Long travel, long range – the 2025 Trek Slash+ is here

Motor
TQ HPR50
Battery
580 Wh
Fork Travel
170 mm
Rear Travel
170 mm
Price
£7.500-11.000 (€7.999-11.999)
The new electric Trek Slash+ has 170 mm suspension travel, a 29er wheel up front and a 27.5 at the back. It’s designed as a mullet bike strictly, there is no room for a 29” rear wheel. The exception is the size small frame, it has 27.5” wheels at both ends. The Slash+ looks very much like the non-assist Trek Slash. It’s difficult to tell the two bikes apart, and that’s mostly thanks to the TQ HPR50 motor system.

The Trek Slash non-assist bike
Trek Slash+ emtb

TQ HPR50 and a 580 Wh battery​


Trek already know how to make a stealth ebike, they did so with the Fuel EX-e. The new Trek Slash+ gets the same compact and silent TQ motor. See my review of the motor for all the details.


But the Slash+ doesn’t get the same 360 Wh battery, this bike ships with a new 580 Wh battery. Using an adapter, the Slash+ is backwards compatible with the smaller battery. And they’re both detachable. The 580 Wh battery was introduced just a few weeks ago, and it’s an interesting one.

What’s so special about it, you say? It weighs 2,65 kg according to TQ. Just three quarters of a kilo more than the old, smaller battery. That’s about the same as an external mount 500 Wh Shimano battery used to weigh back in the days. I’m excited to see new battery tech making its way to ebikes!

The new and old TQ batteries


We haven’t tested the bike, nor the battery. But a bigger battery is also more powerful. The 580 Wh version won’t be pushed as hard as the smaller one when riding with high assistance. Consequently, less energy will be lost to heat. I won’t be surprised if, in some scenarios, the new battery has close to twice the range of the smaller one.

2025 Trek Slash+​

Trek starts off with the Slash+ 9.9 and the Slash+ 9.7, both with carbon frames. 9.7 usually means a half-way reasonable price tag. But the Slash+ seems to be about 10% more expensive than the Fuel EX-e, putting the Slash+ 9.7 at £7.500 (€7.999). The Trek Slash+ 9.9 easily beats that with its £11.000 (€11.999) price tag.

The Slash+ 9.7 is nicely specced, apart from the flimsy Bontrager XR5 tyres. The Shimano Deore M6120 brakes and Fox 38 Rhythm fork perform surprisingly well, although one might expect more for £7.500 RRP. Hopefully, Trek will find room for a decently specced and noticeably cheaper 9.5 version too. And I expect alloy versions will be out at some point.

Trek Slash+ specs
Trek Slash+ 9.7
Trek Slash+ 9.9


High pivot!​

It’s impossible to miss the rear triangle on the new Trek Slash+! This “high pivot” design looks so interesting and it’s not a new idea. We’ve seen high-pivot bikes before. Attaching the chainstays higher on the frame allows the back wheel to travel slightly rearwards as the suspension is compressed. That way, the wheel won’t hook up as hard when going into obstacles. The disadvantage was decreased pedaling efficiency.

One might argue pedaling efficiency is of less importance on an emtb. But this is a mild and lightweight emtb that needs to pedal well. Trek says the size and placement of the upper idler has allowed them to create a high-pivot bike that pedals well. And the anti-squat graph they provide sure looks promising. The non-assist Slash has got a similar design, so chances are we’ll have a comparable result on the + model.

The high-pivot design
Flat leverage ratio
Adjustable leverage ratio

Frame geometry​

I think the geometry of the Rail and Fuel EX-e has been great. And unsurprisingly, the Slash+ has slightly burlier looking geometry data. Trek has ditched their “Mino-link” adjustable frame geometry and replaced it with an adjustable headset cup. The headset can be set to “slack”, “nominal” and “steep”.

In the normal, I mean nominal setting, we get a nice and slack 63.5* head angle. The effective seat tube angle is about 77*, depending on frame size. According to this geometry table, the chainstay length is all over the place. Thankfully, Trek tells us it’s 434 mm for size S, 440 mm for M & L and 445 mm for the XL.

2025 Trek Slash+ geometry
2025 Trek Slash+

The longest wheelbase is achieved with the headset cup in the slack position, that gives us a nice 1.276 mm for size L. It’s not super long considering the long suspension travel, that’s because of the quite short chainstays. The Slash+ has the looks of a burly and capable descender that leans more towards playfulness rather than stability.

My thoughts​

Who wants a burly, long travel, hard hitter with a mild motor? Quite a few people, probably. I get the impression some people will buy a ~150 mm travel superlight emtb and attempt to increase suspension travel and slacken the bike. For all of you, this might just be the bike you really wanted! And if you insist on increasing the fork travel, Trek says 190 mm will be fine.

The TQ display sits integrated in the toptube.
Trek Slash+ 9.9 and the TQ HPR50 motor.

