Brake Balance First
2-piston, 30.95 cm² caliper area sized to complement front BBK clamp without over-braking the rear axle or triggering early lockup.
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- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 8 - Jul 13
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Description
Circuit Racing TR20 Rear Wheel 2-Piston Big Brake KitRacing Series Circuit Rear Axle 2 Piston TR20 Rear 2 Piston Racing Big Brake Kit The TR20 is a lightweight 2 piston rear racing caliper built for teams that need rear brake contribution to be consistent, measurable, and tunable. In a proper motorsport package, the rear axle is not judged by peak clamp alone it has to support the front, hold bias, and keep the pad compound window usable across a full session. Built around a two piece forged aluminum
Racing Series · Circuit · Rear Axle · 2-Piston
TR20 Rear 2-Piston Racing Big Brake Kit
The TR20 is a lightweight 2-piston rear racing caliper built for teams that need rear brake contribution to be consistent, measurable, and tunable. In a proper motorsport package, the rear axle is not judged by peak clamp alone — it has to support the front, hold bias, and keep the pad compound window usable across a full session.
Built around a two-piece forged aluminum body and racing pistons without dust boots, the TR20 is engineered for track, drift, rally, and endurance use where thermal repeatability and pedal consistency matter over repeated high-energy stops. Each kit is built through a vehicle-specific workflow so rear bias, rotor package, bracket geometry, brake line routing, and wheel clearance are confirmed before production.
Why Builders Choose the TR20
Rear-Axle Control
Built to support the front brake package, hold bias, and keep rear contribution predictable through a full session.
Thermal Repeatability
Ø330 mm × 25 mm two-piece vented rotor with directional vane pattern keeps stop-to-stop temperatures predictable through a session.
Race Pad Window
Open piston design without dust boots supports race pad operating ranges up to 600 °C standard or 750 °C with the Option B compound.
Serviceability
Two-piece forged construction, replaceable rotor rings, and standard race-pad shapes shorten paddock turnaround between sessions.
Vehicle-Specific Engineering
Rear bias, rotor package, bracket geometry, brake line routing, and wheel clearance are confirmed before production.
Technical Specifications & Kit Options
| Brake Caliper | ||
|---|---|---|
| Series | Racing Series — Circuit | |
| Model / Application | TR20 | |
| Axle Position | Rear | |
| Piston Count | 2-piston | |
| Piston Type | Racing pistons without dust boots | |
| Piston Diameter | 44.4 mm × 2 | |
| Caliper Dimensions | 182.3 mm × 148 mm × 71.6 mm | |
| Total Piston Area | 30.95 cm² per caliper, all pistons combined | |
| Manufacturing Process | Two-piece forged aluminum body | |
| Net Weight | 1.73 kg per caliper, without pads | |
| Surface Finish | Nickel-plated | |
| Custom Color | Not available on this caliper line | |
| Recommended Wheel Size | 17 in or larger | |
| Recommended Rotor Size | Ø330 mm × 25 mm | |
| Brake Rotor Options | ||
| Rotor Option | Standard | Option B |
| Rotor Material | Heat-treated high-carbon cast iron | Racing-grade heat-treated high-carbon cast iron |
| Axle Position | Rear | Rear |
| Rotor Dimensions | Ø330 mm × 25 mm | Ø330 mm × 25 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, depending on rotor size and vehicle application | Fixed or floating, depending on rotor size and vehicle 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 |
| Recommended Use | Steel rotor build for circuit, drift, rally, and endurance rear-axle control | Racing steel rotor build for higher peak energy events and heavier rear brake use |
| Brake Pad Options | ||
| Pad Option | Standard | Option B |
| 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 temperature, line pressure, and rotor condition | μ ≈ 0.45; varies with temperature, line pressure, and rotor condition |
| Recommended Use | Track, drift, rally, and rear brake contribution in balanced motorsport packages | Endurance, downhill rally stages, heavy drift entries, and higher peak energy events |
| Lines, Brackets & Service | ||
| Brake Line Construction | Three-layer reinforced construction | |
| Brake Line Material | PTFE inner liner / SUS304 stainless-steel braid / PVC protective outer sheath | |
| Caliper Mounting | Radial mount with vehicle-specific caliper brackets | |
| Caliper Brackets | Vehicle-specific radial caliper brackets confirmed during the build workflow | |
| Rotor Hats | Application-specific alloy rotor hats matched to rear hub geometry and rotor offset | |
| Brake Line Fittings | Vehicle-specific; caliper-side and chassis-side fittings vary by application | |
| Wheel Clearance | 17 in wheels or larger; spoke profile is verified before production for race wheel sets | |
| Rotor Service | Two-piece rotor design allows friction ring replacement while retaining the alloy hat when serviceable | |
| Bedding-In Procedure | Required before pushing the system to race pace | |
Option B is intended for higher peak energy events — endurance, downhill rally stages, or heavy drift entries — where the standard pad would push past its window. Caliper finish is nickel-plated; color customization is not available on this caliper line.
