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Girodisc
D1-211 Girodisc Front Rotor Ring Replacements
$800.00
REPLACEMENT ROTOR RINGS ONLY. INCLUDES NEW INSTALLATION HARDWARE. DOES NOT INCLUDE ALUMINUM HATS.
Thunderhill is an authorized dealer for Girodisc products. As one of the largest stocking dealers in the country, we ship most Girodisc products the same or next business day to ensure we meet your delivery deadline.
These Girodisc replacement rotor rings are direct replacements for the iron discs on your Girodisc two-piece rotors, and no modifications are necessary. New cap screws and washers are included with these replacement rotors. We do not recommend re-using the old hardware.
The replacement rotor rings and hat mount together through a floating mount system which utilizes 8-10 high strength alloy steel drive pins manufactured by Girodisc in the USA to their own specifications and are cadmium plated for corrosion resistance. The alloy drive pins transfer the load from the brake action while maintaining the axial and radial float between the disc rotor and hat. The pins are secured by grade 12 cap screws with hardened washers and mounted with anti-noise spring washers to allow for heat expansion while eliminating the rattle and noise associated with floating rotors.
The two-piece Girodisc design allows for rotor ring-only replacement to minimize replacement costs and deliver outstanding performance and cooling.
Sold/priced per pair.
Girodisc
D1-172 Girodisc Front Rotor Ring Replacements
$800.00
REPLACEMENT ROTOR RINGS ONLY. INCLUDES NEW INSTALLATION HARDWARE. DOES NOT INCLUDE ALUMINUM HATS.
Thunderhill is an authorized dealer for Girodisc products. As one of the largest stocking dealers in the country, we ship most Girodisc products the same or next business day to ensure we meet your delivery deadline.
These Girodisc replacement rotor rings are direct replacements for the iron discs on your Girodisc two-piece rotors, and no modifications are necessary. New cap screws and washers are included with these replacement rotors. We do not recommend re-using the old hardware.
The replacement rotor rings and hat mount together through a floating mount system which utilizes 8-10 high strength alloy steel drive pins manufactured by Girodisc in the USA to their own specifications and are cadmium plated for corrosion resistance. The alloy drive pins transfer the load from the brake action while maintaining the axial and radial float between the disc rotor and hat. The pins are secured by grade 12 cap screws with hardened washers and mounted with anti-noise spring washers to allow for heat expansion while eliminating the rattle and noise associated with floating rotors.
The two-piece Girodisc design allows for rotor ring-only replacement to minimize replacement costs and deliver outstanding performance and cooling.
Sold/priced per pair.
Girodisc
D2-172 Girodisc Rear Rotor Ring Replacements
$800.00
REPLACEMENT ROTOR RINGS ONLY. INCLUDES NEW INSTALLATION HARDWARE. DOES NOT INCLUDE ALUMINUM HATS.
Thunderhill is an authorized dealer for Girodisc products. As one of the largest stocking dealers in the country, we ship most Girodisc products the same or next business day to ensure we meet your delivery deadline.
These Girodisc replacement rotor rings are direct replacements for the iron discs on your Girodisc two-piece rotors, and no modifications are necessary. New cap screws and washers are included with these replacement rotors. We do not recommend re-using the old hardware.
The replacement rotor rings and hat mount together through a floating mount system which utilizes 8-10 high strength alloy steel drive pins manufactured by Girodisc in the USA to their own specifications and are cadmium plated for corrosion resistance. The alloy drive pins transfer the load from the brake action while maintaining the axial and radial float between the disc rotor and hat. The pins are secured by grade 12 cap screws with hardened washers and mounted with anti-noise spring washers to allow for heat expansion while eliminating the rattle and noise associated with floating rotors.
The two-piece Girodisc design allows for rotor ring-only replacement to minimize replacement costs and deliver outstanding performance and cooling.
Sold/priced per pair.
Girodisc
D1-067 Girodisc Front Rotor Ring Replacements
$800.00
REPLACEMENT ROTOR RINGS ONLY. INCLUDES NEW INSTALLATION HARDWARE. DOES NOT INCLUDE ALUMINUM HATS.
Thunderhill is an authorized dealer for Girodisc products. As one of the largest stocking dealers in the country, we ship most Girodisc products the same or next business day to ensure we meet your delivery deadline.
These Girodisc replacement rotor rings are direct replacements for the iron discs on your Girodisc two-piece rotors, and no modifications are necessary. New cap screws and washers are included with these replacement rotors. We do not recommend re-using the old hardware.
