The world's most in-depth and scientific reviews of outdoor gear

The Best Bike Light Review

A bright bike light doesn't just brighten up the road  it can significantly improve your odds of avoiding being hit by a car.
Wednesday June 18, 2014
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What's the best bike light? We combined extensive laboratory testing with a year of field testing in four U.S. cities to create the most comprehensive bike light review available. In order to identify the best products for specific applications we measured the beam pattern, brightness, portability and battery life for each one, and rode thousands of miles on crowded city streets, rural roads, and trails. The 20 contenders we tested are a selection of the most popular and highly regarded products on the market today. They range from powerful/heavy models that shine a super bright beam to inexpensive safety models with flashing/strobe effects to help cars see you. Read on to learn more about the results of our testing, our methodology, and our recommendations for the best products available today.

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We have contacted all of the companies in this current review and noted any upgrades in the reviews, if applicable. A complete review was performed in June 2014.

Best Overall Bike Light

Cygolite Expilion 800

Cygolite Expilion 800
Editors' Choice Award

(21% off)
at Amazon
See It

Wide, even beam pattern
Many blinking modes
Difficult to remove from handlebars

The Cygolite Expilion 800 was the best overall tested. The competition was tight, but the 800 edged ahead because of its bright beam and, more importantly, the quality of that beam. The NiteRider Lumina 55 was just behind because it cast a more tunnel-like beam to the Expilion's broad, even beam. The one downside to the Expilion is that it is noticeably more difficult to remove than the Lumina series. It also costs a bit more. If you are looking for a little more value, and a product that is easier to remove, we strongly recommend considering the Lumina 550. One note, the Lumina scored almost identically to its more expensive sibling, the NiteRider Lumina 700.

The Expilion 800 has been discontinued and replaced by the new Cygolite Expilion 850. They both look similar, but the latest version features 50 more lumens and supposedly has a wider beam. We are currently in the process of testing the 850.

Best Bang for the Buck

Cygolite Metro 360

Best Buy Award

(18% off)
at Amazon
See It

Great value
Bright beam
Beam is not as even or broad as other bright lights

There is really no contest here: of all the contestants that cost $60 or less, the Cygolite Metro 360 was the only one with both a bright light and good beam quality. No, the beam quality is not nearly on par with the Cygolite Expilion 800. However, it delivers a beam almost as far, has a slightly better battery life score, and a street price of $45-60 compared to $100-140 for the 800. We toyed with the idea of giving a Best Buy award to the best $5-20 product. After all, many people want a light just to "be legal" while riding at night. However, all of the sub $20 products scored so low in beam quality and brightness, we just can not recommend them.

Top Pick Award for Mountain Biking

NiteRider Pro 1800

Top Pick Award

(36% off)
at Amazon
See It

Great beam distance and quality
Lasts five hours in high mode
Very heavy
Expensive and time-consuming to install and remove

Riding around with a very bright light that has a long battery life and a near perfect beam pattern is a true pleasure. The NiteRider Pro 1800 is by far the best mountain bike model we've tested…if you want a light for mountain biking look no further. This thing brightens up the night better than one of your car's headlamps!! However, unless you rarely remove a light from your bike, this is a very poor choice for commuting because it's the largest, heaviest, and most difficult to install of all sixteen contestants tested. For many people, this is only suited for off-road use.

Top Pick Award for Helmet

Light & Motion Vis 360 Pro

Top Pick Award

(25% off)
at REI
See It

Helmet mount allows you to point light where you want it
Front side light
Built-in tail light
Long battery life
Fast attachment
Very convenient
Beam is not as bright/wide/even as some handlebar lights
Helmet mount not for everyone
Can't turn off side lights

Of all the portable designs tested, our testers agree that the Light and Motion Vis 360+ made them feel the safest. This AMAZING helmet mount product lets you point the beam where you want, which is incredibly useful because you can see around corners, find street signs and house numbers, and shine it at oncoming and turning cars so they know where you are. The design also has two yellow side beams and a built-in red tail light…360 degree visibility!! To boot, it's compact, lightweight, very quick to install and remove, and its battery lasts twice as long as the Lumina 500's. If you are open to trying out a helmet mount product we highly recommend the Vis 360+ for both commuting and mountain biking.