Package List
Calipers ×2
2 × TR20 rear two-piece forged 2-piston calipers with nickel-plated finish.
Brake Pads
Brake pads for both rear calipers, selected from Standard 0–600 °C or Option B 0–750 °C compound.
Brake Rotors ×2
2 × two-piece internally vented rear rotors, Ø330 mm × 25 mm, left/right specific.
Caliper Brackets ×2
Vehicle-specific radial caliper brackets for correct rear caliper position and 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 stainless-steel braid, and PVC protective outer sheath.
The Bespoke Engineering Process
Every TR20 rear racing system is engineered around the vehicle’s rear knuckle, hub location, rotor hat offset, wheel barrel, spoke clearance, brake line routing, front BBK pairing, rear bias target, axle role, and intended motorsport use. The goal is not a generic universal fit; the goal is a rear brake package that supports the front axle, holds bias, and gives the driver repeatable pedal behavior across a full session.
1. Technical Consultation
We review the vehicle, rear suspension and knuckle setup, axle role, current front brake setup, target bias, competition use, wheel package, tire compound, and whether the car uses OEM or custom rear uprights.
2. Data Submission
For OEM knuckles, provide vehicle details, current front brake setup, wheel size, wheel specs, and intended use. For custom rear uprights, provide CAD files, technical drawings, hub-face data, rotor mounting dimensions, or accurate bracket mounting-point measurements.
3. Engineering Review & Approval
TTSPORT confirms rear bias target, rotor option, pad compound, vehicle-specific caliper bracket geometry, rotor hat offset, brake line routing, and wheel clearance before the build is released.
If you are unsure whether your wheel, rear knuckle, front BBK pairing, rotor offset, brake line routing, or rear bias target is suitable, Contact us before ordering so the engineering team can review the build details.
Installation & Break-In
- Confirm vehicle, axle role, and front BBK pairing for the target rear bias.
- Verify 17 in or larger wheel fitment and spoke clearance against the TR20 caliper envelope.
- Lock bracket geometry, rotor offset, and brake line routing before production.
- TR20 rear kits ship with vehicle-specific caliper brackets, rotor hats, and braided rear lines.
- Use Standard pad and rotor specification for balanced rear contribution in circuit, drift, rally, and endurance packages.
- Use Option B for higher peak energy events where the rear brake package sees sustained heat.
- A proper bed-in procedure is required to seat the pad transfer layer before pushing the system to race pace.
Frequently Asked Questions
Is the TR20 a front or rear caliper?
The TR20 is a dedicated rear caliper — a 2-piston, 30.95 cm² platform sized to balance a larger front BBK without overbraking the rear axle.
What rotor size does it run?
Ø330 mm × 25 mm, two-piece, internally vented, directional left/right-specific. Available with standard high-carbon steel or racing-grade heat-treated steel.
What is the difference between the standard and Option B pad?
The standard pad runs 0–600 °C with μ ≈ 0.38. Option B extends the window to 0–750 °C at μ ≈ 0.45 for endurance, rally, and heavy drift work.
Will it clear my wheels?
17-inch wheels or larger are required. Spoke profile is verified against the caliper envelope during the build workflow before production starts.
Can I change the caliper color?
No. The TR20 ships nickel-plated and color customization is not offered on this race line.
Is bedding-in required?
Yes. A proper bed-in procedure is required to seat the pad transfer layer before pushing the system to race pace.
Spec Your TR20 Rear Kit
Send your vehicle, current front brake setup, wheel size, and intended use. Our engineering team will confirm rotor option, pad compound, bracket package, rotor hat offset, brake line routing, and wheel clearance before the build is released.
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
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★★★★★ 5
Nice buy
Color: 5885 blue dial, Color: 5885 blue dial
Very classy nice fit feels real good great quality
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Reviewed in the United States on February 24, 2026
★★★★★ 5
Realistic
Color: rose steel black dial
Like the style & not trying to be someone I'm not.
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Reviewed in the United States on April 9, 2026
★★★★★ 5
Great Value
Color: 5885 steel black dial
Outstanding quality and value.
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Reviewed in the United States on March 10, 2026
★★★★★ 4
Very stylish but not the best quality
Color: Silvery Gold green dial, Color: Silvery Gold green dial
You are getting what you pay for: the color of the dial is amazing. It looks so stylish and can really accessorize an outfit. The packaging of the watch was very nice and it came with tools to adjust the size of the watch. However the links color is not the best color and quality. The watch feels light but in a cheaper feel. I’ve ordered other watches from Amazon that in my opinion were nicer and felt and looked high end. I got this watch on sale for Black Friday but I’m not sure if I would pay full price for it.
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Reviewed in the United States on January 14, 2026
★★★★★ 5
Bracelet opens too easy for any time activity
Color: Silvery green dial 5885
Watch face too small more for women tastes
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Reviewed in the United States on June 6, 2026