The replacement rotor rings and hat mount together through a floating mount system which utilizes 8-10 high strength alloy steel drive pins manufactured by Girodisc in the USA to their own specifications and are cadmium plated for corrosion resistance. The alloy drive pins transfer the load from the brake action while maintaining the axial and radial float between the disc rotor and hat. The pins are secured by grade 12 cap screws with hardened washers and mounted with anti-noise spring washers to allow for heat expansion while eliminating the rattle and noise associated with floating rotors.
The two-piece Girodisc design allows for rotor ring-only replacement to minimize replacement costs and deliver outstanding performance and cooling.
Sold/priced per pair.
Girodisc
D1-249 Girodisc Front Rotor Rings (380mm)
$800.00
REPLACEMENT ROTOR RINGS ONLY. INCLUDES NEW INSTALLATION HARDWARE. DOES NOT INCLUDE ALUMINUM HATS.
Thunderhill is an authorized dealer for Girodisc products. As one of the largest stocking dealers in the country, we ship most Girodisc products the same or next business day to ensure we meet your delivery deadline.
These 380mm Girodisc replacement rotor rings are direct replacements for the iron discs on your Girodisc two-piece rotors, and no modifications are necessary. New cap screws and washers are included with these replacement rotors. We do not recommend re-using the old hardware.
These rings will not work with factory center hats. They are designed to work with Girodisc hats only.
The replacement rotor rings and hat mount together through a floating mount system which utilizes 8-10 high strength alloy steel drive pins manufactured by Girodisc in the USA to their own specifications and are cadmium plated for corrosion resistance. The alloy drive pins transfer the load from the brake action while maintaining the axial and radial float between the disc rotor and hat. The pins are secured by grade 12 cap screws with hardened washers and mounted with anti-noise spring washers to allow for heat expansion while eliminating the rattle and noise associated with floating rotors.
The two-piece Girodisc design allows for rotor ring-only replacement to minimize replacement costs and deliver outstanding performance and cooling.
Sold/priced per pair.
Girodisc
D1-232 Girodisc Front Rotor Rings (390mm)
$800.00
REPLACEMENT ROTOR RINGS ONLY. INCLUDES NEW INSTALLATION HARDWARE. DOES NOT INCLUDE ALUMINUM HATS.
Thunderhill is an authorized dealer for Girodisc products. As one of the largest stocking dealers in the country, we ship most Girodisc products the same or next business day to ensure we meet your delivery deadline.
These 390mm Girodisc replacement rotor rings are direct replacements for the iron discs on your Girodisc two-piece rotors, and no modifications are necessary. New cap screws and washers are included with these replacement rotors. We do not recommend re-using the old hardware.
These rings will not work with factory center hats. They are designed to work with Girodisc hats only.
The replacement rotor rings and hat mount together through a floating mount system which utilizes 8-10 high strength alloy steel drive pins manufactured by Girodisc in the USA to their own specifications and are cadmium plated for corrosion resistance. The alloy drive pins transfer the load from the brake action while maintaining the axial and radial float between the disc rotor and hat. The pins are secured by grade 12 cap screws with hardened washers and mounted with anti-noise spring washers to allow for heat expansion while eliminating the rattle and noise associated with floating rotors.
The two-piece Girodisc design allows for rotor ring-only replacement to minimize replacement costs and deliver outstanding performance and cooling.
Sold/priced per pair.
Girodisc
D2-232 Girodisc Rear Rotor Rings
$800.00
REPLACEMENT ROTOR RINGS ONLY. INCLUDES NEW INSTALLATION HARDWARE. DOES NOT INCLUDE ALUMINUM HATS.
Thunderhill is an authorized dealer for Girodisc products. As one of the largest stocking dealers in the country, we ship most Girodisc products the same or next business day to ensure we meet your delivery deadline.
These Girodisc replacement rotor rings for the Nissan R35 GT-R are Girodisc's updated variant. If you're not sure these are correct for your Girodisc rotors, please contact us.
They the are direct replacements for the iron discs on your Girodisc two-piece rotors, and no modifications are necessary. New cap screws and washers are included with these replacement rotors. We do not recommend re-using the old hardware.
These rings will not work with factory center hats. They are designed to work with Girodisc hats only.
