Bike Test: Trek Slash 8

Trek Slash 8

There has never been a better time to purchase a new mountain bike. The new technologies are amazing and more affordable than ever. This allows you to get a bike that either enhances your skills or compensates for your weaknesses. The Trek Slash 8 is labeled an enduro bike, but it is really an all-around trail bike that can handle rougher terrain. It climbs well, gives you confidence on descents and is reasonably priced. We spent a number of days riding different disciplines in varying weather conditions; the Slash 8 got a true wrecking-crew shakedown.


This entire bike has plenty of acronyms to describe the engineering process of each component. We’ll leave it to you to do the research if that interests you. The aluminum-framed Slash 8 brings to mind that truck commercial advertising “military-grade aluminum.” That just sounds tough, and that is how this frame felt—super stiff and lighter than it looks.

The Knock Block is a unique way to avoid downtube destruction.

The seatstay linkage has a reversible chip called the Mino Link that slackens the head angle half a degree and changes the bottom bracket height by 3mm. This is probably not a trailside adjustment you’ll be making regularly, but it can be done in a little over a minute. We did use it in the steeper/taller setting on a long climb and reversed the link at the top for an extremely aggressive descent. It is similar to the old-school practice of lowering your seatpost for descents. All in all, we preferred the Slash 8 in the lower, slacker setting and adjusted our riding for the occasional pedal strike.

SRAM GX Eagle operated with zero complaints.


You can’t go wrong with SRAM’s Eagle GX at this price point. The entire bike is littered with quality parts from SRAM and Bontrager. The wheels don’t quite match the durability of the rest of the bike, though, so we found ourselves truing them a couple of times during our test. The SRAM Guide brakes got the job done, but we would prefer a little more stopping power and modulation. For the price of this bike, though, the components are a good value. All the contact points were dialed—from the comfortable saddle to the grips. The wide bars and short stem, with the 35mm diameter, really enhance the cockpit of this bike.

RockShox’s Deluxe RT3 offers no gimmicks, just function.


The shock/fork combo on this bike is an amazing value at this price point. Setting up the suspension properly is critical, though, so we made sure we got it dialed. First, we set sag to 35 percent in the back and started with the recommended rider weight setting on the fork, which put it at 22 percent. This is stock suspension with factory volume spacers. While riding, we increased the rebound settings faster, one click at a time, until we found our sweet spot, which improved the ride quality tremendously. The fork felt best at 14 out of 20 clicks from the slowest setting. In the rear, we went with eight out of 10 clicks from the slowest setting. These were unusually high settings, but the bike still felt stable and predictable. With the earlier slower settings, the bike felt sluggish, heavy and lazy in the turns. Once the rebounds were increased, the bike pulled up with less effort. Manuals were way easier. The bike was able to carry momentum through the turns better, and it just felt much more responsive. On extremely big hits and high-impact landings we might reconsider, but that was not the type of riding we were doing during this test.


There is still a debate over 27.5-inch- versus 29-inch-wheeled bikes in the enduro world. It comes down to handling versus speed and efficiency. We won’t go into that debate here, but we will say that a 6-foot-tall rider will appreciate this bike. Since we tested a 19.5-inch bike, we focused on taller riders’ needs. The Slash 8 rolls fast and smooth. The suspension and geometry work well together.

Climbing: Our trail ride began with a long climb (nearly an hour of rutty, rocky, sometimes sandy singletrack) followed by a fire-road climb that averaged an 11-percent grade. You gotta pay to play, so if you want the good descent, you’ll pay for it in sweat equity. The first noticeable issue we had was pedal strikes—not many, but enough to make us aware that the Slash 8 has a low bottom bracket. Now, we are not saying it’s too low; we just had to make some adjustments to our pedaling rhythm over obstacles and prepare for a few stutter cranks and back-pedaling situations. We were very pleased that this 19.5-inch frame size comes with a proper 175mm crankarm. So many other manufacturers are cheating low bottom brackets with short crankarm lengths these days. It was refreshing to have the pedal leverage, as well as an option to run shorter cranks in the future if desired. The stock XR4 tires hooked up well. They were malleable through the technical terrain and rolled fast on hardpack. Most of us climb to descend, and there wasn’t really anything negative to say about the journey.

Flow: The top of the hill can never come soon enough, and it was only 2 miles of ridgeline now to get to the descent. Quick up-and-down hills had us using the entire 12 gears and dropper post like a game of thumb war. The dropper post did its job, but it is finicky, wanting you centered on the saddle for it to release and drop. There was always a delay or hesitation, but we learned to adapt to this small idiosyncrasy. The post had a slower return rate than most other droppers we have tested, but that can be interpreted as good or bad depending on your personal preference.

The Slash 8 climbed well both in the saddle and standing, but the top tube felt a little shorter than we would like. It is funny that these days 5–10mm is noticeable between frame, bar and stem lengths. Again, this is a trade-off, because the little bit you resent on the climb, you will appreciate on the descent. Once headed downhill, the shorter top tube is actually preferred.

SRAM GX Eagle operated with zero complaints.

Finally, the real descent arrived: super-fast singletrack with every type of soil and terrain. The Slash 8 was home. Heading into the first set of hardpack switchbacks, the front end pushed away a little. Heading into the next turn, the same thing happened. These XR4 tires roll great, but they are not the ideal spec for this bike. The back tire wasn’t really an issue, but a Bontrager G4 would have been a better spec in the front. The geometry felt great, and the suspension was dialed. The only drawback was not having complete confidence in the front tire at high speeds. The good news is that this is an easy fix and not incredibly expensive. A front-tire upgrade would definitely offer more confidence.

The Slash 8 handled the roughest rock gardens with ease. The 29-inch wheels worked well, and the faster we went, the more our bike smoothed out the trail. The suspension pushed all the way through the stroke, front and back, a number of times, but we didn’t know it until we checked the indicators when we stopped. The front end is a little heavier than we expected, but after checking the specs, we realized the rear end is just a little longer than most of the bikes we’ve been testing lately. The negative is that pulling up to manual is a little harder; the positive is tons of stability on faster descents. Once again, it is a welcome trade-off. Jumping was extremely comfortable and predictable. The bike is well-balanced in the air and popped off every feature, once we had our suspension dialed.


We would upgrade the front tire to something much more aggressive. Longer (170–180mm) dropper posts are nice for taller riders. Adding additional volume spacers to the suspension would further improve the ride quality for heavier (175-plus-pound) riders.


The Slash 8 is a great entry-level enduro race bike. With the mixture of suspension and components, this bike really is a good value. For non-racers and resort riders, it offers the perfect mix of pedaling and descending capabilities. It can also be considered a big-travel trail bike, as it pedals remarkably well for having 150mm of travel. If you are a trail rider with no intention of cross-country racing, this is a great all-around offering. New price as of 5/26/2019-$3,479.99


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