Chigee SR-1 Retrofit Bike Radar System

Blind spot warning systems, lane change assist, and rear-facing radar were long ingredients from that electronic delicatessen department on bikes, reserved mainly for expensive adventure bikes and luxury tourers. The Chigee SR-1 millimeter-wave radar system is meant to close exactly this gap. The small radar module can be operated independently of Chigee's own riding displays and only needs the two supplied warning lights positioned within the rider's field of view. Anyone who already owns a compatible AIO-5 or AIO-6 additionally gets graphical radar indicators on the display, adjustment options, and acoustic warnings via its speaker.

For our 1000PS Performance Check, the complete Chigee package migrated onto a BMW F 450 GS and then spent four days covering more than 1,000 kilometers of asphalt, gravel, and rougher Slovenian-Austrian backcountry. Alongside pure functionality, our focus was primarily on practical use: does the system generate lasting attention and greater safety, or does the visual warning simply get tuned out on the road?

Chigee packs no fewer than four assistance functions into the SR-1, and their logic becomes clear quickly in practice. BSD monitors the classic blind spot roughly ten meters behind the bike. AOA takes care, after an overtaking maneuver, of whether someone is still lurking to the rear side when merging back in. LCA works considerably further ahead and can take vehicles up to around 70 meters behind the bike into account, whereby it's not distance alone but especially relative speed that decides. Below 20 km/h, Chigee works by default with a risk horizon of roughly three seconds, between 20 and 60 km/h with five, and above that with up to ten seconds. RCW, in turn, focuses on what's happening directly behind the machine and detects the risk of a rear-end collision.

This distinction is particularly important, because "70 meters of radar range" might otherwise quickly sound like a permanent early-warning system. However, the SR-1 is not a Garmin Varia-style radar traffic display meant to announce every vehicle far behind as a matter of principle, but is primarily a blind spot and collision assistance system. The desire for an earlier warning stands opposed to the manufacturer's deliberately chosen design logic: to minimize false alarms from distant objects, the trigger impulse is controlled primarily via the combination of closing speed and relevance to the riding situation.

The BMW F 450 GS didn't make things overly easy for the extensive accessory package, since above the standard TFT there's no generous adventure-style crossbar on which displays, lights, or cameras could be hung to one's heart's content. That's why the editorial team mounted the AIO-6 riding display on the mirror and also placed the two SR-1 warning lights there, right within the direct peripheral field of view. The actual radar sits at the rear and, according to the manual, must be aligned horizontally, mounted between 30 and 100 centimeters high, and kept as free as possible from luggage, license plate holders, or other obstructions. Positive, negative, and a yellow ACC cable supply the system.

On the small BMW, the cable clutter could be tamed remarkably cleanly. Front and rear camera, AIO-6, radar sensor, and both warning lights could be routed without any adventurous loops, full steering lock was preserved, and even the rougher off-road sections loosened neither the mirror mount nor the glued or fastened components. For an accessory system that retrofits several electronic aids at once, the finished bike came across as surprisingly little like a rolling test lab.

Editorial note: During the test, the radar module was mistakenly mounted upside down. In principle, the mount allows for variable installation (upright or inverted) to adapt the system to a wide variety of bikes. In this case, during installation we simply didn't read the instruction manual thoroughly enough. However, this small faux pas had no negative effect on flawless operation.

On asphalt, it quickly became clear why radar-based blind spot warning systems have long been standard fare in cars. Cars, bikes, and trucks approaching from behind at an angle were reliably detected by the SR-1 in our test, and it signaled via the respective left or right warning light which side might become tight. However, timing was decisive. The system didn't report every road user who appeared somewhere in the distance, but became present above all when a vehicle actually moved into that zone where a lane change could end unpleasantly. Even longer rain spells didn't change this: despite a wet road surface, spray, and a permanently damp sensor, the SR-1 kept working without any noticeable dropouts and detected rearward traffic just as reliably as in dry conditions.

During the test, Gregor estimated the felt warning distance at about two to three meters behind the rear wheel. However, this is purely a subjective impression from the saddle and by no means a measured value or the technically defined warning zone. Chigee officially states around ten meters for BSD (Blind Spot Detection) and additionally works with relative speed and different warning algorithms. The seat-of-the-pants meter simply registered the warning consciously mainly when the following traffic was genuinely relevant and close. This is exactly where part of the strength lies: an assistance system that sounds the alarm constantly will eventually be ignored. One that reports predominantly at the right moment earns trust.

It doesn't go entirely without a few misfires into the shrubbery, though. As soon as we left the road and were traveling on narrower off-road sections, the SR-1 occasionally interpreted far-reaching branches or dense scrub as a relevant object. That's not dramatic, and thanks to the pleasantly dosed LEDs it wasn't bothersome either, but it nicely illustrates the limits of the technology: the radar simply doesn't know that the bush on a Slovenian gravel track definitely isn't planning a lane change.

This puts our experience right in the middle of user reports so far. While some reviews report no false alarms at all even after many rides and describe the system as extremely reliable, others mention occasional false reports in specific riding situations. So the SR-1 isn't infallible – however, in normal road traffic, its hit rate convinced us completely.

