I’ve been testing the WTB Scraper 27.5 mountain bike rims for several weeks now and they have quickly transformed my bike from a capable XC trail bike into an adventure rig worthy of the most challenging terrain. Is wider really better when it comes to mountain bike rims? Read on to find out.
Specs and Setup
WTB offers the Scraper rims in 27.5 and 29er diameters and both are designed for plus-size tires. What’s particularly exciting is that this 27.5+ rim will fit many 29er frames if you get the right tire. For example, the VEE Trax Fatty tires mounted to the Scraper rims won’t fit my Santa Cruz Tallboy frame (or Fox 32 29er fork for that matter) but the WTB Trailblazer 27.5 tires work just fine (check out this review of the Trailblazers.)
The Scraper rims are tubeless-ready, meaning all they need is a little tape and they’re good to go. Chris at Loose Nuts set my wheels up, and they’ve worked flawlessly so far. In fact, I was able to mount the Trailblazer tires to the Scraper rim with a floor pump and zero soapy water. The VEE Trax Fatty tires mounted using an air compressor, though I don’t know if that was necessary since we didn’t try a floor pump.
At 45mm, the Scraper rims aren’t the widest “plus-size” rims out there–Trek and Stan’s, for example, opted for 50 and 52mm plus-size rim widths, respectively. It would seem this is a compromise to make the Scraper 27.5 compatible with 29er conversion builds while also offering a decent width for 27.5+ adventure bikes like the Rocky Mountain Sherpa. As a 29er conversion rim, I’d like to try a slightly narrower rim to provide a bit more side-to-side tire clearance, since top-side real estate isn’t in such high demand on my 29er frame.
The WTB Scraper rims are made from aluminum and are compatible with standard J-bend spokes, which are generally available in shops around the world. The rims are 32-hole and weigh 650g. Competing 27.5+ wheels weigh around 700g, placing the Scrapers toward the low end of the weight spectrum.
Our build, utilizing Wheelsmith double butted spokes and Industry Nine Torch hubs, weighs in at 1080g (front) and 1200g (rear) not including tape, axles, or valves. This is by no means a lightweight wheel build (the spokes we chose aren’t the lightest out there) but then again, plus-size wheels are naturally going to be heavier than their standard counterparts.
On the Trail
On a particularly muddy ride I quickly understood how the Scraper got its name: chainstays on a 29er tend to scrape the mud off 27.5+ tires mounted to these rims (though thankfully the rims themselves aren’t being scraped). Honestly, there isn’t a lot of clearance on my Santa Cruz Tallboy with Scraper rims plus Trailblazer 2.8 tires, so I found these rims (plus tires) worked best in dry conditions.
That said, the Scraper rims are dialed! They’re stiff and responsive, and have stood up to minor rock and root bashes due to under-inflated tires.
I mentioned I was able to mount Trailblazer tires tubelessly with little effort, and I can also report the wheels have held their air well over several weeks of testing. My rear tire does seem to have a slow leak that needs to be pumped up once or twice a week, but I don’t know if the rim, our tape job, the tires, or the valve are to blame. Still, no burping on the trail to report thanks to the gorilla-like grip of the Scraper rim hooks. Seriously, these rim hooks are grippy–swapping tires out has been hard work!
The increased contact patch size afforded by the 45mm Scraper rims has proven to be a game changer for my rig. Rock gardens are smoother, holding lines is easier, and floating through loose conditions is a breeze.
I love the WTB Scraper 27.5 rims ($149.95 MSRP for 27.5, $154.95 for 29er.) Sure, they’re durable and feature excellent construction but not only that, they’re forward-looking while still bridging the gap between the past and present. Wide, plus-size wheels are the future of mountain biking and WTB is clearly leading the charge with thoughtfully-designed rims and tires.
Thanks to WTB for providing the Scraper rims for review.