Top Pick Award for Ultralight Safety Light

Knog Blinder MOB The Face

Knog Blinder 4 Standard
Top Pick Award

$45 List
List Price
See It

Very wide, eye-catching beam
Integrated handlebar mount
USB rechargeable battery
Small on/off button is hard to press
Short maximum beam distance

The Knog Blinder MOB The Face blows all other ultralight models out of the water with its wide, even beam, small, sleek, and compact design, tool-less attached mount and rechargeable battery with an integrated USB port with a 3.6 hour runtime on high, steady mode. Like all budget safety models, our testers mostly used this product on flashing mode because it caught the attention of drivers best (and much better than other small lights). On flashing mode the battery lasts nearly 7 hours! We found the Blinder to be by far the best product under $45. Whether you're an occasional rider, a dedicated commuter, or a road cyclist we highly recommend this as a small safety light.

Analysis and Test Results


As cyclists are a broad and diverse group, so are their needs in a bike light. You might require something that just satisfies minimum requirements to avoid paying a fine while riding well lit city streets, or you might have a habit of running your favorite mountain bike trail in pitch darkness and need something to illuminate every tree root well ahead. Whatever your needs, use the chart below to find the product that will work best for you in terms of performance and price.

As you can see, the products we tested follow a classic upward arc that indicates at the lower end of the price range, a little bit more money can buy you a lot more performance, but at the high end the performance gains come at a higher cost. For example, the NiteRider Pro 1800 comes out a few points ahead of its closest competitor in overall score, but at an over $200 higher price tag. For more modest budgets, there are a range of other award winners from $45 to $140, such as the Knog Blinder MOB The Face and Cygolite Expilion 800.

Safety: The #1 Reason to Invest in a Bike Light

If you bike on city streets, you already know the inherent risks of riding a bike in traffic with nothing to protect you from impact other than a helmet. Cars often don't see cyclists in the day, but at night, the risks are even worse. Much as flashing beams have been common on motorcycles for daytime, the use of flashing front and rear bike lights can reduce your risk of accident in daytime as well as night. Data from New York City and the National Highway Institute show that 70% of bike accidents are frontal collisions and that 72% of bike accidents occur at intersections. This data and our field testing experience in four U.S. cities indicate that a front bike light has a much greater influence on your safety than a rear one.

The graphics below suggest that wide and/or bright beams increase your visibility to oncoming motorists and reduce the probability of an accident. Some people consider helmet mounted models to be safer because you can point them at turning vehicles and they sit higher above the road (and thus may be more visible to oncoming motorists). However, we were unable to find any traffic accident data to validate this belief.

72% of bike accidents occur at intersections. Front  side  and rear lights make it easier for cars to see you from the side and rear (left graphic). A helmet mounted spotlight allows you to signal your presence to oncoming and turning vehicles (right graphic).
72% of bike accidents occur at intersections. Front, side, and rear lights make it easier for cars to see you from the side and rear (left graphic). A helmet mounted spotlight allows you to signal your presence to oncoming and turning vehicles (right graphic).

Our Testing Methodology

As you would expect, the biggest part of our testing process was using each product extensively in real-world conditions. These tests took place in four different cities in the U.S., over a wide range of streets and paths, including everything from heavily trafficked urban streets, to dark rural roads and mountain bike trails.

Beam distance photography and testing
Beam distance photography and testing

To augment our hands-on testing, we then photographed each contestant using the exact same camera settings to allow you to see the relative differences between competing models. You can see each one in our test here on our Beam Comparison page. Note the importance of beam pattern. Click on an image to zoom in.
Beam Distance Photos

Cygolite Metro 360
NiteRider Pro 1800

Lumens Are for Light Bulbs, not Bike Lights

Every product in this review includes a spec for lumens, but we recommend ignoring this because lumens measure light energy in any direction. While lumens are a good way to assess a household bulb, they are a poor measure of the quality of a focused beam. We believe our beam photos give you a better sense of the quality of the lens optics and relative brightness, than the manufacturer's lumen's specification.

This is the industrial light meter we used for our brightness tests
This is the industrial light meter we used for our brightness tests
We used an industrial light meter to measure brightness in Lux, and used that measurement to calculate the beam distance using the same ANSI standard used for flashlights and headlamp specifications.

We also photographed each model's beam pattern on a standard target to compare beam width and how evenly lit each beam was.

Left to right: Light and Motion Vis 360+, NiteRider Pro 1800
beam pattern.
beam pattern.

Lastly, we tested each contestants battery life, seeing how beam distance degrades as battery strength weakens, as well as overall battery life.