The two small orange indicator lights proved surprisingly well executed. In our setup they sat right next to the mirrors, remained clearly visible in peripheral vision, and still didn't burn into the retina. Chigee fits an ambient light sensor for this and automatically dims the brightness down when it gets dark. This manufacturer promise matches exactly our practical impression: visible, but not intrusive. Anyone using a compatible AIO-6 can, incidentally, leave out the external LEDs entirely and be warned exclusively via the display. We'd keep them anyway, because two small points of light on the mirror mount sit closer to the spot your gaze wanders to during a lane change anyway.

The SR-1, however, replaces neither the mirrors nor a shoulder check, and Chigee reasonably doesn't claim that either. Especially in dense traffic, the advantage arises one step earlier instead: even before you turn your head, you already know that something is present to the rear side. That can save that famous half second in which someone ahead suddenly hits the brakes while you're busy craning your neck.

We were able to experience a technically interesting additional function in practice – albeit completely unintentionally: if the SR-1 detects a vehicle approaching from behind at a critical speed, it's not only the rider warning that triggers. The radar module itself houses a bright light that suddenly begins flashing wildly to visually startle the traffic behind. According to the manual, the RCW zone lies at around ten meters and is triggered via a dynamic time-to-collision calculation.

Whether that actually prevents a real rear-end collision in an emergency can, of course, not be seriously assessed, but in keeping with the motto: if it doesn't help, it won't hurt either.

Perhaps the most important point for riders without a Chigee cockpit: the SR-1 doesn't need a Chigee riding display. Radar, wiring harness, and the two supplied warning lights already form a complete system. Using the current Chigee GO app, you can adjust sensitivity, activation speed, and other warning parameters among other things; firmware updates arrive via Bluetooth OTA. This makes the SR-1 particularly interesting for older bikes or cheaper models, where you'd like to retrofit modern safety assistance but don't necessarily want a second display on the handlebar right away.

A major point of criticism remains the audio. Without a display, there are only visual signals, and even combined with the AIO-5 or AIO-6, warning tones don't end up in the Bluetooth headset, but only through the built-in display speaker. For the next generation, this point tops our wish list: anyone riding at highway speed wearing a helmet and hearing protection naturally hears very little from a speaker on the handlebar.

On the F 450 GS, our AIO-6 was far more than pretty packaging for the radar warning. The 6-inch IPS display with 1280 × 720 pixels and up to 2,300 nits, dual-core A53 processor, and 4 GB of RAM brings above all Apple CarPlay and Android Auto to bikes whose manufacturers don't provide anything like that from the factory. That's exactly where, for Gregor, the greatest practical added value lies: pair your smartphone and set off immediately with Google Maps, music, or a compatible bike navigation app, without first having to learn an entirely new control universe. Beyond that, Chigee also supports, among other things, TPMS, OBD modules, cameras, BMW integration, and, of course, the SR-1.

During the on-road stages, the editorial team navigated exclusively via the AIO-6 with Google Maps. The system responded smoothly, remained easy to read, and could also be grasped quickly while riding. For off-road routes, things naturally depend on the smartphone app used; OsmAnd or Calimoto, for example, can be integrated into the CarPlay or Android Auto universe. On compatible BMWs, the AIO-6 can also be operated via a BMW quick-release module at the original navigation mount; depending on model and equipment, Wonder Wheel control or additional CAN integration is also possible.

Once the SR-1 is paired, the warning is visualized on the AIO-6. Sensibly, Chigee automatically deactivates the camera's visual blind spot detection in this case and relies fully on the millimeter-wave radar.

To clarify: on this trip, the editorial team did not use the complete Chigee XR-1 standalone system, which we already tested on NoPain's Ducati Hypermotard 698 Mono, but only the front and rear cameras in combination with the AIO-6. The two separately available cameras record at 1920 × 1080 pixels, HDR, and 60 fps; recordings are stored via a separate, fast microSD card. The recordings are controlled directly via the AIO-6 or via the Chigee GO app.

After more than 1,000 kilometers, no major weaknesses remain, but there are a few points worth knowing before purchase. For instance, the stated 70 meters is only the maximum detection range, not a permanent warning distance – anyone expecting a traffic scanner looking far to the rear might initially be irritated. In addition, off-road sections, dense vegetation, or objects brushing past can occasionally generate false reports.

Depending on the bike and wiring, longer cables may also be necessary. Anyone who owns several bikes, each with its own SR-1, and moves a single AIO display between them, must also keep in mind that the display can only be paired with one radar at a time. When switching bikes, the old radar therefore has to be deleted and the new one freshly paired.

However, the clearest functional criticism for us remains the missing transmission of acoustic radar warnings to the intercom. That's not a dealbreaker, since the mirror LEDs work very well. But a system that integrates so convincingly into the digital bike cockpit should, in the long run, also send its most important warning to where it's guaranteed to be noticed at 100 km/h: directly into the helmet.