◆ Car not doing what you want?
Fix your handling.
Pick the symptom. We'll tell you what's causing it, what to change on the car, and which parts actually fix it — in that order.
Won't hold angle
Likely cause · Not enough rear rotation / too much rear grip
- Move weight forward — battery further towards the front bulkhead.
- Reduce rear tyre grip: harder compound, or widen the rear track.
- Add rear toe-in 0.5–1° for stability without killing rotation.
- Check gyro gain isn't fighting the slide — drop it 10%.
◆ Parts that fix this
Still not right? Ask us ▸
Spins out on entry
Likely cause · Too much rear rotation / not enough rear grip
- Add rear toe-in, 1–1.5°, to settle the back end.
- Soften rear springs one step so the rear squats and loads the tyres.
- Move the battery back towards the rear bulkhead for rear bite.
- Raise gyro gain 5–10% at a time until the catch feels natural.
◆ Parts that fix this
Still not right? Ask us ▸
Won't turn in
Likely cause · Front grip too low, or steering throw running out
- Check the steering end point — most kits leave 10° of unused throw at the knuckle.
- Add front camber, 1–2° negative, for more bite on turn-in.
- Move weight forward: battery, or brass on the front bulkhead.
- Fit fresh front tyres — compound goes glassy long before it looks worn.
◆ Parts that fix this
Still not right? Ask us ▸
Traction rolls
Likely cause · Centre of gravity too high for the grip level
- Drop ride height 1mm front and rear before touching anything else.
- Stiffen the sway bars, front first, to cut body roll.
- Get mass low and central — battery flat, nothing ballasted high.
- Thicker shock oil slows the rate the car rolls over.
◆ Parts that fix this
Still not right? Ask us ▸
Wheel hop under power
Likely cause · Drivetrain binding, or rear damping too stiff
- With the motor out, the drivetrain should spin freely by hand — notchiness is a bearing.
- Thinner rear shock oil so the tyres stay planted.
- Check driveshaft plunge; a shaft that binds at full droop causes hop.
- Back off rear toe slightly if you've overdone it.
◆ Parts that fix this
Still not right? Ask us ▸
Skittish over bumps
Likely cause · Damping or spring rate too stiff for the surface
- Thinner shock oil, one step at a time — 100cSt is a noticeable change.
- Softer springs before you change anything geometric.
- Add droop so the wheels can extend down into dips.
- Check for a tweaked chassis — a bound corner can't absorb anything.
◆ Parts that fix this
Still not right? Ask us ▸
Pulls to one side
Likely cause · Chassis tweak, or uneven steering geometry
- Sit the car on a flat board — both front tyres should touch with equal pressure.
- Measure both steering turnbuckles; they must be identical lengths.
- Even up ride height corner to corner with shims or collars.
- Re-centre the servo horn at trim zero, rather than dialling in radio trim.
◆ Parts that fix this
Still not right? Ask us ▸
Motor overheating
Likely cause · Gearing too tall, or airflow blocked
- Drop 2 teeth on the pinion — the single biggest fix.
- Anything over 70°C on the can needs gearing down, not more fan.
- Fit or upgrade the fan and heatsink, and check it blows onto the can.
- Check spur mesh — too tight and the motor is loaded constantly.
◆ Parts that fix this
Still not right? Ask us ▸
ESC cutting out
Likely cause · Voltage sag, or a bad connection
- Check the LiPo cut-off matches your pack — set too high and it cuts early.
- Re-solder or replace tired connectors; a warm plug is a failing plug.
- Add a capacitor pack if you're running a low-turn motor.
- Load-test the pack — a cell that sags under load reads fine at rest.
◆ Parts that fix this
Still not right? Ask us ▸
Steering slow or weak
Likely cause · Servo underspecified, or the steering is binding
- Disconnect the link — the steering should fall side to side under its own weight.
- Check for a dry or notchy steering block bearing.
- A drift car wants 0.06s/60° or faster; touring can live with less.
- Fit a metal servo horn — a flexing plastic horn feels exactly like a slow servo.
◆ Parts that fix this
Still not right? Ask us ▸
Diff feels inconsistent
Likely cause · Diff oil worn out, or the diff is slipping
- Rebuild with fresh oil — used diff oil thins out long before it looks dirty.
- Front thicker than rear for on-power stability; start 30k front, 10k rear.
- Check for a cracked crosspin or a rounded outdrive.
- On a ball diff, retighten to just before the point it slips under power.
◆ Parts that fix this
Still not right? Ask us ▸
Drivetrain noisy
Likely cause · Worn bearings, or bad gear mesh
- Set spur/pinion mesh with a strip of paper trapped between the teeth.
- Spin each wheel off the ground — a rumble is a wheel bearing.
- Check belt tension: it should deflect a few mm, not sing.
- Replace rubber-sealed bearings every few months; they're a service item.
◆ Parts that fix this
Still not right? Ask us ▸
Body rubs the tyres
Likely cause · Ride height or body posts set too low
- Raise the body posts before you raise the car.
- Trim the wheel arches — most shells ship undersized for wider offsets.
- Check wheel offset; a lower offset pulls the tyre into the arch.
- Add a spacer under the body mount if the shell sits nose-down.