How to Choose the Correct Product for You

This review compares all types of bike lights. We group each one into one of the following categories, based on mount type:

Different Types Available

The type of design which will be right for you depends on your riding habits. After being out riding and testing, we split the selection of products tested into two main types:
  • Bright Beam — A bright beam is typical of most models costing more than $60. These products are heavier, but offer a bold wide beam that can fully illuminate a dark road or path in front of you on a moonless night. These products generally come with USB rechargeable batteries and are typically installed onto a handlebar with a quick release bracket for removal upon arrival at your destination.
  • Small Safety Lights — Small safety lights are compact and easy to store in your pack, but put out a relatively dim beam. These are suitable for those who ride on roads and paths that are fairly well lit at night by street lights. These small beams provide enough illumination to be legal when riding at night, but would be unsafe from our point of view to be bright enough to significantly illuminate a dark path on a moonless night.

The Knog Blinder 4 (left) is one of our favorite small safety lights. Compared to full-size lights like the NiteRider Lumnia at right  the Knog offers a fraction of the light output. But for riding on relatively well lit streets and paths  the Knog's flashing mode is visible to on-coming traffic  and offers the benefit of a very small  easy-to-use light  that is quick to take on/off the bike.
The Knog Blinder 4 (left) is one of our favorite small safety lights. Compared to full-size lights like the NiteRider Lumnia at right, the Knog offers a fraction of the light output. But for riding on relatively well lit streets and paths, the Knog's flashing mode is visible to on-coming traffic, and offers the benefit of a very small, easy-to-use light, that is quick to take on/off the bike.

Different Modes

Every contestant we tested offered a strobe mode which can be set to flash on and off. A flashing strobe increases your visibility to oncoming traffic, thus offering a key safety feature (especially for small safety lights whose beam may be too dim to stand out without the flashing mode). Just like motorcycle riders use a flashing beam to increase daytime riding safety, you can use a flashing beam both day and night to increase safety.

However, on a dark night when you are relying on the bike light to illuminate the road ahead, a flashing strobe is annoying.

The higher end bright beam models typically offer several levels of brightness and one or more flashing strobe mode.

Mounting Types

The normal mounting location is on the handlebar. However, a minority offer the option of mounting on a helmet as well. One model in our test, the Light and Motion VIS 360 is designed exclusively for helmet mount.
  • Handlebar Mount — The most popular and most versatile location. A quick release mechanism is provided to remove the light from the bike once you arrive at your destination.
  • Helmet Mount — Some consider a helmet mount to be the 'safest' and best for commuting because the beam is higher up, and thus easier to see from approaching vehicles. An ideal configuration for mountain biking is a combination of one light on the handlebar to illuminate the path ahead and one on your helmet that you easily focus on a turn.

Many headlamps mount to helmets with a cheap strap
A cheap fastening strap like this is often all you need to securely strap a headlamp to your bike helmet vents. This photo shows how to attach it. Results will vary based on the headlamp and helmet design.

Criteria for Evaluation

The chart below displays the total scores of each product from all the test metrics combined. Following the table, we discuss our results for the criteria used to evaluate each product. We describe methodology here.


The brightness is generally considered to be the most important criteria for safe nighttime riding. Whether your goal is to illuminate the road ahead, or simply to be seen by oncoming traffic, a bright, wide, evenly lit beam is ideal.

Maximum beam distance ranged from Knog Blinder 4 at a mere 9 meters to the NiteRider Pro 1800 with a distance of 172 meters.

The NiteRider Pro 1800 was the absolute brightest and the Expilion 800 was the second brightest. The amount your spend will have a direct correlation to beam distance. All the products we tested over $60 could manage to shine at least 100 meters distance. In the less than $60 category, only two contenders succeeded in shining the full length of a football field: the Metro 360, with a wide impressive beam shining 135 meters distance, and the Planet Bike Blaze 2 Watt which could shine a long distance, but the beam is so narrow that it was not competitive. Most of the low-cost competition selling for less than $60 shined less than 50 meters.

As you can see in the photo comparison below, the less expensive NiteRider 550 shines further, but the Cygolite 800 shines almost as far with a much broader and even beam pattern.

Beam Distance Photos

Cygolite Expilion 800
NiteRider Lumina 550

In the budget category, we think the Cygolite Metro 360 will hit a sweet spot of balancing reasonable price (Amazon sells it for under $50), and yet still very strong performance. The typical competitor in the $20-60 had a very narrow or dim beam, or both. Not so with the Cygolite 360, which produced a bright wide beam, blowing away the competitors in the under $60 street price range. The Planet Bike Blaze 2 watt is nearly the same cost as the Cygolite Metro, but was not nearly as bright and has a very narrow beam.

