Serfas TSL-500 True 500 Lumen Headlight Review


Serfas TSL-500 True 500 LumensSerfas TSL-500 True 500 Lumen headlight is a really slick piece of cycling equipment.  At 500 Lumens, the Serfas True 500 really puts out some serious light.  The bar mounting bracket has a wide range of size adjustments, so it will fit on just about any handlebar.  Once in place, the light doesn’t move around.

The Serfas TSL-500 is also USB chargeable, so using it as commuter light is perfect.  When you get to work, simply plug it into a USB with the provided power cord and you are good to go.

I also found that the light works for trail running.  The Serfas light is the perfect size for a handheld and will certainly be much brighter than most flashlights at that size.  The only drawback is the light isn’t really designed for this type of use and the unit does get hot.

The Serfas TSL-500 puts out a wide enough beam to take up one lane on the highway.  I was able to get about a 1-2 second reaction time warning at 35mph from road debris and probably 2-4 second warning at 18-20mph.  This gives you plenty of time to swerve around the obstacle.  I am sure a 1000 Lumen light would give you even more time, but for most people 500 lumens is all they would ever need.  If I was mountain biking I would probably want something more powerful or combine it with another light for total nighttime coverage on the trails.

The Serfas TSL-500 comes with a nice box with foam padding, so once the days are longer, you can store it until needed again.

Here is a quick overview

  • Produces over 500 Lumens in Overdrive mode
  • USB Rechargeable, includes Wall Charger
  • Removable Lithium Ion Battery
  • Battery Charge Indicator
  • Helmet Mount Included
  • Tool Free installation
  • Up to 1.75 Hours Runtime in Overdrive Mode
  • Additional Batteries available for longer night rides

Now for the fun stuff.

The Serfas TSL-500 weighs about 150 grams with the bracket and has 5 light output settings

  • Over Drive (500 Lumens) 1.75 hours
  • High (325 Lumens) 2.5 hours
  • Standard (200 Lumens) 4 hours
  • Low (100 Lumens) 8 hours
  • Flashing 4.5 hours

I found the Over Drive to be the optimal setting when cycling at high speed.  I also found that when low battery indicator starts to flash orange/red, switching to the High setting extended the battery life and provided enough useful light to continue at speed.  When riding at dusk, I would typically start off with the light set to Flashing and then switch to Over drive once it became dark.  If the ride was long, I would have to switch from Over Drive to High once the low batter indicator started to flash.

Serfas True 500The LED for the Serfas TSL-500 is spec out for 50,000 hours of use, which basically means a lifetime of use.  I thought I read somewhere that the replaceable lithium ion battery was spec out at about 250-300 charges, which depending on how many night rides you do, could me about 1-4 years of use.  There is a low indicator on the light when 1/2 hour of charge is left on the battery.  Switching to a lower setting will of course extend this time.  A complete charge takes about 3-3.5 hours.  While charging, the charging indicator shows flashing blue and after a full charged, it changes to steady blue.

I would say this light is just about perfect for it’s output.  Currently it’s made in China, now if it were made in the US, it would get top ratings.  Since it uses a rechargeable battery, this does make the Serfas True 500 a greener product vs disposable battery units.

The Serfas TSL-500 retails for $150 and can be purchased direct from Serfas (

Incoming search terms:

  • serfas true 500
  • serfas true 500 review

About Author

Tom Crandall

Totally into multi-sports including triathlon, swimming, cycling, running skating and movement in general. Love to trail run and hang outdoors.

Leave A Reply

EndTheTrendNow Newsletter

Come Join In The Fun!

Close this popup

We are starting up a newsletter that we hope our readers...YOU...will look forward to month after month.

  • Fun News
  • Great Articles
  • Helpful Fitness Tips
  • Nutrition