1/10 Scale Electric Buggy:

Losi Lasernut U4 Rock Racer - LOS03028T1 - Radio Controlled Buggy

Navigation:

History and Info:

Released by Losi in 2020, the Lasernut U4 2.2 Electric Rock Racer Buggy - LOS03028T1 - was available factory assembled RTR, with a pre-painted Black/Blue Bodyshell, Spektrum Firma 4-Pole 1900Kv 550 Brushless Motor, 130A Smart ESC, AVC (Active Vehicle Control) SR6100AT Receiver, Servo and DX3 2.4Ghz Radio Transmitter. A Battery and Charger to be purchased separately.

The 4WD model is shaft driven, on a 3mm alloy plate chassis, with gear type differentials, coil spring over oil filled dampers, sway bars, universal joint drive-shafts and a full set of ball bearings.

Losi Lasernut U4 Rock Racer Buggy - LOS03028T1

▼ Scroll Down for More Images ▼

To get the best from the Losi Lasernut U4, it needs to be fine tuned, to provide precise steering response and improve grip when cornering, so you don't slide off the track. Small changes can make huge advancements and our easy to understand guide will help you to the optimum Set-up for your individual driving style.

Lasernut U4 Rock Racer - LOS03028
Instruction Manual

Lasernut U4 Rock Racer - LOS03028
Parts and Exploded View

CHECK AVAILABILITY
On Amazon

Radio Controlled Model Accessories:

★ Losi Lasernut U4 Rock Racer ★

★ Losi Lasernut U4 Rock Racer Chassis ★

Buying a Used Losi Lasernut U4
Buggy (and What to look for)

There are essentially three reasons you might want to buy a used Losi Lasernut U4 Electric Buggy; you may be a collector, looking to restore and display it; restore and sell for a profit; or simply restore and race an iconic vintage model. Personally, I used to get a buzz out of restoring an old clapped-out model, installing modern day electrics and maybe a few hop-ups, then showing the gang at our local club, just how competitive those old models could still be.

Cheap, pre-loved bargain models, parts and spares are always coming up for sale, but once you have made your purchase, the one thing you will always need, is an instruction manual. If not supplied with your purchase, they can often be downloaded from the Losi website, or purchased separately on eBay. With an instruction manual, any problems with your model Buggy you may discover, can easily be fixed.

Make a General Visual Inspection

Dampers
When you receive your used Losi Buggy, make a general visual inspection of the chassis, front and rear wishbones, suspension shock towers etc, for any broken parts that may need to be replaced. Then, take a screwdriver and box spanner and check each self tapping screw and nut for security, taking care not to over tighten.

Next, for those Losi models with oil filled shock absorbers, remove them from the chassis and dismantle the coil springs. The damper shafts should push in and pull out with a smooth action. If you feel a jolt as you change direction, this means the oil has leaked out and must be topped up. At the same time, change the O-Ring seals to prevent more leakage. Also check the damper shafts for damage. If they are scratched, change them as soon as possible.

Check the Body-Shell

If the body shell of your Losi Lasernut U4 is broken, ripped or damaged in any way, this can be easily repaired with rubber solution glue. Also, for added protection and if available for your Lasernut U4 model, fit an under guard to stop dirt and gravel entering the chassis.

Drive Shafts and Turnbuckles

Titanium Turnbuckles
Examine the drive shafts for wear and replace as required. If possible, change them for titanium. The steel shafts wear and bend too easily.

If you intend to race your Lasernut U4 Buggy model at a competitive level, I would also recommend you obtain and fit titanium pivot shafts, turnbuckles, tie rods and steering rods.

Examine the Drive System

The gearbox of your used Buggy should be opened up to check for gear wear and lubrication. A thin coat of grease is often used on internal gears and although this is fine for basic running around on the back yard, if you intend to race your Buggy at a higher level, this should be removed and replaced with racing oil (ZX1 or Teflon Oil). Of course, this should be reapplied after each race meeting.

Pinions and Spur Gears

Gears are a weakness on all Buggy RC models. Head on collisions can easily damage the gear teeth on nylon and plastic spur gears. Heavy impacts can also loosen the nuts or self tapping screws that hold the Electric Motor in Position, allowing the pinion gear to pull out of mesh slightly and rip the tops off the teeth on your spur gear. To minimise this possibility, fit bolts with locking nuts to the Electric Motor mount and remember to check them for security after every two or three runs.

Don't Neglect the Ball-Joints

Ball joints always cause problems. For top level Electric Buggy racing, the plastic ball connectors should be checked and if deemed necessary changed after every meeting. A simple thing like a loose fitting connector popping off could easily end your race, so better safe than sorry.