◆ Parts that fix this
Still not right? Ask us ▸
Short runtime
Likely cause · Gearing too tall, or the pack is past its life
- Check pack internal resistance — anything climbing sharply is worn out.
- Gear down: a hot motor is wasted runtime.
- Storage-charge between sessions rather than leaving packs full.
- Balance-charge every time; one lazy cell drags the whole pack down.
◆ Parts that fix this
Still not right? Ask us ▸
Radio glitching
Likely cause · Antenna placement, or electrical noise
- Get the antenna tip vertical and clear of carbon — carbon blocks 2.4GHz.
- Keep the receiver away from the motor and the ESC power wires.
- Add a capacitor across the motor terminals if the glitch is throttle-related.
- Re-bind, and check for a chafed or broken antenna wire.
◆ Parts that fix this
Still not right? Ask us ▸
Tyres wearing unevenly
Likely cause · Camber or toe out of spec
- Outside edge wearing means not enough negative camber.
- Inside edge wearing means too much — back it off 0.5°.
- Feathered edges mean toe is off; check both sides match.
- Rotate tyres front to rear to even out a set.
◆ Parts that fix this
Still not right? Ask us ▸
◆ Stop guessing your pinion
Gearing calculator.
Final drive ratio decides whether your car snaps into angle or cooks its motor. Enter your gears and we'll tell you which side of the line you're on — and what to change.
◆ Your gearing
◆ Final drive ratio
—
FDR · (spur ÷ pinion) × internal ratio
Enter your gearing to see whether you're geared for angle or for heat.
◆ Free to download
Setup sheets.
Baseline numbers to start from. Start from a sheet that already works on your surface, then tune from there — it beats guessing from scratch.
Surface
Reve D RDX
- Front camber-2.0°
- Rear camber-0.5°
- Rear toe1.0° in
- Ride height6.0mm
- Gyro gain55%
- FDR7.0
- TyresTOPLINE Sport HDPE
Yokomo YD-2
- Front camber-2.2°
- Rear camber-0.5°
- Rear toe0.8° in
- Ride height5.5mm
- Gyro gain50%
- FDR6.8
- TyresYokomo DRC carpet
MST RMX 4 GT
- Front camber-2.5°
- Rear camber-0.3°
- Rear toe0.8° in
- Ride height5.5mm
- Gyro gain46%
- FDR6.6
- TyresYokomo DRC carpet
Overdose GALM
- Front camber-2.5°
- Rear camber-0.4°
- Rear toe0.9° in
- Ride height5.5mm
- Gyro gain48%
- FDR6.7
- TyresDS Racing Finix LF-5
Reve D RDX
- Front camber-1.8°
- Rear camber-0.8°
- Rear toe1.3° in
- Ride height6.5mm
- Gyro gain60%
- FDR7.5
- TyresTOPLINE Sport HDPE
MST RMX 2.5
- Front camber-2.0°
- Rear camber-0.7°
- Rear toe1.2° in
- Ride height6.5mm
- Gyro gain57%
- FDR7.3
- TyresMST PST V2 HDPE
Team AD RD2.0
- Front camber-2.0°
- Rear camber-0.6°
- Rear toe1.2° in
- Ride height6.5mm
- Gyro gain56%
- FDR7.2
- TyresMST PST V2 HDPE
Rhino Racing RTS 1/24
- Front camber-1.5°
- Rear camber-0.5°
- Rear toe1.0° in
- Ride height2.5mm
- Gyro gain65%
- FDRn/a — fixed pinion
- TyresRhino R500 POM
Yokomo YD-2
- Front camber-1.5°
- Rear camber-1.0°
- Rear toe1.8° in
- Ride height7.5mm
- Gyro gain65%
- FDR8.0
- TyresYokomo DRA asphalt
MST RMX 2.0
- Front camber-1.2°
- Rear camber-1.0°
- Rear toe2.0° in
- Ride height8.0mm
- Gyro gain68%
- FDR8.2
- TyresMST CS M low-grip
Tamiya TT-02
- Front camber-1.0°
- Rear camber-1.0°
- Rear toe2.0° in
- Ride height8.0mm
- Gyro gainn/a — 4WD
- FDR8.6
- TyresTOPLINE Street Edition
Yokomo YD-2
- Front camber-1.6°
- Rear camber-0.9°
- Rear toe1.9° in
- Ride height8.5mm
- Gyro gain68%
- FDR8.2
- TyresTOPLINE Street Soft
Reve D RDX
- Front camber-1.5°
- Rear camber-1.0°
- Rear toe2.0° in
- Ride height9.0mm
- Gyro gain70%
- FDR8.4
- TyresTOPLINE Street Soft
No sheets for that surface yet.
◆ Ask before you buy
Ask us.
Tell us the car, the surface you run on and what it is doing, and we will tell you which part actually fixes it. If something here is not right for you, we will say so rather than sell it to you.
◆ How to reach us
Opening hours
Tuesday – Friday, 10:00 – 17:00
Saturday and Sunday closed
Email
support@rcshopper.com
Tuesday – Friday, 10:00 – 17:00
Saturday and Sunday closed
support@rcshopper.com
◆ What do you need help with?