Rear-Axle Bias Control
Designed to support stable trail braking, corner entry behavior, and rear brake balance without overpowering the front axle.
Pay in installments of $286.25 with
,
and
Shipping Estimate
USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Aug 9 - Aug 14
Promo Codes Available:
For Your Every Summer RSVP, with Code: SUMMER15
Description
Circuit Racing TR49 Rear Wheel 4-Piston Big Brake KitRacing Series Circuit Rear Axle 4 Piston TR49 Circuit Racing Rear 4 Piston Big Brake Kit The Circuit Racing TR49 is a rear axle 4 piston big brake kit built for circuit work, time attack, and endurance use. A monoblock forged caliper, two piece floating rotors, and racing pad compounds deliver consistent pedal feel and thermal repeatability lap after lap. Why Builders Choose the TR49 Rear brake balance is what keeps a chassis stable under trail
Racing Series · Circuit · Rear Axle · 4-Piston
TR49 Circuit Racing Rear 4-Piston Big Brake Kit
The Circuit Racing TR49 is a rear-axle 4-piston big brake kit built for circuit work, time attack, and endurance use. A monoblock forged caliper, two-piece floating rotors, and racing pad compounds deliver consistent pedal feel and thermal repeatability lap after lap.
Why Builders Choose the TR49
Rear brake balance is what keeps a chassis stable under trail braking and corner entry. The TR49 pairs 28 mm and 34 mm staggered pistons with a 30.80 cm² total piston area to give a controllable rear bias without overpowering the front. Combined with a 355 or 380 mm rotor, it lets you dial in proportioning for slicks, R-comps, or street tires.
Monoblock Forged Caliper
Monoblock forged aluminum caliper, 2.40 kg per side, built for stiffness and repeatable pedal response.
Staggered 4-Piston Bore
28 mm × 2 and 34 mm × 2 piston layout supports even pad wear and progressive bite.
Racing Piston Package
Racing pistons without dust boots are designed for high-temperature service and fast race-weekend inspection.
Two-Piece Rotor Platform
Ø355 or Ø380 mm × 32 mm two-piece internally vented rotors with directional vanes.
Race-Weekend Serviceability
Replaceable iron rings, top-access pad changes, open-back pistons, and accessible bleeders support real pit workflow.
Technical Specifications & Kit Options
| Brake Caliper | ||
|---|---|---|
| Series | Racing Series — Circuit | |
| Model / Application | TR49 | |
| Axle Position | Rear | |
| Piston Count | 4-piston | |
| Piston Type | Racing pistons without dust boots | |
| Piston Diameter | 28 mm × 2 / 34 mm × 2 | |
| Caliper Dimensions | 258.8 mm × 157.7 mm × 75.2 mm | |
| Total Piston Area | 30.80 cm² per caliper | |
| Manufacturing Process | Monoblock forged aluminum body | |
| Net Weight | 2.40 kg per caliper, without pads | |
| Surface Finish | Nickel-plated | |
| Custom Color | Not available on this caliper | |
| Recommended Wheel Size | 18 in or larger | |
| Recommended Rotor Size | Ø355–380 mm × 32 mm | |
| Brake Rotor Options | ||
| Rotor Option | Standard | Option B Racing |
| Rotor Material | Heat-treated high-carbon cast iron | Racing-grade heat-treated high-carbon cast iron |
| Axle Position | Rear | Rear |
| Rotor Dimensions | Ø355 / 380 mm × 32 mm | Ø355 / 380 mm × 32 mm |
| Construction | Two-piece rotor assembly | Two-piece rotor assembly |
| Ventilation | Internally vented | Internally vented |
| Rotor Hats | Application-specific alloy rotor hats | Application-specific alloy rotor hats |
| Rotor Mounting | Fixed or floating, by size and application | Fixed or floating, by size and application |
| Directional Design | Yes — left/right specific | Yes — left/right specific |
| Rotor Face Pattern | Curved slotted / Grain Slot / Wave Slot / Drilled and slotted | Wave Slot |
| Brake Pad Options | ||
| Pad Option | Standard | Option B Racing |
| Compatible Rotor Material | Iron / steel rotors only | Iron / steel rotors only |
| Operating Temperature Range | 0–600 °C | 0–750 °C |
| Average Friction Coefficient | μ ≈ 0.38, varies with temp, pressure, rotor | μ ≈ 0.45, varies with temp, pressure, rotor |
| Best Use | HPDE, autocross, aggressive street use | Sustained circuit and endurance sessions where heat soak is the limiting factor |
| Lines, Brackets & Service | ||
| Brake Line Construction | Three-layer reinforced | |
| Brake Line Material | PTFE inner liner / SUS304 stainless braid / PVC outer sheath | |
| Caliper Mounting Type | Radial mount with vehicle-specific caliper brackets | |
| Caliper Brackets | Vehicle-specific caliper brackets | |
| Brake Line Fitting Type | Vehicle-specific; caliper-side and chassis-side fittings vary by application | |
| Bedding-In Procedure | Required before track use | |
Rear pad selection should typically run a half-step softer or cooler than the front to maintain stable rotation under brake. Match Option B rear pads with similar or higher-temp front pads to keep the car balanced.
