Losi Lasernut U4 1/10 4WD Brushless RTR Rock Racer (Blue) w/2.4GHz Radio & Smart ESC

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Losi Lasernut U4 1/10 4WD Brushless RTR Rock Racer (Blue)
Price: $539.99
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The Losi Lasernut U4 1/10 4WD Brushless RTR Rock Racer is a scale replica of the renown Lasernut Unlimited U4 FIS (Full Independent Suspension) rock race buggy. Starting with the Losi TEN platform as a base, the Lasernut model adds items rock racers demand such as aluminum shocks, sway bars and adjustable turnbuckles. Working together with BFGoodrich Tires, the Lasernut U4 has scaled down KM3 tires that have an aggressive tread pattern that is capable of tackling a wide variety of terrain - from dirt and sand to chunky rocks and slick slabs.

The Lasernut is currently the only complete Unlimited U4 FIS racer on the market featuring all the technological advances drivers demand including the Spektrum Smart 130A Brushless ESC and Spektrum 4-Pole 1900kv 550 motor providing greater efficiency improving run times with increased power. Of course, the ESC is waterproof, completely programmable and comes pre-wired with a high-current IC5 connector. Drivers stay in control with a DX3 transmitter, a Spektrum AVC receiver with steering priority, and an officially-licensed Lasernut race-inspired scale U4RC body/roll cage with two different graphics and color variations. The Losi Lasernut Rock Racer is the ultimate U4 racer with scale looks, insane speeds and performance.

 



Features:

  • TEN 4WD Platform
  • Spektrum™ 130A Brushless SMART ESC and 4-Pole 1900kv 550 Motor
  • Spektrum DX3™ 2.4GHz radio system with AVC® and optional telemetry
  • Waterproof Components
  • 12mm race inspired threaded aluminum bodied shock absorbers and shock caps
  • Officially-licensed Lasernut Racing Scale Body & Cage
  • Officially-licensed BFGoodrich® Mud-Terrain T/A® KM3 Tires
  • Officially-licensed Raceline 2.2 Wheels
  • Sway bars
  • Three Oil Filled Gear Differentials
Specifications:
Approximate Assembly Time: No assembly required
Ball Bearings: Full set
Battery: Sold Separately
Body: Trimmed and painted
Brakes: Integral with ESC
Bushing Material: Metal
Charger: Sold Separately
Chassis: 0.12" (3mm) thick 6061 T-6 aluminum
Completion Level: Ready-To-Run
Differential: Sealed viscous filled
Drivetrain: 4WD
Drive Type: Forward/Brake/Reverse
Final Drive Ratio: 12.97:1
Front Track: 13.25" (336mm)
Power Type: Electric
Gear Pitch: MOD1
Ground Clearance: 1.75" (44mm)
Internal Gear Ratio: 3.89:1
Max Battery Dimensions: 5.45 x 1.83 x 1.38" (138.5 x 46.5 x 35mm)
Motor Type: Brushless
Pinion: 12T
Product Height: 8" (203 mm)
Product Length: 24.3" (617 mm)
Product Weight: Varies with equipment
Product Width: 13.25" (337 mm)
Radio: Included
Rear Track: 13.25" (336mm)
Receiver: Included
Scale: 1/10
Servos: Included
Shock Type: Oil-filled aluminum body
Speed Control: Included
Spur Gear: 40T
Suspension: Independent
Technology: Smart
Track: 13.25" (336mm)
Vehicle Type: Rock Racer
Water-Resistant: Yes
Wheelbase: 14.75" (375mm)

Includes:
  • (1) Lasernut U4 4WD Brushless RTR Vehicle
  • (1) Spektrum™ Firma 130A Brushless SMART ESC (installed)
  • (1) Spektrum™ 4-Pole 1900kv 550 Motor (installed)
  • (1) Spektrum™ SR6100AT Receiver with AVC
  • (1) Spektrum DX3™ 2.4GHz Radio Transitter
  • (1) Product Manual
Needed to Complete:
  • 3S or 4S Hardcase LiPo Battery with IC5/EC5 Connector
  • 3S/4S Compatible LiPo Charger
  • Protective LiPo Storage/Charging Case

