow+ will disable the eBike Alarm feature after the selected payment period or annual expiration date. For more information, please visit the Bosch website.

5.3. Lock the Frame Lock  

Your HSD has an Abus frame lock located at the top of the rear wheel. To lock the frame lock, turn the key and slide down the knob until you hear a click. Then pull the key out. Please keep in mind that you can't remove the key unless the frame lock is locked, so always make sure the lock is firmly closed before attempting to remove the key.

Tip: For extra security, you can purchase an Abus chain lock that securely connects the frame lock to a fixed object.


6. Frame & Battery Keys

The key for your Abus frame lock matches the one for your Bosch battery, so you can use the same key to remove the battery and (un)lock the Abus frame lock.

Your bike should come with two sets of keys. To be safe, we recommend emailing the number to yourself and registering your keys with Abus. In case they get lost or damaged, you can apply for a new set of keys using your key’s serial number, which is engraved on your keys.


7. Flat-Folding Your Bike

Your HSD is designed to be fun and functional. The HSD’s cockpit can be folded in such a way that it fits into cars and can be taken on public transport. It might take some practice, but once you’ve memorized the following steps, you’ll fold your HSD in no time.

  1. Open both Andros Stem levers.
  2. Angle the stem upward so that it’s in line with the handlepost.
  3. Properly close both Andros Stem levers.
  4. Rotate the handlebar 180°.
  5. Slide the security knob on the handlepost upward, and pull down the lever.
  6. Fold the handlepost down.
  7. Lower the saddle.

When you close and open the lever, be sure that the lever feels stiff—but not too stiff. The stiffness is just right if you need to firmly pull the lever to open it and feel some resistance when you close it with your hand. Not correctly closing or adjusting the lever can pose a risk of injury.


8. Vertical Parking & Rolling

Your HSD is not only easy to ride but also easy to store. Vertical Parking helps you fit your HSD in narrower spaces (including an elevator) and make room for other stuff. This is how you park and roll your HSD vertically:

  1. Stand on either side of your bike and hold the handlebar with both hands.
  2. Apply the rear brake and walk backward until the bike stands up. Don’t pull the bike backward—just focus on walking.
  3. Ensure that all of the contact points on the rear of the bike are in contact with the floor and that the bike is parked on a flat, even surface.
  4. To get your bike back on both wheels, hold the handlebars, apply the rear brake, and walk forward until the front wheel makes contact with the ground. For your safety, please do not catch the bike as it comes down, but just walk forward with control instead.

You can also roll your HSD when the bike is in a vertical position, but please make sure you’re not holding the rear brake when rolling the bike forward.


9. Daily Riding Checklist

Safety should always come first. To ensure that everything on your bike is secured and functioning properly, we recommend you do the daily ABCQ test to check your air pressure, brakes, chain, quick release, and more.


10. Maintenance

It’s important to perform regular maintenance to keep your HSD nice and rolling. Much basic maintenance can be done at home and takes little time. For a more complete overview, we recommend you watch our basic bike maintenance video.

10.1. Clean and Lubricate Your Chain

If your HSD has a chain, it’s important to clean and lubricate it regularly to ensure smooth movement. After applying the lubricant, please don’t forget to wipe off any excess.

10.2. Clean and Maintain Your Belt

If your bike has a belt drive, you’ll notice that it’s more durable than chains and requires relatively less maintenance. Nevertheless, it’s still important to clean the belt with water when it’s visibly dirty. You can check out our belt maintenance article for more information.

10.3. Check if Your Wheels Are Trued

Check if your wheels are trued (straight) by spinning them. See if there are any side-to-side motions and if the disc brake rotor is not rubbing against the brake pads. If you find anything worn or damaged, bring your bike to your dealer.

10.4. Check For Signs of Wear

Some of your bike’s parts will wear over time, with the tires, chain, and brake pads most likely needing to be replaced sooner than other parts. In case you need to replace any parts of your HSD, simply reach out to your Tern dealer directly.

10.5. Regular Service Check-Up

Your HSD will need to be serviced regularly; all bikes need a quick tune-up one month after use so your dealer can adjust cables and other key parts.

After the first tune-up, we recommend that you take some time to discuss a regular service schedule with your dealer. How often you’ll bring your bike back for service will depend on your riding frequency, typical load, weather conditions, road surfaces, and more.

We recommend you read our Maintenance Schedule article for more detailed information.


11. Accessories

The HSD is a tough everyday bike that is made to carry both passengers and cargo. The HSD’s accessories are varied in terms of size and use, and there are tons of ways you could configure your passenger and cargo setup.

11.1. Passenger-Carrying Accessories

You can carry one passenger on the rear rack of your HSD. Please keep in mind that the rear rack can support up to 80 kg (176 lbs), which includes your passenger, any rear rack accessories, and cargo. While there are so many ways to configure your passenger setup, we recommend that you follow our Passenger Guide for safe riding.

11.2. Cargo-Carrying Accessories

Choosing the right accessories to carry stuff largely depends on your specific needs. Since there are so many different options to choose from, we recommend you check out our Cargo Guide to find your best cargo setup.


12. Ready for the ride?

We hope that this list of basic information can help you get started. If you’d like to have support from fellow HSD riders, we invite you to join our Tern HSD Facebook Group, where you can share your experiences with other HSD enthusiasts. Happy e-biking!