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

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  • Boxcar Stem

    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

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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Ever since we introduced our Quick Release Seatcol Ever since we introduced our Quick Release Seatcollar years ago, folks have been requesting a bolt-on version. But with so many other seatcollars on the market, we didn’t initially take the requests too seriously. Since the advent of dropper-posts, we started thinking about this more often. There really is a need these days for a seatcollar with deeper, more uniform clamping distribution: Enough to keep your dropper post from slipping in the frame, but also with a large, evenly dispersed clamping force to avoid the dreaded “dropper-binding”.

  The convex back of our “floating button” design evenly disperses clamping force, and avoids pinching or binding at a lighter weight than a steel barrel, is replaceable if damaged, and follows the simple PAUL aesthetic nicely.

  These are lovingly machined by us to the highest tolerances out of USA sourced 6061 & 7075  aluminum right here in sunny Chico, California. They are currently available in 30.0mm, 31.8mm, 33.1 and 35.0mm, in polished, purple, black, silver, and with orange accents.

Available NOW on our website, or from your favorite local bike shop. If you want to learn more about it, search up our latest YouTube video. 

Have a great weekend, we hope you get to RIDE! ✌️
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I know, it’s not that big of a deal, but it does c I know, it’s not that big of a deal, but it does come in handy and look real elegant. Our Klamper-inspired topcaps now come in a version with a built-in 5mm spacer. Some carbon fork manufacturers specify it, and sometimes you just wanna keep a touch of extra steerer tube around for adjustments or resale value. Anyways, The Rook is now live on the website! ♟️
We’re SUPER excited about this new trail network o We’re SUPER excited about this new trail network opening just up the mountain from us above Butte Meadows! Two trails are already finished, with 5 or 6 more in the works, and an eventual plan to connect this to the @sierratrails Connected Communities trails. Yeah, this is big! 
  So… we asked @the.scorps if he’d be willing to donate artwork for a fundraiser T-Shirt, and he doodled up this fun drawing of the Colby Mountain Lookout. These are VERY limited edition, so if you want a sweet rare McNally shirt while raising money for a killer trail system in Lassen National Forest, head to our website quick before they’re gone!
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Paul Component Engineering
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  • 530–345–4371
  • 11204 Midway
  • Chico, CA 95928
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