I think the high pivot design looks very interesting. It seems there was an issue with chain drop when it was introduced on the non-assist Slash, but this is supposedly sorted. And the light 580 Wh battery is very welcome on a lightweight ebike. It should offer good range in combination with the mild TQ motor.

But is the Slash+ really a Superlight bike? I can’t see Trek claim it’s superlight, and I can’t see them stating the weight anywhere. Running 38 mm stanchion forks, it probably isn’t superlight. But I’m sure it’s light enough for me. Somewhere not too far above 20 kg perhaps?

Update: Bike weight is now out on the Trek website. 20.38 kg for the 9.7 and 20.88 kg for the 9.9.

Riding the Slash+ 9.9
The 9.9 model has a Rockshox Vivid shock handling the 170 mm rear travel.
The TQ HPR50 motor
About author
knut7
Main editor at emtbforums.com and owner of emtb.no.
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Comments

Second ride.
No crash no nothing.
Both sides. Broken right through. Warranty accepted. Will have a new seat stay in 2 weeks. Hope it doesn’t happen again

That's crazy for a new Trek, such a well-established well-built bike brand.

Hope it was a one off.
 
I’m pretty sure it was a one off. Lovely bike to ride and I come from a full power Rail and an Evil offering v2. Can’t wait to get back on this horse. Such fun !
 
All bikes have issues. It’s how the manufacturer looks after the purchaser that matters. In this case it has been phenomenal. I have broken a lot more alloy bikes than carbon. I cannot wait to get back on this bike.
 
All bikes have issues. It’s how the manufacturer looks after the purchaser that matters. In this case it has been phenomenal. I have broken a lot more alloy bikes than carbon. I cannot wait to get back on this bike.
If it’s a design flaw then it will be happening again….. sorta like all the evil bikes cracking at the water bottle mounts or Kenevos snapping alloy shaft coil shocks. Buying a bike the first year they are out means you are the beta tester.
 
If mine arrives before Friday I will be taking it to a bike park and I can assure you that I'll test it as hard as I'm capable of doing and will let you know if I break the rear triangle (doubtful, likely not a piece of junk ;) ). Scheduled date is 8/29 or 8/30 so not sure yet whether it will be available.
 
I received mine on Thursday and took it up to Sunrise in Greer, AZ on Friday. I also took my Firebird (non-EMTB) and did 4 runs with the Slash+ and 5 with the Firebird. I was faster on every single run with the Firebird and by a significant margin but I've had that bike for almost 3 years and raced multiple enduro events with it and had it at Sunrise more than a few times so it had a significant advantage going in. It is also way lighter and, honestly, pedal assist at a lift assisted bike park is not particularly useful. I'm not anywhere near a pro or high level amateur but I'm in the top 20% on Strava times on every trail I've ridden up there so I'm not incompetent either (just to give you a skill baseline).

Likes:
Very smooth in eating up bumps, absolutely does what it is supposed to do
TQ motor (still by far my favorite) feels very natural
Overall quality of components is also excellent although I'm not sure I love the handlebars that came stock with the 9.9. I'll likely change them out. Everything else though, top notch

Dislikes:
For that scenario it is just too heavy at 49lbs with pedals. The reason I was faster with my Firebird is simple, I was able to execute switchbacks and hard corners much more easily. May try it with the smaller battery next time.
Aforementioned handlebars
Too hard to get up in the air/not poppy enough but I think I should expect that.

For fun Enduro riding where e-mtbs are allowed I think this is a great bike but I can't see it as a park bike. I can see it as a great training bike for working on enduro type skills or an e-MTB enduro race. Better in every single way than any full power e-MTB I've ridden (I really just don't enjoy them at all).

I'd go 4.5/5 stars for a rating. Behind my Mondraker Neat RR SL which is still best e-MTB I've ridden but serves a different purpose.
 

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Rode a 30 mile ride with it yesterday on more familiar terrain. Again, I'm going to state up front that I put it in a disadvantage intentionally as I want to find out where I will find this bike most useful. My main focus was on a very non-technical blue trail with around 570' of elevation gain/762' of descent over 6.2 miles, i.e., very easy. Actually, I just looked it up and it has been changed to green which I agree with but it was blue forever, mostly because there is a roughly .75 mile section with some exposure but, eh, it is smooth there.

Anyway, I have done this trail, many times and had numbers to compare it with my Mach 4 SL and my Switchblade. Running it in medium assistance (no need for full because I was never in a place where it would have mattered), it was the slowest of the bikes by a wide margin although I did have to interpret the numbers to figure that out as I was riding with some people I needed to wait on a bit. Therefore it is possible I'm a bit off but as far as I can tell it was around 5:20 slower than my fastest time on my M4SL and around 2:58 slower than my fastest time on my Switchblade. You may think I would be disappointed in this but it is the exact opposite. I really want to use this bike to get better. I can just throw the M4SL around and the Switchblade isn't much different which makes those tight descending corners very easy but it means I'm likely "cheating" and using straight power instead of better technique. If I can best those times on this bike I will have actually gotten better.

