Trek Slash+ 9.9 mountain bike update

Last year when I started using the new Slash platform, Trek was already working on the e version of the Slash, and as a result we have what I ride here which is now called the Slash+. The Slash+ is a 170mm all-mountain, lightweight mid-strength offering. It features a small drive unit and a medium-sized battery in an attempt to maintain handling like the analogue version of the Slash, yet with enough assistance from the motor to make a real difference to your ride.

The geometry, kinematics, and many details of the frame are all almost identical to the Slash, save for a few details like the top tube screen and switch to the left side of the bars. In fact, at first glance the screen is incognito: most people didn't realize that this was actually a new bike I was on, let alone that it had an engine. Trek keeps this simple with just two build levels to choose from, and one paint option for each.

The Slash+ list starts at $11,499.99 for the 9.7 and tops out at $17,999.00 for the 9.9 I have for testing. Although cheaper, both offer well-thought-out components and spec. To be honest, I actually expected the 9.9 I rode to be more expensive, given all the technology and electronics you get with it. This does not mean that it is perfect, which is what you aim to achieve in $ 1 in 18k: for me, in the repetition of my experience ​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​ I've been lucky of late that the trails haven't been as dry as they could have been as the Bontrager tires are very heavy in these conditions, and offer close to no grip. Fortunately, this is a useful little part, and it's not a deal breaker when buying a new bike.

So let's dive deeper into the new Slash+

First impressions

As I mentioned earlier Slash+ is similar to non-mortality Slash, with a few key differences. The most obvious (outside of the car) is the lack of storage on the frame, as you would expect something Trek couldn't do as it would affect the space taken up by the 580Wh battery. The charging port is at the top of the battery on the down tube, out of the way from the cranks and unlike other bikes, this is covered with a nice rubber gasket to keep out the weather and dust and mud.

The Slash's new top pivot design continues as you'd expect, with 19 top teeth keeping things spinning smoothly. The lower chain guide has also been revised, with direct mounting on the engine removing any possible inaccuracies in the system. The alignment of this was the cause of the chains breaking on the analog Slash, an easy fix for what was a major problem.. Full disclosure I have never experienced a single dropped chain on Slash or Slash+.

The TQ-HPR50 engine used in both the Fuel EX E and the new Slash+ has a very small profile that can easily be missed by the untrained eye. In most trail conditions, you can't hear the engine at all, the usual chain noise of the high pivot system, and the tires in the dirt. It has a torque of 50Nm, and the standard battery is 580Wh.

You can switch to the smaller 360Wh if you feel the need to lose weight and don't tend to use all the juice of the 580Wh. To do this, all you need to do is remove the two hex bolts to fix it in place, open the bottom cover, and take it out. There are two different end caps for different bearing sizes, so those are included in the exchange. If you're looking for more juice, there's a 160Wh bottle cage range advisor available.

Trek makes big claims about the new Slash+'s trickiness in terms of 'tonality' (how loud it is) aka understanding the sound the user hears with TQ motor vs analogue, full power and low power assisted bikes. E-bikes are so amazing that they are now introducing more, lighter and more natural in their power delivery. Cost is probably the only reason not to recommend one to someone looking for a bike with long legs.

Geometry

Like the Slash I rode last year, the Slash+'s geometry is aggressive, its mullet setup striking a fine balance between stability at speed and sharpness in technical terrain. Reach numbers are also generally the same with the same kick at 430mm and regular travel up to 519mm, with a big jump at the lower end of the range. This jump may be from the M/L size not being available now which is what I was riding before and now forcing me into a large. At first, I thought this would be a problem but honestly the access was there, the only problem being the lack of seat height that I would have had in the M/L.

The bottom bracket drop is low across the board and I never felt the need to lower it, the chainstay length is the same on the S, M, and L bikes (434mm), while the XL is now 5mm longer (439mm). The number sounds short and might make you question the 27.5″ rear tire (Trek didn't mention the use of a 29er rear tire like on the analogue Slash) but because of the axle path, the chain stays up to 19mm and will already start to stretch to about 11mm where the sag is 30%.

The head tube angle is adjustable ±1° using the compression headset cups available for purchase form Trek, and sits at 63.4° in the stock position. The seat tube angle stays close to 77° on all sizes, decently steep for a Trek but not when you're looking at something like the Forbidden.

On the road

The Slash+ is one of the only bikes I've ridden that is true to its claim of near-silent motor performance. It's a small detail but it's one of the first things you notice when you hop on or ride an e-bike.
For me, the bike performs incredibly well on fast, challenging terrain. Much like the Slash I liked so much, the suspension has a great balance of feed and grip, making it feel confident in both high speed and janky sections alike. After a short adjustment period, the rear end feels natural – if at all – and the bike cruises though jumps and off rock edges with ease. The platform provides a supportive ride on flowing roads as well, and slightly hides its long travel legs. This shouldn't come as a surprise since both the Slash (that's now Trek's Enduro Race bike) and the Slash+ use the same basic geometry and suspension platforms.

Because of this, it makes me wonder why Trek is updating their Rail with a powerful engine like the Bosch Performance Line CX Race or SRAM Powertrain when they have already proven they can make The Slash+ ride like a Slash. Would a few extra kilos really affect the build and ride so much that they need another bike? Although you notice less power than a full-power e-bike when climbing, it is not so important that your mates on a regular bike don't want you around, and you can likewise be accompanied by a large e-drive unit. -bikes if you're committed to making more effort than usual: it's not that big of a deal.

The only problem we encountered was a creak under pedaling that I couldn't figure out. I did everything but remove the engine and battery, apply new grease, clean and check the torque settings of the pivot, cranks and seat post, hoping I won't have to remove the engine. The sound is no longer a descent but something that turns heads when you step on someone on the open road.

Final thoughts

My time on the Slash+ has been great, one of the best – if not the best – e-bikes I've ridden…but I say this with a caveat. I like this bike but because of its small engine and low torque I would not choose it as an E-Enduro race bike. Enduro is still young in Australia and if you're fit, I think it'll be fine, but if you're going head-to-head with your doppelganger in something like Gasgas MXC then you've got your work cut out for you.

Trek's New Slash+ is a bike that's fun and flows with speed when pointed at the trail! If you watch the Trek out marketing video, they also think this is a bike designed to maximize the fun you can have with minimal effort.

Chapeau Trek for more fun times.