
Rajputana Customs does a one-off Triumph Bonneville with asymmetric headlights. This seems to be more for minimalist style rather than safety. There is only one rear tail light.

Another vertically stacked headlight on a motorcycle. Interesting but no reason given for the design choice.

2010 BMW S1000RR asymmetric headlights. No safety reason for the design, only that it is different. It supposedly saves some weight.
It was noted that several two-lamp experimental systems which were evaluated provided a significant subjective improvement over conventional systems in terms of light output. Two-lamp systems also have the benefit of providing lamp redundancy in case of a filament outage. (pg 15 of the report)
Several headlamps were used on more than one motorcycle to examine the perceived effectiveness as a function of the motorcycle application. Several two-lamp systems were used on the 350 cc motorcycle that provided a mid-beam or auxilliary low beam which augmented the conventional
low beam. Such mid-beam systems have been favorably evaluated for automotive headlighting
applications. (pp 67)
Although the issue of motorcycle conspicuity has not been addressed by this research program, some relief to the problem of maintaining a fully charged battery while operating a headlamp in daylight may be gained by the use of a low power (low to 20w) auxilliary headlamp which would provide intensity chiefly above the horizontal axis of the lamp, an area which is generally dealt with only by high beams. This auxilliary lamp, while chiefly intended to maximize daytime conspicuity while requiring limited power, could also be selectively used at night to provide improved illumination for large motorcycle roll angle cornering maneuvers. (pp 138)
While there is mention of asymmetric headlights the report references the asymmetric vs symmetric beam pattern of a single headlight.
- Before installing headlights or auxiliary lights, make sure they will not overload the motorcycle’s electrical system. It is best to have this equipment installed by an expert.
- Auxiliary lights can also be used as fog lights or to add to the lighting provided by the headlight’s low or high beams.
- They are available in various sizes and ranges.
- They should be installed as far away as possible from the main headlight and front position lights.
- They must be placed so that they make the motorcycle easier to see, but without blinding the other road users.
- Among the three types of lights available, LED lights only consume a fraction of the energy required to power halogen or high-intensity discharge (H.I.D.) lights for equivalent lighting.
- Auxiliary lights make the motorcycle more visible, but they do not increase the motorcyclist’s vision.
There is no mention of auxiliary headlight colours.
Rumar points out that motorcycles have a significant conspicuity disadvantage due to their smaller front cross-sectional area. This also leads to speed and distance estimation errors by other drivers. Rumar notes that a single headlamp does not provide adequate distance information and he suggests that three lamps, mounted in a triangular pattern, may assist in speed and distance estimation.
This observation by Rumar, combined with the recent studies of motorcycle accidents where most motorcycles had headlights illuminated in the daytime, indicates that single low-beam headlights might not be particularly effective as motorcycle DRLs. It is therefore necessary to consider the visual ergonomics of on-road situations when accessing the functional requirements for motorcycle DRLs.