Choosing between the COLIGHT Apex 3.5-inch and 4.5-inch motorcycle auxiliary lights is not simply about getting a larger light. Both models share the same optical design, deliver controlled low-beam illumination, and feature a distinctive dual-beam lighting system. The real differences come down to high-beam performance, light size, and brightness control.
For riders who prefer a compact setup and a slightly broader high-beam footprint, the Apex 3.5-inch is an excellent choice. Riders who prioritize long-range visibility, adjustable brightness, and a larger visual presence may prefer the Apex 4.5-inch.
Here's how they compare in real-world use.
1. What Do the Apex 3.5-Inch and 4.5-Inch Lights Have in Common?
Before comparing their differences, it's worth understanding what both Apex models offer.
TIR Optical Design for Controlled Beam Performance
Both Apex 3.5-inch and 4.5-inch auxiliary lights use a TIR optical design to shape and direct light into purposeful beam patterns.
Unlike auxiliary lights that simply spread light in multiple directions, the Apex lighting system is engineered to provide distinct low-beam and high-beam performance.
- Low Beam: A defined, flat cutoff line helps control light above the beam, reducing unwanted glare for oncoming road users when properly installed and aimed.
- High Beam: A focused beam provides additional forward visibility for darker roads and longer-distance riding.
- Combo Beam: High and low beams operate together, combining the controlled low-beam coverage with additional forward illumination.
Low-Beam Performance: Similar Coverage and Character
The Apex 3.5-inch and 4.5-inch deliver very similar low-beam performance.
Both provide a controlled low-beam pattern with a flat cutoff line, making them suitable for riders who want additional illumination without simply flooding the area above the beam.
For everyday riding, winding roads, and mixed traffic conditions, the low-beam performance is not the primary reason to choose one size over the other.
The more noticeable difference appears when switching to high beam.
2. Apex 3.5-Inch vs. 4.5-Inch: Real Beam Pattern Comparison
The most meaningful optical difference between these two models is their high-beam distribution.
Apex 3.5-Inch: A Slightly Broader High-Beam Footprint
The Apex 3.5-inch high beam produces a slightly broader concentrated light footprint.
Its illumination spreads more across the visible riding area, giving riders a wider-feeling distribution of forward light.
This makes the 3.5-inch an appealing option for riders who prefer a balance between focused illumination and broader coverage.
Apex 4.5-Inch: More Focused High Beam and Longer Reach
The Apex 4.5-inch high beam features a brighter, more concentrated central hotspot.
Rather than spreading its concentrated illumination as broadly as the 3.5-inch, the 4.5-inch places greater emphasis on forward intensity and long-range reach.
For riders frequently traveling on dark rural roads, open highways, or routes with limited ambient lighting, this difference can be particularly valuable.
Parking-Lot Beam Test: See the Difference
The following beam comparison uses actual parking-lot light-pattern testing to show how the two Apex sizes distribute their illumination.
What should riders look for?
- Low beam: Similar controlled illumination and cutoff characteristics.
- Apex 3.5-inch high beam: Slightly broader concentrated illumination.
- Apex 4.5-inch high beam: Brighter central hotspot with greater emphasis on long-range illumination.
These comparisons help illustrate the beam characteristics, although actual visibility also depends on mounting height, aiming angle, road conditions, and the motorcycle's existing headlight.
3. Brightness Control: One of the Biggest Reasons to Choose Apex 4.5-Inch
Both Apex models feature independently selectable lighting functions, including high beam, low beam, DRL, and strobe modes.
However, the Apex 4.5-inch offers an additional feature that many riders appreciate: four adjustable brightness levels for the main light.
| Feature | Apex 3.5-Inch | Apex 4.5-Inch |
|---|---|---|
| High beam | Yes | Yes |
| Low beam | Yes | Yes |
| DRL | Yes | Yes |
| Strobe modes | Yes | Yes |
| Main-light dimming | No | Yes |
| Brightness levels | Full output | 100%, 80%, 60%, 40% |
| Switch | 3-button | 4-button dimming version |
Why Does Adjustable Brightness Matter?
Not every riding environment requires maximum auxiliary-light output.
With the Apex 4.5-inch, riders can adjust their lighting intensity to suit different conditions:
- Dark, open roads: Use 100% output when additional forward illumination is needed.
- Winding or wooded roads: Lower output can help balance illumination with the surrounding environment.
- Mixed riding conditions: Adjust auxiliary-light intensity to complement the motorcycle's factory headlight.
- Personal lighting preferences: Fine-tune output instead of relying on a single brightness level.
Brightness adjustment gives riders greater control over their lighting setup. Important: Dimming does not replace correct aiming or responsible use of auxiliary lights. Always use appropriate lighting settings for traffic and road conditions.
4. Which Apex Size Fits Your Motorcycle Better?
The Apex 3.5-inch and 4.5-inch share a similar design language, but their physical size creates a different visual effect.
