I’m following a Toyota hatchback at Bosch’s Shiobara, Japan, proving ground with the adaptive cruise control set. My prototype Automatic Manual Transmission (AMT) equipped 2025 KTM Super Adventure S follows at a safe distance adjusting speed as the driver speeds up and slows down. This is nothing new; radar-based adaptive cruise control made it to production on the 2021 Multistrada V4 S, followed by several more models from Yamaha, Triumph, BMW, Kawasaki, and KTM. Many riders, including myself, have come to trust highly refined ACC systems when riding highways as a relaxing way to go with the flow.But then, the driver stops. Not slows; stops. I have my right hand on the center of the handlebar well away from the throttle and front brake, and I have purposely dug my toe onto the right footpeg so as to not be able to activate the rear brake. Sounds like a collision is imminent? Not so fast; this bike is equipped with Bosch’s next-gen ACC with stop-and-go functionality. Without any effort other than putting my foot down, the KTM stops on its own. Freaky.

I press a button on the left switch housing to confirm I would like to move again when the car does. I could have also cracked the throttle ever so slightly for a fraction of a second when the car moves, but I prefer to leave no doubt the bike is doing all the work and leave my right hand on the center of the handlebar. The white hatch ahead rolls away, and I smoothly follow. Stop-and-go traffic just got easier for those spending the coin on Bosch-equipped high-end motorcycles.Bosch’s latest Advanced Rider Assistance Systems (ARAS) can do some pretty amazing things using a second-generation front and rear radar that works in concert with Bosch’s ABS unit and the bike’s ECU, IMU, and dash. The new radar sensors are 30 percent more compact, are lighter, and use less power. A new chirp sequence and modulation for more precise measurements of distance, velocity, and angle while being able to distinguish between multiple vehicles. WIth this higher fidelity, Bosch was able to increase functions for comfort and safety that rely on radar information—six new functions to be exact. Some functions will be used actively, or turned on by the rider, and some wait behind the scenes to assist in emergency situations.

There are 1.2 million road traffic fatalities worldwide each year, and motorcycles make up 21 percent of those numbers. Bosch says that one in six motorcycle accidents can be prevented with radar-based assistance systems. That’s a potential 42,000 lives saved.Bosch set up a full day of riding in the closed confines of the Shiobara proving ground and on the roads around the facility to understand and test each system with specific tests to highlight each new function. Some systems were easy to see in action and trust immediately while others required you to really place your safety and trust in Bosch’s engineers and systems.Rear Distance Warning (RDW)Bosch’s new Rear Distance Warning uses the rear radar to scan behind the motorcycle and warn the rider when a vehicle is following too closely. Bosch’s ARAS Project Manager Thomas Maurer pointed out that each manufacturer will decide how they will display the warning on the dash, but our Kawasaki H2 SX test unit displayed a warning icon on the left top of the dash letting you know someone was too close on your six.It’s then up to you what to do about the situation: Change lanes or move your position in some way. Or drop a gear a leave ‘em with the H2′s centrifugal supercharger whistling the sweet, sweet music of compressing air. One solution is reasonable and safe, the other is just plain fun.

Either way the RDW system worked without issue and as advertised, giving you notice when you may be in danger.Rear Collision Warning (RCW)Similarly, Rear Collision Warning is a rear-facing radar safety system that is meant to warn an approaching vehicle behind you that a collision is imminent. The warning comes in the form of rear hazard lights or turn signals to get the following driver’s attention. While not the most mind-blowing function, it’s a potential lifesaver.

Riding Distance Assist (RDA)Riding Distance Assist is a user-selected front radar function with two modes, Sport and Comfort. RDA increases the rider’s safety net by decelerating the motorcycle to avoid a collision with the vehicle ahead. As you approach the vehicle ahead, the bike slows and then will maintain a safe and fairly large gap when the throttle is consistent. The rider can then override the system for situations such as passing by adding some throttle input. When this is done a red warning light illuminates signifying that RDA has been overridden and is not functioning. After several seconds of consistent throttle the RDA resets and once again becomes active. Both modes slow the bike the same rate, but Comfort is less sensitive to the rider’s wishes to override the deceleration or distance keeping, while Sport jumps forward with just a slight increase in throttle.

It was an interesting prospect to hold the throttle steady as you approached the slower-moving lead vehicle, but each and every time the bike slowed comfortably with a feeling that I would describe as a soft cushion. You have a moment of rebound as the system softly brakes and then increases the following distance. Comfort was my preferred setting as Sport is too sensitive and the slightest movement of the wrist overrides RDA.As I became more comfortable, I pushed and tried to find fault with the system. For several miles I held the throttle at a steady three-quarters throttle in third gear on a KTM Super Adventure S. An input that normally would result in speeds much faster than the 30-ish mph the lead vehicle plodded along at. RDA kept me at a consistent distance, smoothly applying the brakes and modulating fueling. The only way to fool the system was to take a ridiculous inside to outside line on a tight bend, steering the radar’s 60-degree field of view away from the van in front. Point is, you have to really try to get the radar not to do its part of the job.