Steering Servo and Servo-Saver

Servo Gears
The Lasernut U4 steering servo is also prone to damage. In high speed crash situations, the fragile gear teeth of the servo can be broken off, rendering your expensive servo useless, so be sure to obtain a good quality "Servo Saver". Check out my Servo Information article.

Stabilizers

If body roll on your Losi Lasernut U4 is a problem, handling can be improved with the use of stabilizers, anti roll or sway bars, stiffer tuning springs and, or, thicker silicone oil in the dampers.

Don't Forget those Bearings

If your used Losi Buggy comes with plastic and sintered brass bushings (ring type bearings), check the shafts that run in them for wear. Dust and grit can get into these bearings and abrade the shafts. Therefore, you should replace them all with shielded ball bearings. If the model has been run with ring type bearings, you may have to change all the axles and driveshafts. For more information, take a look at my article, How to get the best from your Bearings.

Finally, good luck with your Lasernut U4 model and good racing.

▼ Scroll Down for More Articles and Advice ▼

Or, check out our RC Model Car Setup Guide

^ TOP ^

Manufacturers and Brands Catalogued, Listed and Reviewed by RC-Scrapyard.

At present, the RC Model Manufacturers, Brands and Distributors covered by us are: ABC Hobby, Academy, Acme Racing, Agama Racing, Amewi, Ansmann Racing, ARRMA, Team Associated, Atomic RC, Axial, AYK, Bolink, BSD Racing, Capricorn, Carisma, Carson, Caster Racing, Cen, Corally, Custom Works, Durango, Duratrax, ECX - Electrix, Exceed RC, FG Modellsport, FS-Racing, FTX, Fujimi, Gmade, GS-Racing, Harm, HBX, Helion, Heng Long, Himoto Racing, Hirobo, Hitari, Hobao, Hong-Nor, Hot Bodies, HPI, HSP, Intech, Integy, Jamara, JQ Products, Kawada, Kyosho, Losi, LRP, Maisto, Mardave, Marui, Maverick, MCD Racing, Megatech, Mugen, New Bright, Nichimo, Nikko, Nkok, Ofna, Pro-Pulse, Protech, PTI, RC4WD, Redcat Racing, RJ-Speed, Robitronic, Schumacher, Seben, Serpent, Smartech, Sportwerks, Step-Up, Tamiya, Team-C Racing, Team Magic, Thunder Tiger, Tomy, Top Racing, Traxxas, Trinity, Tyco, Vaterra RC, Venom, VRX Racing, WLToys, X-Factory, Xmods, Xpress, Xray, XTM, Yankee RC, Yokomo, ZD Racing and Zipzaps.

This is an ongoing project, with new and "lost in time" RC Models and Brands being added as they are found and although most of those listed above have been covered in relative detail, some are still being researched and will be completed in the near future.

RC Information and Advice:

Hints, Tips and Information

Painting a Lexan Body Shell.

   Most RC Model kits come with an unpainted, clear Lexan plastic Body Shell you yourself must prepare and paint. This type of Body Shell is painted on the inside, and special spray or brush on Polycarbonate Paints MUST be used.

   The beauty of this is you can go wild and show off your artistic ability, or simply choose your favourite colour, and add some choice decals later.

   This article is for those who have never done this kind of thing before, and need some basic guidance.

   Firstly, cut off the waste from the body shell with sharp scissors. If required finish off the rounded wheel arches with smooth sandpaper wrapped around a drinks can.

   Any holes for body posts must also be drilled before painting. Place the clear body shell over the model and adjust the posts so the shell is in the desired position. Where the posts touch the shell make a small dot with a marker pen.
Next, pierce small holes in the shell where the dots are from the inside. Place the shell on an old piece of wood and drill the post holes, again, from the inside.

Read the Complete Article ▶ ▶

Hints, Tips and Information

Radio Frequencies - be Careful be Safe

   After buying your first car, it won't be long before you need more than simply bashing around the back yard, or out on the street. So you will be looking around to find a club that is not too far away where you can do some serious racing.

   Before you can start racing, you will need at least three different sets of crystal frequencies. The race organisers will note down all your available frequencies when you register at the track and allocate one of those frequencies to you for your heat. To avoid change over problems from one heat to the next, they generally try to give you a frequency that no one in the heat before or after is using, but always check to make sure before you put your car down on the track and switch on.

   There is nothing more annoying than to be in the middle of your best qualifying race and some idiot switching on their transmitter in the pits, on your frequency. Not only could it spoil your race, but it could cost you a lot of money if at the time you are travelling at top speed along the straight, loose control and crash head on into the wall.

Read the Complete Article ▶ ▶