// Chassis Setup Guide

Reflex RX28
Setup Sheet

Suspension geometry, gearing, tires, and electronics for the RX28 on RCP foam tile at Super G Raceway. RCP provides higher and more consistent grip than carpet — settings are tuned accordingly. Use these as a starting baseline and dial in from there.

Chassis Specs
Scale
1/28
Mini touring car
Wheelbase
~98mm
Fixed
Track Width
~68mm
Front & rear
Motor Mount
1626
Inline rear motor
Gear Pitch
64P
53T spur / 14T pinion stock
Battery
2S LiPo
Inline fit
Base Setup — Super G Indoor Carpet
RCP Foam Tile baseline. These are known-good starting points for Super G's RCP surface. RCP grips harder and more consistently than carpet — expect to run stiffer suspension, higher brake force, and harder tire compounds than you would on carpet. Track temp matters: cold days reduce grip noticeably on foam. A rubbered-in track (mid-session) grips more than a cold clean track at the start. Log your changes between sessions.
Category Item Setting / Value Notes
Electronics
ESC Speed Controller Hobbywing Mini28 See ESC Guide for all programming settings
Motor Type 1626 Brushless Sensored Run sensored cable for smooth low-speed response
Servo Type Stock RX28 Servo BEC set to 6.0V — verify before running HV servo
Battery Pack 2S LiPo (7.4V) High-discharge preferred; ESC cutoff set to Auto (6.6V)
Radio Receiver 2.4GHz Surface RX Throttle D/R and curve at 100% default before ESC calibration
Gearing — 2500KV Class, Stock 64P
Gearing Gear Pitch 64P Standard 64 pitch gearing for the RX28. Don't mix pitch between spur and pinion
Gearing Spur Gear 53T (stock) Stock spur for 2500KV class. Larger spur = more torque, cooler motor; smaller = more top end
Gearing Pinion 14T (stock) Stock pinion for 2500KV class. FDR = 53÷14 = 3.79:1. Good baseline for Super G RCP layout
Gearing Final Drive Ratio 3.79:1 (14T / 53T) Stock FDR for 2500KV on RCP. If motor runs hot, go smaller pinion (13T = 4.08:1). If car feels slow on straights, try 15T = 3.53:1
Gearing Mesh Slight drag, no slop Too tight = heat and wear; too loose = chatter and stripped teeth
Suspension — Front
Front Suspension Ride Height 1.5 – 2.0mm Lower = more stability. Raise if bottoming on bumps
Front Suspension Camber 0° to -1° Start at 0° for carpet. Slight negative if front washes in corners
Front Suspension Toe 0° (neutral) Toe-out increases turn-in; toe-in adds straight-line stability
Front Suspension Caster Stock More caster = more steering return-to-center and stability
Front Suspension Spring Medium–Stiff RCP's higher grip generates more cornering load — stiffer springs resist roll better than on carpet. Go softer only if front is washing early in corners
Suspension — Rear
Rear Suspension Ride Height 1.5 – 2.0mm Match front ride height for balanced handling
Rear Suspension Camber 0° to -0.5° Slight negative helps rear traction on corner exit
Rear Suspension Toe +1° to +2° toe-in Rear toe-in adds stability and reduces snap oversteer
Rear Suspension Spring Stiff RCP rewards a stiffer rear — the surface provides mechanical traction so you don't need a soft spring to dig in. Stiffer = more consistent, less squat under power
Tires — Front
Front — Club Standard PN Racing KS1038 KS Compound · Medium · 8.5mm Slick The proven front choice at Super G. Medium KS compound warms up well and offers consistent lap-over-lap feel on RCP. Grips better as it heats up — long race life
Front — Alternative (PN) PN Racing KSM138 KS-M Compound · Medium · 8.5mm Low Profile Slick KS-M compound warms up faster than standard KS — good for cold mornings or short race formats where you need grip from lap 1. Similar overall performance ceiling to KS1038
Front — Alternative (PN) PN Racing KS1034 KS Compound · Soft · 8.5mm Slick Step softer from the 1038. More front bite on low-grip conditions or cold tile. Wears faster. Good option when track hasn't rubbered in yet
Front — Alternative (Reflex) Reflex Racing RX604-40 40° Low Profile Slick · 8.5mm Reflex's front slick for RCP. Developed to match the grip envelope of their 30° rear radials. Tough, long-lasting rubber. True to 22.7–22.8mm for best results — may feel aggressive mid-corner while breaking in
Front — Tire Notes Width 8.5mm (narrow) All RX28 front tires are 8.5mm narrow. Don't mix rear (11mm/14mm) width on the front — won't fit correctly and changes handling dramatically
Tires — Rear
Rear — Club Standard Marka V1 MZR-V1RR05 5° · Very Soft · 11mm Radial Softest Marka V1 rear. Maximum traction on corner exit. Best for high-grip rubbered-in RCP or high-bite sessions. Consistent batch-to-batch performance. Long life — tires continue performing well past visible tread wear
Rear — Club Standard Marka V1 MZR-V1RR10 10° · Soft · 11mm Radial The most versatile Marka V1 rear at Super G. Works across a wide grip range. Good balance of traction and stability — less edge than the 5° but much more forgiving across varying track conditions