This product was added to our catalog on March 8, 2021

Zer02Garage
Verified Owner
Friday, Mar 18 2022 (about 2 years ago)
Losi Lasernut U4 1/10 4WD Brushless RTR Rock Racer (Blue)
I took a bit of a risk on this purchase as the online reviews are all decently hesitant for this car. Losi called it in in a number of ways that are very deliberately hidden as ways to cut corners without being obvious in photos. The front and rear differentials are metal, but the ring only has 1/4" contact patch (on a 4s 1/7 scale!). The rear arms have so much play room that they slide back and forth on the hinge pins (that are too long for the frame, so the rear brace bends around them as it presses them into the front mounts. The front geometry is so bad that the even without the front shocks installed the arms cannot freely travel without binding. The Hinge pin mounts are anchored into plastic (and not very deep), so the first hit on the rear mount and they rip out. The body panel details (the mesh primarily) is anchored in with flimsy plastic tabs, and I lost 3 of them in the first roll over. The axles are too short for the wheels, and require locktite on the wheel nuts to not come off. The overall assembly was very loose and leaves the car as a very sloppy drive.

Now the Good, the car is beautiful to look at, it takes great photos and they did a great job replicating the 1:1. Other than that its a car whose build quality reads more $250 than $500+. I have owned other Losi products before and was really hoping that being under the Horizon hobby banner would bring up their quality. Sorry to say that that is not the case. My Lasernut required a full rebuild after one run, on the second (just bashing around a soccer field with my daughter) the rear rear assembly pulled out and now it's pretty much a useless pile of parts.

This is definitely a "parts bin" car wrapped in very pretty packaging.
john mazzanti
Verified Owner
Thursday, Jun 3 2021 (about 3 years ago)
Losi Lasernut U4 1/10 4WD Brushless RTR Rock Racer (Blue)
I didn't buy this truck for beating it on the rocks like the videos out there. i bought it to play with at our race track. the truck handles the track extremely well. Unfortunately a rim stripped out and my top light bar wasn't working with all the lights. I called Amain and he sent out a set on 2 new tires and a replacement light kit. Thank you amain hobbies for your fast response and backing your products. I love this truck and am a huge losi fan!
SHAUN CAIN
Sunday, Mar 17 2024 (7 months ago)
Losi Lasernut U4 1/10 4WD Brushless RTR Rock Racer (Blue)
I love love love the looks of this. It's absolutely the coolest looking RC i own. I disassembled the entire vehicle after driving it a few times due to center and front differentials having horrible gear mesh to the point that the gears were stripping. There was no oil in the diffs or shocks aside from a light film present on the internals. The bearings, after proper shims were added, lasted about 5 battery packs before literally falling apart. The wheel bearings overhead so bad that the stock wheels melted off the axles on 3 wheels, before i replaced the bearings initially. Afterwards i put new pro line beadlock, plastic, wheels on when i replaced the bearings with avid racing bearings. They also ended up melting from the heat generated along with the plastic hubs. I replaced the drivetrain with tekno m6 cvd, tt pro upgraded steel diffs, aluminum hubs and aluminum wheels. I also have issues with the shocks but that's more my fault for driving this like a rock racer. Oh wait, it is a rock racer. Lol
The other really big issue is with the steering assembly. Bushings instead of bearings is lame so i replaced the steering setup with Exotek aluminum and bearing instead of bushings. Even using loctite i can't keep the steering together long enough to last 1 battery pack. After the stock electronics, servo esc & motor, died they were upgraded. The stock servo was weak as expected but not terrible but the motor just couldn't handle 3s with 16t pinion and lasted about 13 battery packs. I really like this RC but it's just terribly designed and unreliable, making it very disappointing to own and also very expensive. If they made a v2 with 1/8th scale drivetrain, larger bearings etc., this would be an amazingly cool looking and fun RC. As it is, i think my lemon, along with the mini B pro roller, are the 2 worst RC cars I've ever owned and had made me make the move to Tekno RC for their durability. I wouldn't recommend this to anyone that wants to drive as intended, on the ground, flat out fun off-road buggy, for to durability issues.
John Hermans
Verified Owner
Thursday, Mar 31 2022 (about 2 years ago)
Losi Lasernut U4 1/10 4WD Brushless RTR Rock Racer (Blue)
Great truck.bigger than most 1/10 but a sweet piece to have.great on 3s. Love it so far
Peter Headley
Sunday, Sep 1 2024 (9 weeks ago)
Losi Lasernut U4 1/10 4WD Brushless RTR Rock Racer (Blue)
Kia Ora Everyone
I've only my buggy a short time. This would be the best out of the box RC I have ever owned. Its fast and tough. So far the only thing I have is a twin cooling fan. We are just coming out of winter with day temps only at 14-19c. The motor was getting quite hot. Haven't had a lot of time due to work. Anyone who wants a cool buggy this is it. Thats why it gets five stars, also five stars to Amain for there service.
Cheers Kiwi Pete
Down under New Zealand
Mark Monteiro
Verified Owner
Friday, Apr 19 2024 (6 months ago)
Losi Lasernut U4 1/10 4WD Brushless RTR Rock Racer (Blue)
Truck looks great. Build quality is great.