Beam Distance Photos

Planet Bike Blaze 2 watt
Cygolite Metro 360

For those who mostly ride in well lit areas, and are looking for a small and effective safety product, the ultralight Knog Blinder 4 was the clear winner. While it only scored a 6 out of 10 on beam quality, most of the low-cost competition scored much worse due to narrow beam or optical anomalies. While the Blinder 4 is not very bright (we scored it 2 out of 10 on brightness), the beam is wide, evenly lit, and in strobe mode presents a visible alert to oncoming traffic.

Beam Distance Photos

Knog Blinder 4
Seattle Sports Blazer

Beam Quality

Both for safety, and for seeing what's ahead of you, the best lens optics create a beam that is wide, evenly lit, and projects far into the distance. We measured each products beam diameter, distance, and photographed its beam pattern. The photos below should give you a sense of the variation in bike light optics.

Of all the contenders tested the NiteRider Pro 1800 has best overall beam pattern. It blows the rest away but also is by far the heaviest, most expensive at nearly $300, and the most time consuming to remove owing to a large, separate, battery pack. Based on our testing, we think most people looking for the best option for commuting will narrow it down to a showdown between the Cygolite Expilion 800, (available at Amazon for just over $100) and the NiteRider Lumina 550 (which sells at Amazon for under $80) (the NiteRider Lumina 700 would also be a contender to look at, but we think the Cygolite 800 outperforms it for about the same street price).

Beam Diameter and Pattern

Planet Bike Blaze 2 watt
NiteRider Lumina 700

Beam Diameter and Pattern

NiteRider Pro 1800
NiteRider Lumina 550


We scored portability on five variables:
  • ease of removal at bike rack
  • size and weight (can you fit it in a pocket?)
  • ease of install/moving from one bike to another
  • pivot (portable to different mount)
  • helmet compatible

We put most of the emphasis on the first two: how easy is the light to remove after locking your bike up at a rack and the size and weight. Many of these models cost over $100 and you will likely want to quickly remove it from your handlebar at the end of your commute.

Smaller size and lighter weight are universally desirable attributes. More weight makes it harder to pedal. Larger size (and heavier weight) are more burdensome to carry and store when not in use. The designs we tested here range from 1.3 oz. to 18 oz. and approximately 2 cu. in. to 23 cu. in.

The NiteRider Pro 1800 was the largest, heaviest and most time consuming to move. While it is the highest scoring overall because of its awesome beam quality and distance, it received a score of 1 for portability, so that (and its $300 price tag) could scare many commuters away.

Among top overall performers, the most portable were the Light and Motion Urban 700 which scored a 9 and the NiteRider Lumina 550 which scored an 8. The Urban 700 is one of the easiest design tested to move from bike to bike and install. It also comes in a relatively compact package for its beam power and easily slides into most pockets. The NiteRider is a little heavier but is among the easiest to slide on and off the bar mount. With a little practice, the NiteRider can easily be removed with one hand and has a smooth on and off glide. The Expilion 800 stumbled here: it takes much more hand strength than the competition to release; removing it requires a very firm push on the release tab, much more force than competing products required. After some practice, a person with stronger hands should have no problem. But if you hands are less strong, cold, or you are wearing gloves, removing the Cygolite 800 can be a struggle.

In the ultralight category, the NiteRider Lightning Bug 3.0 was the lightest, the Knog Blinder 4 was the most compact. That said, these didn't score any higher than some of the bigger lights because they require two hands to install and are slower to get on and off.

The Knog Blinder 4 (left) is one of our favorite small safety lights. Compared to full-size lights like the NiteRider Lumnia at right  the Knog offers a fraction of the light output. But for riding on relatively well lit streets and paths  the Knog's flashing mode is visible to on-coming traffic  and offers the benefit of a very small  easy-to-use light  that is quick to take on/off the bike.
The Knog Blinder 4 (left) is one of our favorite small safety lights. Compared to full-size lights like the NiteRider Lumnia at right, the Knog offers a fraction of the light output. But for riding on relatively well lit streets and paths, the Knog's flashing mode is visible to on-coming traffic, and offers the benefit of a very small, easy-to-use light, that is quick to take on/off the bike.

Mount Type Impacts Portability

The type of mount has a tremendous influence on portability because many commuters install and remove lights multiple times a day. Helmet mounted designs (like the Light and Motion Vis 360+) are the most convenient for commuting because they allow you to either remove the product from the helmet (if you lock your helmet with your bike) or keep it attached to your helmet, which requires zero additional effort compared to a handlebar mounted model.