Rear — Club Standard Marka V1 MZR-V1RR15 15° · Medium · 11mm Radial Best for low-grip RCP (cold/dusty tile) or when the 10° feels too aggressive on exit. More rotation available mid-corner. Also good if the car is already fast and you want more driver control vs. raw traction
Rear — Alt (PN Radial) PN Racing RRR10 RCP Radial Rear · 10° · 11mm PN's RCP-specific rear radial. The 10° is the closest direct equivalent to the Marka V1RR10 in the PN lineup. Good all-around RCP rear. Slightly less consistent batch-to-batch than Marka but widely available
Rear — Alt (PN PARADA) PN Racing RR1105 PARADA Rear · 5° · 11mm PN's PARADA compound rear in 5°. Similar grip range to the Marka V1 5°. PARADA compound has a different feel profile — some drivers prefer it for its consistency across the full run length. Direct swap for the Marka 5°
Rear — Alt (PN KSM Radial) PN Racing KSM220 KS-M Compound · Super Soft · 11mm Radial KS-M compound rear radial — fast warm-up, good for cold track conditions. Super Soft compound makes this closest to the Marka 5–10° range in feel. Available in Super Soft / Soft / Medium / Firm for different grip conditions
Rear — Alt (Reflex) Reflex Racing RX602-30 30° Radial · 11mm Reflex's own RCP rear radial. Non-directional tread pattern cut into a slick — tread flexes less for stability under load. Performs well once worn past visible tread. Bridges the gap between the Marka 10° and 15° in feel. 14mm version (RX603-30) available for wider rear stance
Rear — Degree Guide Choosing a compound Lower ° = Softer = More grip 5° = very soft / max traction (high-grip sessions, rubbered-in track). 10° = soft / versatile (most conditions at Super G). 15° = medium / more rotation (cold/dusty tile, or drivers who prefer less rear bite). The degree number is compound hardness — lower is grippier
Rear — Tire Notes Width 11mm standard · 14mm wide 11mm is the standard rear width for RX28. 14mm rears (Marka V1RR-14, Reflex RX603-30) add more contact patch and stability at the cost of slightly less rotation — good for modified class or high-speed RCP layouts
Tires RCP Side Textured (high-grip) Super G runs the textured/high-grip side. Smooth side = lower grip for drift formats. If a tile is flipped, you'll feel a grip hole in that section
Tires Prep / Additive Clean only — NO additive Never use tire additive on RCP. It transfers to the foam and permanently contaminates the surface, killing grip for everyone. Marka tires are additive-free rubber by design
Tires Gluing Full bead glue — all four Debeading at race speed destroys a run and can wreck the car. Glue full bead on all four tires before every race day. CA glue, thin viscosity, run all the way around the bead edge
Chassis & Body
Chassis Tweak / Flex Check flat on glass Twisted chassis = one side always lifts. Fix before tuning anything else
Chassis Weight Balance ~50/50 F/R target Battery position is your main lever. Forward = more front grip
Body Fit No chassis contact Body rubbing the chassis at speed causes binding — trim clips as needed
RCP Surface Notes
ConditionWhat HappensWhat to Do
Cold track / morning session RCP foam grip is temperature-sensitive. Cold tiles (below ~70°F / 20°C) significantly reduce grip compared to a warmed-up track. The car will feel looser and less planted early in a session. Softer tire compound, reduce throttle rate by 2–3 points, add 2–3% softening value until the track comes up to temp
Rubbered-in track (mid-session) As rubber deposits build on the RCP surface, grip increases. A "rubbered-in" track is faster and grippier than a fresh clean one. Expect the car to feel progressively more planted through a race day. You may be able to increase throttle rate and brake force as the session progresses. Don't set up for end-of-day grip and expect it to work in qualifying
Dusty / dirty tile Dust on RCP acts like marbles — it drastically cuts grip and makes the surface unpredictable. Debris (dirt, hair, grit) embeds in the foam and stays there until cleaned. Don't walk on the track surface — shoes transfer oils and grit. If grip suddenly drops mid-session, look for debris. Wipe with a damp microfiber cloth.
Textured vs smooth side RCP tiles have two sides. Textured (high-grip) is the racing surface at Super G. Smooth (low-grip) is used for drift-oriented sessions. If a tile gets flipped, you'll notice a dramatic grip loss in that section of track. If one section of track suddenly has no grip, check if a tile is flipped. Notify track staff — a flipped tile is a hazard for all cars on track.
Tire additive Tire additive (traction compound) applied to tires will transfer to RCP foam and permanently contaminate the surface — killing grip for everyone. Super G and most RCP venues prohibit additive entirely. Never apply tire additive at a venue running RCP. Use compound selection to tune grip — not additive.
Condition Adjustments

Select a condition to see what to adjust from the RCP base setup.