In the end, until I get a lot older than 52 or have some sort of injury I'm never going to be using a e-mtb as my primary bike. I simply enjoy the challenge of climbing too much but I do see them as potentially awesome training devices and I think both the Mondraker Neat RR SL and this one fit the bill. I have finally cured myself of wasting money on full power e-mtbs that I immediately become bored with and found two that actually enhance my riding.

NB: I don't tell other people how to enjoy MTBing and fully support any one that wants to ride a full power e-mtb or otherwise. I can only say what is fun for me and have literally zero interest in telling others how they should enjoy life, hobbies or whatever so don't take my words as anti-full power.
 
and, honestly, pedal assist at a lift assisted bike park is not particularly useful.

I'd go 4.5/5 stars for a rating. Behind my Mondraker Neat RR SL which is still best e-MTB I've ridden but serves a different purpose.

It's great you have your bases covered with multiple bikes.
For bike parks, I appreciate the ability to remove/swap the battery from the TQ Treks. I did that at sun peaks and it helped, but at 4lbs for the 360wh was not a huge difference. I see the 580wh battery is 5.9lbs. That's where I see the Slash+, remove the battery and you've got a <40lb park bike.

I just returned from 4 days of camping at a local spot that has multiple DH trails dumping into the campground, ranging from 1900' to 3500'. The EXe with the enduro build is just about perfect there. I can get one 3500' lap or two 1900' laps out of the 360wh battery, or swap batteries at the bottom for extra laps. I also enjoy climbing, but the EXe saves me so much time I can get more laps in and still have afternoons free for other adventures!
 
I’m still waiting on a seat stay. Hopefully early next week. Haven’t heard from the factory regarding what happened to mine yet. Pretty sure it was a one off. Have purchased a transfer neo 200mm dropper and it can slam to the collar on my large. Whoop
 
I received mine on Thursday and took it up to Sunrise in Greer, AZ on Friday. I also took my Firebird (non-EMTB) and did 4 runs with the Slash+ and 5 with the Firebird. I was faster on every single run with the Firebird and by a significant margin but I've had that bike for almost 3 years and raced multiple enduro events with it and had it at Sunrise more than a few times so it had a significant advantage going in. It is also way lighter and, honestly, pedal assist at a lift assisted bike park is not particularly useful. I'm not anywhere near a pro or high level amateur but I'm in the top 20% on Strava times on every trail I've ridden up there so I'm not incompetent either (just to give you a skill baseline).

Likes:
Very smooth in eating up bumps, absolutely does what it is supposed to do
TQ motor (still by far my favorite) feels very natural
Overall quality of components is also excellent although I'm not sure I love the handlebars that came stock with the 9.9. I'll likely change them out. Everything else though, top notch

Dislikes:
For that scenario it is just too heavy at 49lbs with pedals. The reason I was faster with my Firebird is simple, I was able to execute switchbacks and hard corners much more easily. May try it with the smaller battery next time.
Aforementioned handlebars
Too hard to get up in the air/not poppy enough but I think I should expect that.

For fun Enduro riding where e-mtbs are allowed I think this is a great bike but I can't see it as a park bike. I can see it as a great training bike for working on enduro type skills or an e-MTB enduro race. Better in every single way than any full power e-MTB I've ridden (I really just don't enjoy them at all).

I'd go 4.5/5 stars for a rating. Behind my Mondraker Neat RR SL which is still best e-MTB I've ridden but serves a different purpose.
Thanks for the review. Is this a medium?
 
Thanks for the review. Is this a medium?
Yep. It is a medium and I've now had the opportunity to dial in the suspension quite a bit and I've already seen a lot of improvement on my ability to ride it fast in corners. I still need to hook up my BYB system up and dial it in further but I can say this for sure, don't trust the recommended settings on the shock. I put my Shockwiz units (my quick way to assess suspension) on the fork and shock and set them to playful. The fork was decently close and I didn't have to adjust many things but here's what I saw on the shock after the downhill and 30 mile ride I listed above (see Standard Settings pic). I then took did 4 runs on my the ~1 mile loop where I normally do my suspension tuning. It has everything I need other than longish rock gardens but that's ok. 4 rides and adjustments later I saw all green (shown in the Shock after fixing... pic). For the Fork, it wasn't too far off but here's what I saw after the original ~45 miles (see Fork pic attached). I forgot to take a screenshot after adjusting but it was all green after making the recommended corrections. I did a quick 18 mile ride last night after work and the difference was noticeable. I moved into the top 10 on multiple Strava e-mtb segments with it in these settings so I think they are pretty close to dead on. I'll still hook up the BYB when I have a chance to do more testing. Probably won't ride it again for a while though. Prepping for a race in the fall that is more on the XC side so it is no help to me.

Bike is as quiet as any TQ (I cannot stand riding loud, whiny motors) even with the high pivot but I did wax my chain before I ever rode it.
 

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