I see RDA as a useful tool when the traffic ahead on a twisting road moves at inconsistent speeds and there might be the possibility of fatigue and slow reactions as those ahead constantly vary their speed.Group Ride Assist (GRA)Group Ride Assist is an extension of Adaptive Cruise Control (ACC) that adjusts the motorcycle speed and distance to the closest vehicle in a group. Current iterations of ACC struggle with group riding as the radar can only track one vehicle at a time. With the new radar system, Bosch is able to track multiple bikes and recognize the staggered formation commonly used in group riding. GRA recognizes the lead bike, but now bases speed and distance off of the staggered riders ahead.

Having personally experienced ACC locking onto the bike directly ahead in a staggered formation (but another layer forward) and pushing the bike past the staggered bike closest to you on the other side of the lane, GRA is a welcome evolution of ACC.During a 30-minute ride down the highway and backroads of Tochigi prefecture, GRA consistently held the speed and distance needed to ensure continuity in a group ride environment. No runaway throttle when the lead rider pulled ahead of the staggered rider, no inadvertent passing of the staggered rider. Effective, precise, and useful: all the things you’d want from a group ride cruise control system.Adaptive Cruise Control Stop Go (ACC SG)Now, the attention-getting (and highly useful) ACC SG. Also using the front radar system, the stop-and-go capability, the feature is another extension of standard ACC, that will automatically control the speed and distance from the vehicle ahead. But unlike current production motorcycle ACC systems in use at the moment that will stop functioning at 30 kph (about 19 mph), SG will actually work down to and include a full stop.To prevent unwanted or unexpected accelerations from a stop, SG requires the rider to introduce a confirmation that they would like to continue after stopping. This can be a slight roll on and release of the throttle or pressing of a button on the switch gear. Either input can be done while the bike is stopped and the vehicle has not moved yet, but after a set amount of time the confirmation will reset if the machine ahead does not move.

As already described, the system worked flawlessly and consistently in the amount of time we had to test. It does require the learning of a new skill however: timing when to put your feet down. At first you tend to step to the pavement too soon while the bike is still slightly moving, requiring a “double-hop” to get your footing on the asphalt. This could result in a tip-over for those thinking they have completely come to a stop. After two stops, I found the timing and was able to get my boots on the ground easily.In heavy stop-and-go traffic where lane-splitting is not legal, this will absolutely make a rider’s life easier and less frustrating. I expect this will be a feature on most top-shelf tourers and ADVs in short order.Emergency Brake Assist (EBA)As impressive as ACC SG was to experience, Bosch’s Emergency Brake Assist was the showstopper during this test. Using the front radar, the system will detect an emergency situation and actually boost the motorcycle’s brake pressure to maximize stopping power if the rider doesn’t or can’t apply full pressure. This system is always active in the background as a safety system, but it does require that the rider initiates braking. It will not activate the brakes autonomously.Bosch’s data has proven that many riders will under-brake or not apply enough brake pressure in emergency situations. EBA corrects that problem.

Our test required riding at a soccer ball-sized plastic foam target on an arm protruding from the side of a minivan. The van would be moving at 30 kph and we were asked to ride at the ball at 50–55 kph. As we approached a large red warning filled the dash, followed by a haptic rumble in the seat to get your attention that things are about to go wrong if you don’t act. We were instructed to hit the brakes after the seat vibration while aiming at the ball. Oh, and try not to apply the brakes fully. Right… Sounds easy.Turns out, it wasn’t. On the first go, the seat vibrated, and I grabbed a handful of front brake. I stopped in plenty of time, but I was pretty sure I did all of the work. Take two, I concentrated completely on only applying about half of the pressure I thought was needed. I held my breath, lightly squeezed on cue… And, voilà! The front brake lever moved on its own toward the grip and the bike slowed just as hard as I did the pass before.

Pass after pass, I reduced lever pressure with the bike applying optimal braking on its own. I even pushed the parameters, accelerating to 70 kph and waiting longer and longer to touch the brakes. Bosch’s EBA braked right up the limit of traction as I tried to skewer the soccer ball, stopping me short every time. By far the most impressive result of the day.You may not ever need EBA, but you’ll be glad it’s there if you do. It’s a system that I hope to see in production on all bikes in the future, not just those high-end models with all the rider aids and electronics.

As it is now, we look forward to seeing all of Bosch’s new ARAS features on forthcoming 2025 models. They make for a safer and more comfortable ride with minimal input or thought from the rider. Saving lives and preventing crashes is the goal of ARAS, and after experiencing these new systems, Bosch is ever closer to save those 42,000 riders who are lost each year.