It is a feature built into the firmware. The surging is extra effort to get the wheel under you and prevent a nosedive if it senses you are starting to push it toward the limit. Pushback is a warning when you are gradually pushing the limit of speed and available power. Surging is a warning that you might be aggressively pushing that limit. You are more likely to get pushback on level ground, and surging when going uphill, over bumps, or anything else that might suddenly draw a lot of power.

If you are feeling that momentary surging, slipping feeling, back off.

If you lean to go forward and stand there like a passenger while the OW transports you, you won't recover from a nosedive (and maybe not feel pushback). If you keep centered over the wheel, and shift your weight only as much as needed to accelerate, and actively maintain your balance like you are surfing or snowboarding, there is a better chance that you will feel when something goes wrong and react fast enough to stay on the board.

Have you sold it yet? If the surge of power going over a bump causes it to shutoff, the controller is defective and it needs to go back to FM for repair. The next owner could easily experience a serious nosedive that is not their fault if it is not repaired.

The Onewheel can be an "electrically motorized board" which is allowed up to 20mph on streetswith limits under 35mph, and on sidewalks so long as they are ridden in a manner safe for pedestrians up to 15mph. Cities are allowed to make their own, more restrictive rules if they want.

The fangs attach using the screw points on the face of the bumper. The V1 bumper doesn't have screws there, only the Plus and XR bumpers do.

Make sure you read the manual, especially regarding pushback. It's fairly prominent on the XR, so if you aren't feeling the nose raise up at around 15mph you are definitely pushing it too hard. The OW balances by speeding up to get back under you when your weight moves forward, just as you would when balancing a broom on your hand. If you push it to fast or hard, the motor doesn't have any power left to accelerate more to keep the nose off the ground.

The other important thing is don't lean to go forward. Keep your head and shoulders above the wheel and use your hips and knees to move enough weight forward to move. You can jerk your hips back to make a correction a lot faster than you can jerk your head and shoulders back. This also makes it easier to put only as much weight ahead of the wheel as needed to move. If you lean your whole body forward, it will have to work harder to keep you balanced.

I wouldn't worry about selling someone a defective, dangerous board. It's only the footpad that is defective, and that is a $150 fix. They have been known to malfunction due to water damage, so if you have ridden exclusively on the beach, that is the likely cause. It doesn't have to have been submerged, Onewheels are often not very water resistant at all. It doesn't help that Future Motion has often posted videos of people riding in conditions that void the warranty. While it is fun to ride on the beach, salt water and electronics do not mix.

The heel lift is also key. Don't step off until the motor has disengaged.

It doesn't know you are nosediving until you are nosediving. It can be mostly fine (maybe you already ignored pushback) until you hit a bump or bit of resistance that suddenly shifts your weight forward too much for it to catch up with the little power remaining. It can sound an alarm at that point, but you will already be in the air.

Pushback happens early because it needs to have enough power to accelerate enough to lift the nose while also maintaining balance. That is your nosedive warning. After pushback, it cannot guarantee it will have enough power to keep you balanced in all conditions. Surging is a way to tell you to back off while it still has enough power to keep up with aggressive riding.

Requests for a nosedive warning sound like "Why hasn't FM implemented a warning to tell me when I am about to nosedive after I have ignored the other warnings?" If you had a nosedive and never felt pushback, then you need to work on riding in a way that keeps your head and shoulders centered over the wheel and not leaning out over the nose.

Not a "never before seen issue". Mine did the same thing after 4 days. I took it off the charger, and it would only stay on if it started up with an error like wrong orientation or contact with footpads. There were two cells out of balance, which may have caused a safety shutdown of some kind.

I didn't have it back for very long before cells started going out of balance again, to the point where one keeps going up until it triggers an overcharge error.

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