High Grip
Rubbered-in RCP, warm session, peak traction
Low Grip
Cold tiles, dusty track, morning session
Fixing Oversteer
Rear stepping out, snapping on exit
Fixing Understeer
Car pushing wide, not rotating on entry
Blinky Class
Zero timing, stock power rules
Modified Class
Boost and turbo timing allowed
ItemAdjustmentWhy
Throttle Rate (2A)+3–5 pointsRubbered-in RCP handles more aggressive power delivery — you can exploit the extra grip
Softening Value (2F)Reduce by 2–3°High grip RCP supports more direct bottom end — less softening needed
Max Brake Force (3B)+5–10%More grip = later, harder braking available without locking up
Drag Brake (3A)+2–3%High-grip RCP absorbs more drag brake — helps rotation on corner entry
Front SpringGo stifferMore grip generates more cornering load — stiffer spring keeps the car flat
Rear TireCan go slightly harder compoundExtra grip means a harder rear still has plenty of traction — longer wear life too
ItemAdjustmentWhy
Throttle Rate (2A)-3–5 pointsCold or dusty RCP is much slipperier — smoother power delivery prevents wheelspin
Softening Value (2F)+5–8°Milder bottom end gives you more control when the foam grip is down
Softening Range (2G)Increase to 40–50%Widen the softening zone to cover more of the corner exit phase
Drag Brake (3A)Reduce to 3–5%Less drag brake reduces rear snap on turn-in when grip is low
Max Brake Force (3B)-10–15%Less brake force prevents lock-up on cold or dusty foam
Tire CompoundGo softer all aroundSofter compound generates more heat and bite when the RCP surface is cold — key for cold morning sessions
Track temp checkWait for warm-up lapsRCP grip increases significantly as the track warms and rubbers in — don't judge final setup from the first pack of the day
ItemAdjustmentWhy
Throttle Rate (2A)Reduce by 3–5Smoother power on exit = rear doesn't break away
Softening Value (2F)Increase by 3–5°Milder initial throttle = more control out of corners
Drag Brake (3A)Reduce or go to CoastHigh drag brake can snap rear on quick direction changes
Rear ToeIncrease to +2°More toe-in adds rear stability and reduces snap oversteer
Rear SpringGo stifferStiff rear reduces squat and snap under power
Rear CamberAdd 0.5° negativeMore camber = more rear contact under load
Rear TireGo harder compoundLess rear traction = less snap oversteer tendency
ItemAdjustmentWhy
Drag Brake (3A)Increase by 3–5%More drag brake helps rotate the car on entry
Max Brake Force (3B)Increase by 5–10%More braking rotates car into corners
Front CamberAdd 0.5–1° negativeMore front camber = better front grip on corner entry
Front SpringGo softerMore front flex = more front grip and better turn-in
Front ToeSlight toe-out (0.5°)Toe-out sharpens initial turn-in
Rear ToeReduce to +0.5–1°Less rear toe-in allows more rotation
Weight BalanceBattery forwardMore front weight = more front grip
ItemSettingNotes
Boost Timing (4A)0° — mandatoryAny value above 0° is illegal in blinky class
Turbo Timing (5A)0° — mandatoryAny value above 0° is illegal in blinky class
Throttle Rate (2A)10–12Less power available = smoother rate still helps traction
PWM Frequency (2E)8KConsistent with base setup
Softening Value (2F)8–10°Higher softening compensates for limited power ceiling
GearingSlightly taller FDRWithout timing, FDR is your primary speed lever — run taller than modified
Motor TimingStock / low mechanicalLower mechanical timing stays cooler; no boost to supplement it
ItemSettingNotes
Boost Timing (4A)10–20°Start low. Add 2° at a time and check motor temp between runs
Boost Activation (4B)RPM modeMore progressive than Auto; easier to drive
Boost Start RPM (4C)10,000–12,000Above corner exit RPM — boost should fire on straights
Boost End RPM (4D)20,000–25,000Full timing above this threshold
Turbo Timing (5A)0–10° (optional)Only useful if Super G has a significant straight. Watch heat.
Turbo Delay (5B)0.2–0.3sPrevents accidental turbo in chicanes
GearingShorter FDR vs blinkyTiming adds top RPM — you can gear shorter and let timing pull top speed
Motor Temp TargetUnder 65°CCheck with heat gun after first hot lap. Back off timing if over.
Session Log Template
Track your changes each session so you know what works. Print this or keep a notes app open at the track.
DateTrack ConditionKey Changes MadeResult / Notes
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