Our favorite handlebar mount is found on the Light and Motion Urban and Nightrider Lumina series. The Light and Motion uses a tool-less adjustable rubber strap that's attached to the light; the low profile mount comes with you when you remove it. This has the advantage of being quick to transfer from one bike to another and it leaves your handlebar uncluttered when it's not attached.

The majority of the designs we tested slide onto a mount that is fixed to your handlebar. Some require a tool to install and are a pain to move from bike to bike. The NiteRider Lumina series went on easily and, once installed, allows it to easily slide on and off with one hand. An attached mount is best for mountain biking because it can be cinched very tight so that it stays in place through the extreme vibrations encountered while jumping and thumping off road.

For mountain biking, the need for long battery life and very high brightness force most good mountain bike model designs to use large external batteries that are relatively time consuming to install. For this reason the NiteRider Pro 1800 was the least portable tested. The table above lists various characteristics about each mount, including whether it is tool-less, attached, and/or can swivel.

The ability to swivel a handlebar mounted model can be tremendously useful for commuting because it allows you to illuminate street signs, find house numbers without stopping or turning your handlebar, and mount the it in atypical locations. Of all models tested, the Light and Motion Urban 700 has our favorite swivel mount because it spins 360 degrees.

Battery type also has a significant influence on ease of use. Batteries are usually either integrated into the design or mounted externally. USB rechargeable batteries are the most convenient because you can charge them just about anywhere, including from portable solar panels and battery banks, and you don't need to carry batteries or spend time buying them. The Knog Blinder 4 was the only product tested with a very convenient feature; a built in USB charger.

The Knog Blinder 4 has a rechargeable battery with an integrated USB port. No other product in our review is as convenient to charge or as compact.
The Knog Blinder 4 has a rechargeable battery with an integrated USB port. No other product in our review is as convenient to charge or as compact.
Some products, such as the NiteRider Lumina 550, have illuminated power buttons that make it easier to adjust levels on the go. This is a small feature that our testers wish were incorporated on every model.

Battery Life

We don't rely on manufacturer claims: we test battery life ourselves and plot maximum beam distance over time. You can read the full details of our testing methodology in the How We Test section of this review. For a deeper education in battery life, read our Headlamp Review and our article on Why Headlamp Claims are Deceptive.

There are three key considerations in battery life:
  • beam power over time
  • USB rechargeable vs. AAA and AA battery powered
  • regulated vs. non-regulated beams

Beam Power over Time

As you can see in the graph below, beam power is not consistent over time. Most lights are only their brightest for the first 1-5% of their overall run time. For the remaining 95-99% of the time, they are either slowly degrading, degrading fast and then holding steady, or a combination of the two. Keep this in mind when planning your night ride. Some products like the NightRider Pro 1800 lose their strength early but then give almost 5 hours of powerful illumination. Many others slowly degrade and then fall off a cliff after just over an hour.

It's not just about how long a light lasts for: more important is what amount of beam power you get over time.
It's not just about how long a light lasts for: more important is what amount of beam power you get over time.

Rechargeable vs. AAA and AA battery powered

When looking at our scores for battery life, you may be surprised how our Editors' Choice award winner the Expilion 800 scored only a 3 and the highest scoring for battery life were often the lowest scoring overall, like the Cateye HL-EL135. Keep in mind two things. First, the times are measured for the product in its brightest mode. The Expilion 800 only runs for 1.4 hours in bright mode but can be made to last much longer in low mode. Second, the models with the longest battery lives require replacing AA batteries. Yes, the Cateye lasted 55 hours in our test, but it did so with a very dim beam to start with and requires replacing batteries. Most commuters will prefer a USB rechargeable models because those products typically had the best beam performance, and even though they only last 1-2 hours in high mode, they are easy to recharge at the end of the day.

Of the rechargeable models, the NiteRider Pro 1800 with its massive external battery, lasted the longest at almost 5 hours and did so with an impressive 100 m of beam distance. Of the remaining USB rechargeable models, most lasted about 1.5 hours before either drastically degraded or shut off altogether.


A bright bike light doesn't just brighten up the road  it can significantly improve your odds of avoiding being hit by a car.
A bright bike light doesn't just brighten up the road, it can significantly improve your odds of avoiding being hit by a car.

