Cateye TL-LD1100 Review

We’re kicking off our bike light reviews with a classic. The CATEYE TL-LD1100 rear light from Cateye has been around for a few years and clearly the design has stood the test of time as it’s still as popular as ever.

This is for good reason. It features ten bright LEDs with six facing directly behind and two facing outwards at 90° from either side thus providing 180° visibility. 

It has numerous operating modes, long battery life and is robust enough to stand up to the harsh conditions of the daily commute.

CATEYE TL LD1100 Manufacturer Specifications

Dimension87.0 X 45.2 X 41.0mm
Weightapprox 116 grams (with bracket and batteries)
Light SourceRed LED X10
BatteryAA alkaline battery X2
RuntimeConstant mode: approx 50hrs 
Flashing mode: approx 100hrs 
Random mode: approx 100hrs 
Side to side mode: approx 100hrs 
Mount SizeSP-6, φ26.5-30.2mm

Cateye TL LD1100 Design

CATEYE TL-LD1100 rear bike light
       CATEYE TL-LD1100 rear bike light

The Cateye TL-LD1100 is a barrel-shaped light and has a good solid high-quality feel. The light with batteries weighs around 96g.

As it takes AA batteries rather than the smaller AAA, it is slightly bulkier than many other tail lights (though not excessively so).

In theory, with all other things equal, it should have either longer battery life and/or increased brightness compared to lights that use AAA batteries.

Two push buttons on the side control the operating modes. These are easy to operate with winter gloves but still require sufficient pressure, so accidental button pushes when the light is being carried in a bag are unlikely.

No tools are required to get at the batteries. They are accessed by twisting one end of the unit a quarter turn. It’s quite a tight fit and there’s a rubber seal so I don’t have any concerns about water getting in.

Over the last few weeks I’ve used the light in some heavy rain showers and not had any problems at all.

Cateye TL-LD1100 Light Bracket

Cateye TL-LD1100 Light Bracket

Most people would probably choose to mount the light on their seat post and the light comes supplied with a few mounting bracket options for this purpose.

Pretty much any size of the seat post is accommodated via the two different sized clamp rings, and mixing and matching with the grey plastic strips (each of different thickness) which fit snugly within them.  

A belt clip is also provided which provides further potential mounting options, for example to a pocket of a rucksack. Mounting to a rear rack is also possible with a rack mounting bracket(sold separately).

With all of the brackets, the light slots in and must be pushed down until a satisfying click is heard; otherwise the light is liable to hop out at the first pot hole.

The light is removed by pushing a small tab while pulling the light from the bracket. It can be a little fiddly at first but you soon get the hang of it.

TL-LD1100 Operating Modes

The light is operated by two buttons on the side. Each button independently controls the corresponding row of 5 LEDs. Pressing the button causes the row of LEDs to rotate between four different modes and off.

The first mode has all 5 LEDs in the row flashing in sync. The second mode has all LEDs permanently on. Readers of a certain age with dubious taste in TV of the eighties will recognise the third mode as the ‘Knight Rider’ pattern where the LED pattern sweeps from side to side.

The next mode causes the row of LEDs to flash in an eye-catching random pattern. Finally, pressing the button again turns the row of LEDs off.

As both rows can be set independently, a frankly ridiculous number of permutations are possible. My personal favorite is to have one row on constant while the other row flashes.

It’s often suggested that it’s less easy for motorists to judge distance when lights are flashing, however, the use of a flashing light can be effective at grabbing attention. This light gives the best of both worlds with this constant+flashing mode.

The video shows the modes much better than I can describe them:

I would have preferred it if one of the buttons was on/off and the other switches between modes. Even better if the last mode set was remembered as it would save a few button presses each time the light is used. It’s only a minor annoyance though and I’m sure others appreciate the flexibility of the current approach.

Cateye TL-LD1100 Beam Pattern & Brightness

The TL-LD1100 features Cateye’s patented “OptiCube™ Lens Technology”. The 6 LEDs pointing backwards are focused into quite an odd-looking beam which has an extremely bright square-shaped section in the center with an outer less bright circular region covering a wider area.

The region outside the beam still gets some light and with the 4 LEDs pointing out sideways, very good all-round visibility is achieved.

The brightest part of the beam is relatively narrow so it would be worth spending time when setting up the light to ensure the light is pointing at an appropriate angle to ensure drivers of both cars and lorries get the full ‘benefit’.

I think what works best is either to point it horizontally backwards or perhaps very slightly upwards. The actual brightness is also highly dependent on the type and age of the batteries used.

Cateye LD1100 Battery Life

Unless you’re only planning on using the light occasionally I would recommend a good set of NiMH rechargeable batteries with a rating of at least 2000mAh. For the battery life test, I used a set of 2900mAh batteries. (A test using the excellent Technoline BL-700 battery charger showed they actually had a capacity of around 2500mAh.)

With the light running in continuous mode on both rows, the batteries lasted for an impressive 48 hours before the light intensity had dropped to a glimmer.

For the second 24 hours though the light level had dropped to the point that most users would want to swap or recharge the batteries. Making use of the flashing modes on either or both of the rows gives longer battery life.

By measuring current levels in the various modes I determined that I should get about 30% longer battery life using my favorite constant+flashing mode – a very good result indeed.

If I was using the light every day for 1 hour per day, I would invest in a set of NiMH batteries (and a good charger such as the Technoline BL-700) and expect to charge them up about once a month to ensure the light is running with tip-top brightness.

Obviously that time would be scaled for different daily use. Given many NiMH batteries do not hold their charge over a long period of time, a standard set of Alkaline batteries would probably be better for the cyclists who only venture out into the night on the odd occasion and isn’t organized enough to recharge their batteries beforehand.


The Cateye TL LD1100 is a great light. It’s bright, has good all-round visibility, and is rugged and waterproof. It has numerous modes, the most useful of which being the constant+flashing mode.

I have no hesitation in recommending this bike light and it sets the benchmark against which rear bike lights will be measured in our upcoming reviews. It easily deserves a place on our best bike lights page.

Where to buy the Cateye TL-LD1100

Some options for where to buy the Cateye TL-LD1100 include HERE.

Look out for the light sets where the EL530 is bundled with the TL-LD1100. These can be significantly cheaper than buying the lights separately.