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Shop | Components | Boxcar Stems | 7/8″ Boxcar Stem

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7/8″ Boxcar Stem

There’s something about 7/8″ (aka 22.2mm) handlebars that seem to attract the most abusive riders out there, so we’ve taken our popular Boxcar stem and beefed it up even further. We already use 2024 alloy for all of our boxcar stems, as it has a higher fatigue and yield strength than 6061. We made sure the clamp was extra thick on this version and even added 2 more high-strength stainless faceplate screws. Is it overkill? Definitely. You’d have to run this thing over in a tank to damage it, but we’re pretty sure this will be the last 7/8″ stem you’ll ever have to buy.

Machined by us here in sunny Chico, California.

$156.00 – $172.00

Clear

Technical Information

  • Weight
    35mm: 180g (Including hardware)
    50mm: 201g (Including hardware)
    70mm: 220g (Including hardware)
  • Material
    American 2024 Aerospace Aluminum
  • Finish
    Anodized or Polished
  • Anodized Color
    Black, Silver, Pewter, & Purple
  • Bar Clamp Diameter
    7/8" (22.2mm)
  • Length
    35mm or 50mm
  • Stem Angle (deg)
    +/- 0
  • S.H.I.S. Steerer Clamp Diameter
    28.6 mm
  • Stack Height
    36 mm
  • Instructions
    Download
  • Torque Settings
    Steerer Tube: 5nm
    Faceplate: 4nm
  • Rise & Reach
    Download
  • Faceplate Width
    46mm

Product Story

The Boxcar stem was designed from the ground up to be stiff, strong and light. We went through several design iterations and believe we’ve reached the best combination of these three principles. Extensive real world and machine testing have proven this to be one strong stem.

With respect to torsion, the rounded box shape is some 25% stiffer than the competition. As for strength, we ran it through 1,000,000 cycles of above normal use stress without a single problem. How’d we get it so light, while still being so strong? We started with obsessive computer design time, then took the highest quality American 2024 aerospace alloy, and precision machined it to .002” tolerance (that’s really tight for a stem). We use over 20 different end mills, drills, saws and taps to make 1 stem.

This 7/8″ version comes in a zero rise in 35mm or 50mm length. All screws are the same pan head T25 Torx type screws in stainless steel. Why Torx? To encourage torque wrench usage and avoid strippage (People tend to overtighten faceplate bolts). Also the Torx head is wider, distributing stress better, and are the same wrench size as the ubiquitous rotor screws all makers use. Also SRAM has made a switch to T25 screw heads in almost all their products, which is a good sign.

As usual, by letting the function and material properties dictate the shape of the product, we have come up with another one of our often complimented and purposeful designs. Yes, it looks a little different, but with us there is always one good reason for this: to make it work as awesome as possible.

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Paul Component Engineering
  • info@paulcomp.com
  • 530–345–4371
  • 11204 Midway
  • Chico, CA 95928
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