While we can agree that a bike light is an essential bicycle accessory, it can be difficult to select the right one for you and your wheels. Top of the line products are rechargeable and will provide a very bright and high quality beam, making you stand out to other vehicles on the road in dark settings. However, they are also expensive. Obviously, it's hard to put a price tag on safety. Yet, if you ride on well-lit streets, you might not need the strongest, brightest light. Hopefully the results from our rigorous testing of the models in this review will help you trim down the selection to the top product for your needs.

Ask an Expert: Cameron Millard

Colorado transplant, Cameron Millard, moved from Maine ten years ago to live an active lifestyle in the Rocky Mountains. Embraced by a community of hard-core cyclists and surrounded by world-class mountain bike events such as the Leadville Trail 100, Colorado Trail Race (500+ miles), and the Vapor Trail 125, he took to the sport of endurance mountain biking and continues to cross those finish lines. For three years, he has raced the Vapor Trail 125 in Salida, Colorado; the 125 mile race has a 10:00 pm start mandating experience and skill that is limited by the glow of a bike light or two. In 2013, he rode his mountain bike over 560 miles with 70,000 feet of elevation gain along the Colorado Trail; the rules are simple- it is a self-supported race, no pre-arranged support except for post office mail drops, and no breaking laws along the way. More than six days spent biking this trail was life changing for Millard. Who better than Millard to offer expert advice on biking at night around town and while entered in endurance races?

Are your expectations for a bike light that you cruise around town with the same as what you will race with?
I am happy to cruise around town with some very basic lights, mostly for visibility from cars. Racing requires much better lighting systems that can illuminate a single track and remain bright all night.
For commuting and biking around town, a less expensive light system is sufficient. For racing and overnight rides, I recommend considering how long you will be out, how much light you will need (short summer nights and full moons), and what type of system will accommodate your needs. Be prepared to spend hundreds of dollars or more on a top racing setup.
Riding at night is awesome and the level of your interest/commitment/riding style will determine the kind of lighting you need.

How did you transition from racing in daylight to signing up for overnight bike races?
I've been night riding since high school, when rides would last until after dark. 24 hours of Moab was my first experience racing at night. The 24-hour format is kind of going away, but plenty of rides and racing still take place at night. Riding my bike at night is the best way to increase the progression of endurance riding; it makes sense to ride at night if you want to cover long distances.

With the experience you have of racing in the Vapor Trail races 3 times, how do you measure the risk of night riding?

There is a lot that can go wrong at night. Doing the Vapor Trail and Colorado Trail Race both involve a lot of night riding through technical terrain- this demands serious focus which can be a challenge, especially when you are accustomed to sleeping at night, not riding a bike for many miles at night. Its exhilarating to shred single track at night; it's a whole different experience than riding during the day. My riding partner and I did a lot of night riding this summer, mostly because it was convenient with our work schedules. Trails I have ridden a hundred times can be way more challenging at night; it is not without high risk.

Is it challenging to ride a long race that transitions from daylight to dark?
Good bike lights are critical to vision and mental acuity during the night. I combine good lights with transition sunglasses to help shift to lower light conditions. During longer events that start in day light, I would only have enough mental stamina to ride until 10 or 11 pm before I began to feel cross eyed. Excellent lighting is essential.

During full moon light, I have raced (uphill) without my lights on but you definitely need them when descending.

What is the difference between biking with a headlamp versus a bike light?

Bike lights can be configured to go on the handlebars and the helmet; the mounting systems are the distinguishing difference. Bike lights will typically be more powerful than standard headlamps and offer more focused or diffuse beam patterns depending on whether they are meant for the helmet or handlebars.

What are the most important features to look for in a bike light?
A bike light should be powerful with light quality that is appropriate for the terrain and conditions. I like a wider spread pattern on the handlebars and a focused light on the helmet. I value lightweight, durability, and simplicity for racing. There are many good light manufacturers. My preference is for Ay-Up lights for single night races and Dinotte lights for multi-day endurance racing. I've experimented with different systems: wearing a headlamp, finding a balance between weight and necessity which resulted in sub-par reliability, and have had experiences with lights going out during night races- that is a terrible situation to be in! You always want a back up light.
For mounting systems, avoid cheap plastic components. Rubber band style mounts are good.
Consider how often you will remove the mounting system- zip tie mounts are a hassle to remove.

Having at least 400 lumens is important, but so is run time, light quality, and beam pattern. I recommend trying a few different lights mounted on the handlebars, helmet, and both to find a combination that works for you.

Be sure to experiment with the lighting systems before committing to a race so that you know it suits the terrain, conditions, and your personal needs.

Chris McNamara, RJ Spurrier, and Max Neale