Package List
Calipers ×2
2 × TR49 rear monoblock forged 4-piston calipers with nickel-plated finish.
Brake Pads
Brake pads for both rear calipers, selected from 0–600 °C standard compound or 0–750 °C Option B racing compound.
Brake Rotors ×2
2 × two-piece internally vented rear rotors, Ø355 or Ø380 mm × 32 mm, left/right specific.
Caliper Brackets ×2
Vehicle-specific radial caliper brackets for correct rear caliper alignment.
Rotor Hats ×2
Application-specific alloy rotor hats matched to rear hub location and rotor offset.
Brake Hoses ×2
Three-layer stainless-steel braided rear brake lines with PTFE inner liner, SUS304 braid, and PVC outer sheath.
The Bespoke Engineering Process
Every TR49 rear circuit racing system is engineered around the vehicle’s rear knuckle, hub location, rotor hat offset, wheel barrel, spoke clearance, brake line routing, parking brake provision, and front-to-rear brake balance target. The goal is not a generic universal fit; the goal is a rear brake package that works with your chassis geometry and gives the driver repeatable pedal behavior under trail braking, corner entry, and long-session heat.
1. Technical Consultation
We review the chassis, rear suspension and knuckle setup, competition use, target rear brake behavior, front brake pairing, wheel package, tire compound, ABS / proportioning strategy, parking brake requirement, and whether the car uses OEM or custom rear uprights.
2. Data Submission
For OEM knuckles, provide the vehicle information, wheel specs, wheel offset, and spoke clearance data. For custom knuckles, motorsport hub conversions, or non-OE rotor offsets, provide CAD files, drawings, hub-face data, rotor mounting dimensions, or accurate bracket mounting-point measurements.
3. Engineering Review & Approval
TTSPORT reviews the submitted data, confirms caliper clearance, vehicle-specific caliper bracket geometry, rotor hat offset, parking brake approach, and brake line routing before production begins.
If you are unsure whether your wheel, rear knuckle, rotor offset, parking brake layout, or brake line routing is suitable, Contact us before ordering so the engineering team can review the build details.
Installation & Break-In
- Every TR49 rear kit ships with vehicle-specific caliper brackets and brake lines.
- Two-piece rotors allow iron ring replacement without buying new hats.
- Pads change from the top with a single retainer pin.
- Open-back pistons allow fast inspection and seal service.
- Standard race fluid bleeders are accessible with the caliper on the car.
- Confirm wheel offset, spoke profile, hub specs, rotor offset, and line routing before production.
- A proper bedding procedure is required to transfer pad material evenly to the rotor face before track use.
Frequently Asked Questions
Will the TR49 rear kit clear my wheels?
The kit requires an 18-inch or larger wheel. Clearance also depends on wheel offset and spoke profile. Send your wheel specs with your order and we'll confirm before shipping.
Should I match this with a TTSPORT front BBK?
