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Effetto Mariposa Giustaforza II 2-16 Torque Wrench


Item # EFF000B

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Item # EFF000B

Your life depends on a quality bike build.

With the nearly constant refinement of bike parts and pieces, we've entered into an era of very lightweight components and frames. While this makes for easier rides up the mountains and more comfort out on the flats, the increasing importance of respecting manufacturer's torque specs makes an accurate torque wrench, like the Effetto Mariposa Giustaforza II, almost a necessity.

Effetto Mariposa is named after the butterfly effect, and in bike terms, suppose that you or a hamfisted mechanic makes a tiny error while torquing a fastener on your bike. And perhaps more likely than the butterfly flapping its wings in Brazil and creating a tornado in Texas, that one mis-torqued bolt could lead to a chain of failures and potential disaster on the bike. Independent tests at the Interbike trade show with passerby's and volunteers show beyond doubt that human hands are not torque wrenches. Effetto Mariposa Giustaforza II Torque Wrench DetailAnd no matter what any mechanic says about their ability to "feel" the right torque, they'll be wrong nine times out of ten.

The Effetto Mariposa Giustaforza II Torque Wrench is specifically designed for bicycle applications and will give readings between 2 - 16 Nm to +-4% accuracy. The Giustaforza II is the smallest and most compact adjustable torque wrench we've ever seen. It's roughly the size of two 20g CO₂ cartridges stacked end to end. The body is made of machined aluminum and has coarse knurling on the handle end to give you a good grip and delineate the correct place to grasp the wrench for use. The greatest aspect of the Giustaforza II is the tiny bit head. While it doesn't ratchet (and neither does your 5mm L-bend hex wrench), it will fit into the smallest of spots, like hard-to-reach seatpost clamp hardware. It's smaller than ever and rounded to fit into these odd spots on your bike. It has a powerful built-in magnet to hold your tool bits in place while you work. The torque settings are easy to read on a linear scale in a window machined into the handle, and adjustments require only turning the end-mounted dial to the proper torque spec.

Our Giustaforza II Torque Wrench kit also includes a 14-piece bit set that uses a standard ¼" fitting and has the following items:

  • Hex bits -- 2, 2.5, 3, and 6 in 25mm lengths and 4, 5 in 100mm length
  • Torx bits -- T10, T15, T20, and T30 in 25mm length and T25 in 100mm length
  • Phillips screwdriver bits -- #1
  • Common Screwdriver bits -- 3/16"
  • 100mm magnetized extension

Please note: Effetto Mariposa recommends storing the Giustaforza with the torque dial turned all the way down to zero to preserve the calibration of the tool.

Tech Specs

Other Tools:
[10x25mm] HEX2, HEX2.5, HEX3, HEX6, T10, T15, T20, T30, -3/16, +PH1, [3x100mm] HEX4, HEX5, T25, [1x100mm] extension
Claimed Weight:
180 g
Recommended Use:
bike maintenance
Manufacturer Warranty:
limited lifetime

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