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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 – $172.00Price range: $156.00 through $172.00

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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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You’re damn right we’ll be at @made.bike, this You’re damn right we’ll be at @made.bike, this show is our PEOPLE! Come say hi and ask for some free limited edition @peace.sports colab stickers, check out Paul’s new @crustbikes , drop off some of those good Portland vegan donuts 🙃, and oh yeah, look at a bunch of shiny bike parts we machine in Chico California ✨👀✨. If you haven’t bought tickets yet, sneak in this discount code: YOUMadeIt for 25% off a day or weekend pass. This is going to be FUN, see ya there! 📸: @jadeelhardt
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We located the original old school factory that’ We located the original old school factory that’s been making bandannas in Greenville South Carolina from dyed-thru (double-sided), sewn-edge, 100% cotton since 1946! These are the REAL DEAL durable bandannas loved by greasers, hippies, and dirtbags all through the 50’s, 60’s, and 70’s, and they get real nice and soft after going through the wash a few times. Artwork is California Poppies, PAUL Parts, and Poison Oak, drawn by our good buddy @the.scorps. In stock now!
✨Downieville GOLD!✨ Those of you racing the Al ✨Downieville GOLD!✨ Those of you racing the All-Mountain category of the @downievilleclassic this year will receive a commemorative stem topcap by @paulcomponent ! 🏅
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Introducing the BËP. It’s just a handlebar plug Introducing the BËP. It’s just a handlebar plug, right? Sure, but when the machinist bike nerds at PAUL start 
designing, prototyping, (obsessing), and testing a project, even a simple bar plug can end up at 
NASA-level standards of tolerance, function, and reliability. 
We think we’ve arrived at the highest quality handlebar plugs in the world. Cheap rubber and 
plastic construction were never good enough. 100% CNC machined aluminum expanding-
wedge construction means that once tightened properly, they’re NEVER falling out or coming 
loose.
 Available in every color of the rainbow on our website, or from your favorite bike shop, now!
Paul Component Engineering
  • info@paulcomp.com
  • 530–345–4371
  • 11204 Midway
  • Chico, CA 95928
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