Review: White Brothers Loop TCR Fork

By Josh Patterson, photo by Justin Steiner

For years White Brothers forks were instantly recognizable by their press-fit aluminum lowers. Long after other companies had transitioned to using cast magnesium, White Brothers stayed the course. Why? Well, White Brothers is a small company, and casting magnesium is very expensive. Using aluminum allowed White Brothers to quickly develop suspension forks to meet the needs of new wheel sizes, i.e. 29ers and 650b, years before it was a viable business venture for larger companies like Fox, RockShox, Manitou and Marzocchi. The downside? The press-fit lowers were prone to misalignment, resulting in increased stiction. When White Brothers unveiled the LOOP suspension fork line last year at Interbike it was clear they were ready to go head-to-head against the big names in mountain bike suspension. Let the battle begin.

The Tech

The TCR in the LOOP name stands for Threshold, Compression, and Rebound. The LOOP TCR features an eight-position compression-damping knob. The three positions providing the most compression damping rely on magnets to create a firm pedaling platform—this is the threshold zone. The threshold settings can be fine tuned by inserting a 2.5mm Allen key into the middle of the compression knob.

The magnetic threshold differs in design and function from the inertia valve technology developed by Fox—which uses a brass cylinder to regulate the flow of oil through the compression circuit—yet the goal is the same: to create a fork that minimizes rider input (bob) while remaining sensitive to trail input. According to MRP’s Paul Aieta, magnets are well-suited to providing a firm pedaling platform. “If you’ve ever played with a magnet, you know that once you pull it a certain distance away from a piece of steel there is no ‘return spring.’ With our magnetic valve you get a locked-out feeling, but when you hit a bump the valve opens quickly and stays open until the rebound stroke closes it,” explains Aieta.

On The Trail

I found the LOOP’s threshold adjustments to work as advertised. It’s not a lockout, but a platform firm enough for out-of-the-saddle pedaling. There are downsides. The magnetic damper requires an initial impact to activate the suspension. It is also noisy. When trail impacts, rocks, roots, etc., exceed the fork’s threshold, the initial suspension action is harsh and, in the firmest position, there is a noticeable shudder as the fork moves through its travel. The noise and shuddering are both the result oil of attempting to move through a small bypass valve. I didn’t spend much time riding in the three threshold damping positions, as they were significantly firmer than my test bike’s (Yeti 575) rear suspension. This 150mm-travel fork was better suited to riding in the remaining five positions of compression damping outside of the magnetic threshold zone.

I felt the fork rode best two clicks out of the threshold zone. Once outside the threshold zone the fork moved through its travel smoothly, with no shuddering and less noise. Rebound damping is controlled by the red knob on the bottom of the right fork leg. The 14-position damper provides a wide range of adjustments; eight clicks from fully open is where I found my sweet spot. I settled on approximately 72psi for my body weight (150lbs. w/hydration pack).

The Loop has a linear feel and makes use of all of its travel without feeling divey. In fact, the LOOP rides significantly higher in its travel than comparable forks I’ve ridden. According to Aieta, this is by design. I appreciated this feeling through banked turns and high speed g-outs. Stiffness was excellent. All LOOP forks are 15mmQR and use White Brothers’ proprietary thru-axle. I can’t say for certain if it was the thru-axle, the suspension’s performance, or both, but the LOOP holds a line like a champ.

Final Thoughts

Overall, I found the LOOP to be a good trail fork with some eccentricities. The fork’s action is smooth, but noisier than others. The magnetic threshold is better suited to 80-100mm travel forks in an XC-race application than it is for long-travel trail bikes. Small bump sensitivity could be better, though medium and large hits were handled well.

Specs

Price: $795
Travel: 150mm, internally adjustable to 140mm and 130mm
Weight: 4.16lbs. w/ thru-axle
Steerer: aluminum, 1 1/8” – 1 1/2”
Spring: air
External adjustments: threshold, compression, rebound
Disc mount: 74mm Post mount
Country of origin: lowers and crown made in Taiwan, internals made in Grand Junction, Colorado.
Online: mountainracingproducts.com/white-brothers