Yes. Rear-only upgrades can shift bias rearward and cause instability. Pair the TR49 with a matching front kit sized for your vehicle to keep brake balance correct.
Which rotor size should I choose, 355 or 380 mm?
Ø355 mm is the lighter, more wheel-friendly option and works for most rear setups. Ø380 mm adds thermal capacity for endurance and heavier cars where the rears do more work.
Do I need to bed the pads in?
Yes. A proper bedding procedure is required to transfer pad material evenly to the rotor face. Skipping it causes judder, uneven deposits, and reduced pad life.
Can the calipers be color-customized?
The TR49 ships in nickel-plated finish. Custom color/anodizing is not available on this caliper.
Does the kit include parking brake provision?
The TR49 is a service-brake caliper. Vehicles with integrated rear parking brakes typically retain the OEM e-brake setup via drum-in-hat rotors or a separate e-brake caliper, depending on application. Confirm with our team for your specific car.
Build Your TR49 Rear Kit
Send your vehicle and wheel details and we'll spec the right rotor size, pad compound, rotor hat offset, and bracket package for your program.
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy
4.5 ★★★★★
Based on 10 reviews
Sort
Product Reviews
★★★★★ 5
Tan lines
Size: 6.7 Fl Oz (Pack of 1)
This sunscreen works great. It’s light and doesn’t feel greasy on your skin. I use it all the time.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 22, 2026
★★★★★ 5
Lightweight glowing hydrating sunscreen
really love how this sunscreen feels so light and smooth on my skin without leaving any white cast at all. It blends in quickly and gives a natural, hydrated glow skin with hyaluronic acid and collagen. My skin feels moisturized all day, and it doesn’t get oily or greasy even after hours. It’s gentle enough for my sensitive skin and hasn’t caused any irritation or breakouts. it’s a great everyday sunscreen that keeps my skin protected and fresh.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 14, 2026
★★★★★ 5
Lightweight Sunscreen with Great Hydration
This sunscreen feels lightweight on the skin and blends in nicely without leaving a heavy or greasy feeling. I like that it gives SPF 50 protection while also adding hydration, so it works well as part of a daily skincare routine. It leaves the skin feeling soft and comfortable.
The formula sits nicely under makeup or can be worn alone for a natural look. It absorbs well and does not feel sticky, which makes it easy to reapply when needed. A great option for everyday sun protection with added moisture.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 24, 2026
★★★★★ 5
Best sunscreen
I really like this sunscreen. It feels lightweight on the skin and blends in easily without leaving a white cast, which is a big plus. The texture is smooth and moisturizing, but it does not feel oily or heavy. It works well for daily use, especially under makeup, and feels comfortable even on sensitive skin.
The SPF 50 PA++++ protection gives good peace of mind for everyday sun exposure. I also like that it has hyaluronic acid and collagen, so it feels more like skincare than just sunscreen. Overall, it is a great affordable Korean sunscreen and I would definitely recommend it.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 18, 2026
★★★★★ 5
My honest review
Lightweight Protection with No White Cast
I am very satisfied with this sunscreen. The texture is lightweight, it absorbs quickly, and it truly leaves a "no-cast" finish—without that white layer that many sunblocks tend to leave behind. Plus, it feels hydrating thanks to the collagen, so it works beautifully under makeup or on its own for everyday wear.
It offers excellent SPF 50+ PA++++ protection against UVA and UVB rays and leaves no greasy residue. The size is convenient for carrying in a bag or taking along on trips.
After using it for several days, my skin feels protected, soft, and comfortable, even in hot weather. I would definitely buy it again and highly recommend it to anyone looking for a lightweight, hydrating sunscreen with a natural finish.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 16, 2026
recommand products
Prolene Suture Cutting P Needle: 19mm 45cm Blue 1-0 1.5 x 24
132.99
Boomslang Plug and Play Harness Kit for MoTeC M150 (BF24219-M150)
399.00
Boomslang Plug and Play Harness Kit for Link G4X AtomX (BF26154-A)
302.70
Boomslang Plug and Play Harness Kit for Link G4X AtomX (BF26051-A)
302.70
Omron Wide Range Cuff
19.99