Apex 3.5-Inch: Compact and Purposeful
The Apex 3.5-inch is particularly appealing to riders who want powerful auxiliary lighting without a bulky installation. Its compact dimensions make it a practical option for motorcycles with limited mounting space or riders who prefer a more understated setup.
It also works well for riders who want to keep their front-end appearance clean and balanced.
Apex 4.5-Inch: Larger Presence for Adventure and Touring Bikes
The Apex 4.5-inch has a more substantial appearance, making it a natural visual match for many mid-size and large adventure motorcycles.
Its larger proportions can complement motorcycles such as:
- BMW R 1250 GS / R 1300 GS
- BMW R 1250 GS Adventure
- KTM 1290 / 1390 Super Adventure
- Triumph Tiger 1200
- Ducati Multistrada V4
- Honda Africa Twin
- Yamaha Super Ténéré 1200
These are examples of motorcycle styles that may visually suit the 4.5-inch size, not guaranteed fitments. Actual compatibility depends on the mounting location, bracket configuration, clearance, and motorcycle-specific installation requirements.
5. What's Included with COLIGHT Apex Motorcycle Lights?
Both Apex sizes are designed to provide a complete auxiliary-light installation package.
| Included Component | Purpose |
|---|---|
| Wiring harness | Power connection and lighting control |
| Two face masks | Customizable front appearance |
| Tube clamp brackets | Mounting support for compatible installation locations |
| Switch | Control of lighting functions |
The exact switch configuration should be confirmed on the selected product listing, especially when choosing the Apex 4.5-inch dimming version.
6. Apex 3.5-Inch vs. 4.5-Inch: Which One Should You Buy?
The best choice depends on what matters most to your riding experience.
| Choose Apex 3.5-Inch If… | Choose Apex 4.5-Inch If… |
|---|---|
| You prefer a compact auxiliary-light setup | You prefer a larger light with more visual presence |
| Your motorcycle has limited mounting space | Your motorcycle has room for larger auxiliary lights |
| You prefer a slightly broader high-beam footprint | You prioritize a concentrated hotspot and longer-range reach |
| You don't need adjustable brightness | You want four main-light brightness levels |
| You want a clean, understated installation | You want a substantial lighting upgrade for an ADV or touring bike |
Our Recommendation
The Apex 3.5-inch is a strong choice for riders who value compact size, controlled beam performance, and a balanced lighting setup.
The Apex 4.5-inch is especially attractive for riders who want more long-range emphasis and the flexibility to adjust brightness across different riding environments.
Neither model is simply a smaller or larger version of the same light. Their high-beam characteristics and control options give each size a distinct purpose.
Whichever size you choose, the COLIGHT Apex series combines purposeful optical design, versatile lighting functions, and a premium, rugged appearance into a well-engineered auxiliary-lighting system for motorcycles.
Frequently Asked Questions
Is the Apex 3.5-inch brighter than the Apex 4.5-inch?
Their low-beam performance is very similar. The main difference is high-beam distribution: the Apex 3.5-inch has a slightly broader concentrated footprint, while the Apex 4.5-inch emphasizes a brighter central hotspot and longer-range reach.
Can the Apex 4.5-inch adjust brightness?
Yes. The 4-button dimming version offers four main-light brightness levels: 100%, 80%, 60%, and 40%. The adjustment applies to the main light, not the DRL.
Can COLIGHT Apex lights work with HEX ezCAN?
The Apex lights can be modified and wired to work with HEX ezCAN. However, COLIGHT recommends using the included wiring harness for the intended lighting functions and a straightforward installation.
Please note: Wiring modifications, damaged harnesses, or electrical damage caused by an incompatible voltage or improper wiring are not covered by warranty. For example, a harness physically damaged during modification or a light damaged by an unsuitable electrical supply would not qualify for warranty coverage.
For the most reliable installation, use the supplied harness and follow the installation instructions.
Do the Apex 3.5-inch and 4.5-inch use the same optical design?
Yes. Both use a TIR optical design. Their most noticeable difference is the distribution of high-beam illumination rather than a completely different low-beam system.
Which Apex size is better for adventure motorcycles?
Both can work well on adventure motorcycles when properly mounted. The 3.5-inch is ideal for a more compact installation, while the 4.5-inch is appealing for larger motorcycles with sufficient mounting clearance and riders who value adjustable brightness.
Are the Apex lights suitable for everyday road riding?
They can be used as auxiliary lighting when installed, aimed, and operated in accordance with applicable local lighting regulations. Riders should use appropriate beam settings and avoid dazzling other road users.
Explore the COLIGHT Apex Series
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Installation Example: How to Upgrade a 2011 BMW R1200GS with 4.5-Inch Apex Auxiliary Lights
The right auxiliary light should do more than look good on your motorcycle. It should deliver the beam performance, control, and flexibility that make sense for the way you ride.
With the COLIGHT Apex series, you can choose the size that fits your motorcycle and your lighting priorities—without compromising the thoughtful design behind the system.