Everything’s better with lasers, right? From the company that brought you the laser stem alignment tool, we present – the Linientreu laser derailleur tool. Most mechanics are probably asking why you would need such a tool, but Tune says that the device makes it easier to set up your shifting, whether you’re a complete novice or a seasoned pro…

Fine Tune your rear derailleur with new Linientreu precision laser toolFine Tune your rear derailleur with new Linientreu precision laser tool

Fine Tune your rear derailleur with new Linientreu precision laser tool
All photos c. Tune

Fitted with a 5mm Allen or T25 Torx bit, the Linientreu is designed to plug into the fixing bolt of your rear derailleur. Then the adjustable laser can be moved so that the beam is cast directly on the upper pulley wheel of the rear derailleur.

Fine Tune your rear derailleur with new Linientreu precision laser toolFine Tune your rear derailleur with new Linientreu precision laser tool

Theoretically that should allow you to perfectly align the derailleur with each gear for perfect indexing, and Tune even claims it allows for precise limit adjustments as well. It seems like the device would also indicate whether the hanger is straight (at least in certain directions) since the laser would have a diagonal slant – though without using it, it’s hard to tell how accurate it would be.

Tune says the tool is compatible with 7, 8, 9, 10, 11, and 12 speed drivetrains and is patent pending. No price is given, but since it’s Tune – the tool weighs 200g.



  1. This is cool, and make sense, but all derailleurs can be micro adjusted after it comes off off the stand. Sometimes it can be micro adjusted on the fly mid ride. I can only see this tool be absolutely necessary when you are mass producing bikes and replace actual test riding with this laser alignment tool to improve manufacturing efficiency while minimizing unit to unit variation. If the bike will have to be test ridden anyway before handing it to the customer, then why does it matter if it lines up absolutely perfectly the very first try.

    Still though, I would want one, simply because I like cool tools.

  2. i love these tools! that means another non-cyclist will be selling his/her cycle on craigslist for dirt cheap, all upgraded just for me…..

    • Not sure you know what conspicuous consumption means because,

      A. We don’t know the price so it may not be expensive
      B. Even if it is expensive, who goes around flaunting their tools?

      • If you think for a moment that whoever buys this – regardless of price – won’t be whipping it out or at least mentioning it all the f-ing time then you are wrong.

  3. Laser accuracy, with a tiny, flexy bodyfor actually correcting anything. If you want accuracy and a usable tool, get an EVT or Abbey.

  4. Could be critical for the coming 17-speed drive trains…

    Agree with Rusty — would be cool to see it integrated with an adjustment tool.

  5. Still doesn’t fix the fact that your hub is insanely loose and your cable and housing are blown and that’s why your bike doesn’t shift.

  6. IF you actually REQUIRE this tool to adjust your rear mech accurately you will be incapable of using it … One of the most ridiculous and superfluous bike-tools I have ever seen!

    A drivertrain gives multi sensory feedback if incorrectly adjusted:

    You can hear it.
    You can see it.
    You can feel it.

    Even the infamous Campagnolo corkscrew is more down to earth and more useful in a bike-shop toolbox, than this contraption.

  7. Misguided concept. It will only work for its intended purpose if the hanger is perfectly straight – and this tool can’t help with hanger alignment. And that would be a better purpose.

    It would need to mount to the plane of the wheel to function for its stated use.

  8. I disagree with all the eyeball / listen comments – an 11s chain is 5.5mm wide and to account for that degree of tolerance in two planes I find most people are kidding themselves without a tool. I’ve often seen really good mechanics claim a straight hanger using tools like the campy hanger tool (relies on a good eye) only to find themselves a long, long way off when checked with an EVT.

    This tool looks like a novelty but that doesn’t mean good tools aren’t valuable for hanger alignment.

  9. Want perfect….perfect…..perfect RD setup.

    Step 1: Check frame alignment-on a table.
    Step 2: Make sure that rear wheel is perfectly true.
    Step 3: Check derailleur hanger alignment against that perfect wheel.
    Step 5: Set high limit screw with cable detached.
    Step 6: Attach that cable and turn the barrel adjuster out past correct. Shift to the low cog and set the low limiter screw.
    Step 7: If the b tension screw is off, turn it in or out as needed and run the chain up and down the cogs 2-3 times. readjust as needed.
    Step 8: Fine tune cable tension.
    Step 9: Ride the bike around the block….just to make sure that under load everything is still just right.

    What’s the problem with this silly laser tool? It doesn’t check frame alignment, or that the bb is faced in line with the dropouts, or that the hanger is straight. It also only works on bikes in the stand, with no torque flexing the bike and its drivetrain parts oh so slightly (let alone the effect that suspension compression has on the drivetrain).

    I don’t bother putting frames on an alignment table and only check hanger position if the derailleur looks off……and I get perfect rear shifting on the bikes I assemble or service. If you can straighten a sub-2mm disc brake rotor by sighting it through the pads on a bike, you can see if a 5.5 mm wide chain isn’t aligned right. It’s well within the bounds of human perception.

    This is a flawed tool which provides one very precise metric for getting good shifting, but on a straight frame that’s an easy job. On a frame that has an alignment issue somewhere, this thing is useless. On a full suspension bike that’s adjusted in the stand without factoring in sag or travel, this thing is useless.

    Having worked at bike shops for a few decades, I’ve found that some customers like the idea of wrenching on their own bikes more than the reality of doing so. They think that with the right tools, they can rival the work that guy with the greasy apron and a few thousand hours of wrenching time does. And they buy exotic stuff, from (so, so choice) Var and Campy toolsets of yore to spoke tension measuring tools to titanium hammers (the worst use of titanium…..EVER!!!!). This tool will appeal to these people, and then it will sit, unused and dusty on an unused, dusty workbench. And when the tool wanker who bought this silly tool tries to sell it to his local mechanic (who will GLADLY pay for a Var or Campy tool kit, which is useful) it won’t sell. And then it will either go back to bike tool purgatory on the bench (or maybe in the toolbox) of unused stuff…..or get thrown away.

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