The steering doest work. It turn to the left but only turns half way to the right.

All all 4 wheels need shims and wheel hex is barely holding the wheel. I haven’t even run the truck yet as I'm afraid they may all strip.

The brake needs to be changed too as ilthe truck barely stops. So will have to re calibrate.


Didn't expect this from losi. I have 2 sbr's and they great.
Will Gunter
Verified Owner
Wednesday, Apr 17 2024 (6 months ago)
Losi Lasernut U4 1/10 4WD Brushless RTR Rock Racer (Blue)
After owning this for over a week now and taking it out a few times, it’s alright. Honestly I bought it because it was the super special for truck month in March and the $190 off got me. That being said, if I paid full price for it I would be very disappointed. Just like the disappointment of buying a DBXL-E 2.0. For the normal price of these Losi’s there should be no need to upgrade so much to make it last through the day. I bought an Arrma Typhon 3s at the same time as I bought this. Because of the sale of this, the typhon 3s was actually more money than the Losi by about 20 bucks. I can say that the Typhon is a much better RC then the Losi out of the box. I also bought this after reading many reviews and watching many videos so I went into it knowing that I would be spending more on it in the future. I also think the spare tire on the back is horrible looking. Looking at pictures online it looked cool, but in real life it’s a bit much.
Graham Quick
Verified Owner
Sunday, Aug 14 2022 (about 2 years ago)
Losi Lasernut U4 1/10 4WD Brushless RTR Rock Racer (Blue)
Love this car. The way it looks and drives, not a basher by any means. Probably my favourite RC car. Spares well priced and readily available hopefully won't need them.
Luke Francis
Verified Owner
Thursday, Jul 14 2022 (about 2 years ago)
Losi Lasernut U4 1/10 4WD Brushless RTR Rock Racer (Blue)
Very nice looking RC car. It's performance is weak for the $500+ price point. I'm actually disappointed, I figured I'd take it out for the first time on 4S . I set the end points,turned the punch to max and gave it a go. Needless to say I was disappointed, not only in speed and power, but the steering was week and the stock servo stripped the very first time out on the trail, the motor cogs alot at slow speeds and it gets ridiculously hot, so a fan would have been a great addition, and I'm surprised it didn't come with one for $500+ . Anyway I drove it once and now it can't turn. So it sits on the shelf. I have to buy a replacement servo now which is very disappointing considering how much this thing cost.I give it 2.4 stars only because it looks so nice and the licensed tires are pretty cool too. The lights are also nice, except the top light bar has nothing to protect the LED strip, so when you flip it takes all the abuse and turns into a shovel in the rocks potentially destroying the LED strip. Overall it's a great looking truck with a cool name but way underwhelming in power,speed and could use some beefier parts including the servo. Definitely overpriced, even for a licensed RC.
Steven Silva
Verified Owner
Wednesday, Mar 16 2022 (about 2 years ago)
Losi Lasernut U4 1/10 4WD Brushless RTR Rock Racer (Blue)
Great RC. I am having a blast with it. Naturally, it is not indestructible. I already broke a rod end by hitting a wall at an angle. I ordered the front bumper (from amain naturally). My son likes it too.
Kathleen Fisher
Verified Owner
Sunday, Oct 3 2021 (about 3 years ago)
Losi Lasernut U4 1/10 4WD Brushless RTR Rock Racer (Blue)
so far have not ran it hard but looks great and runs great