The replacement rotor rings and hat mount together through a floating mount system which utilizes 8-10 high strength alloy steel drive pins manufactured by Girodisc in the USA to their own specifications and are cadmium plated for corrosion resistance. The alloy drive pins transfer the load from the brake action while maintaining the axial and radial float between the disc rotor and hat. The pins are secured by grade 12 cap screws with hardened washers and mounted with anti-noise spring washers to allow for heat expansion while eliminating the rattle and noise associated with floating rotors.
The two-piece Girodisc design allows for rotor ring-only replacement to minimize replacement costs and deliver outstanding performance and cooling.
Sold/priced per pair.
Girodisc
D1-186 Girodisc Front Rotor Ring Replacements
$800.00
Girodisc D1-186 Replacement Rotor Rings (Discs)
Girodisc replacement rotor rings are direct replacements for the iron discs on your Girodisc A1-186 two-piece rotors, with no modifications necessary. New cap screws and washers are included with these replacement rotors. We do not recommend re-using the old hardware.
(This kit is contains two cast-iron discs and associated hardware. No aluminum center hat.)
The replacement rotor rings and hat mount together through a floating mount system which utilizes 8-10 high strength alloy steel drive pins manufactured by Girodisc in the USA and are cadmium plated for corrosion resistance. The alloy drive pins transfer the load from braking while maintaining the axial and radial float between the disc rotor and hat. The pins are secured by grade 12 cap screws with hardened washers and mounted with anti-noise spring washers to allow for heat expansion while eliminating the rattle and noise associated with floating rotors.
Rotor ring-only replacement helps to minimize costs and deliver outstanding performance.
Sold/priced per pair.
Girodisc
D2-186 Girodisc Rear Rotor Ring Replacements
$800.00
Girodisc D2-186 Replacement Rotor Rings (Discs)
Girodisc replacement rotor rings are direct replacements for the iron discs on your Girodisc A2-186 two-piece rear rotors, with no modifications necessary. New cap screws and washers are included with these replacement rotors. We do not recommend re-using the old hardware.
(This kit is contains two cast-iron discs and associated hardware. No aluminum center hat.)
The replacement rotor rings and hat mount together through a floating mount system which utilizes 8-10 high strength alloy steel drive pins manufactured by Girodisc in the USA and are cadmium plated for corrosion resistance. The alloy drive pins transfer the load from braking while maintaining the axial and radial float between the disc rotor and hat. The pins are secured by grade 12 cap screws with hardened washers and mounted with anti-noise spring washers to allow for heat expansion while eliminating the rattle and noise associated with floating rotors.
Rotor ring-only replacement helps to minimize costs and deliver outstanding performance.
Sold/priced per pair.
Girodisc
D1-203 Girodisc Front Replacement Rotor Rings (350mm)
from $800.00
Girodisc Rotor Rings (No Hats)
Need new rings for your Girodisc 350mm two-piece rotors? We've got them. Rings come complete with new hardware and full instructions for assembly to your existing Girodisc hats.
Price is for a pair of rings and hardware kits. Additional hardware kits are available separately.
Girodisc
D2-228 Girodisc Rear Rotor Ring Replacements (Super Trofeo)
$800.00
FITS: Lamborghini Huracan Super Trofeo ONLY
REPLACEMENT ROTOR DISCS ONLY, DOES NOT INCLUDE ALUMINUM HAT.
Thunderhill is an Authorized dealer for GiroDisc products and we are one of the largest stocking dealers in the country. We ship most products same or next business day to ensure we meet your delivery deadline.
The GiroDisc replacement rotor system is a direct rotor disc replacement for the OEM 2-piece hat and rotor and no modifications are necessary.
The rotor and hat mount together through a floating mount system which utilizes 8-10 high strength alloy steel drive pins manufactured by GiroDisc in the USA to our own specifications and are cadmium plated for corrosion resistance. The alloy drive pins transfer the load from the brake action while maintaining the axial and radial float between the disc rotor and hat. The pins are secured by grade 12 cap screws with hardened washers and mounted with anti-noise spring washers to allow for heat expansion while eliminating the rattle and noise associated with floating rotors.
The 2-piece GiroDisc design allows for rotor only replacement to minimize replacement costs and deliver outstanding performance and cooling.
Sold/Priced per pair.
HJC
HJC H10 Carbon Fiber Helmet SA2020
$799.99
HJC H10 Carbon Fiber SA2020 Auto Racing Helmet
The HJC H10 Carbon Fiber SA2020 helmet is ideal for use in all types of auto racing. From the dusty ovals of Tennessee to the starting line at Pomona, its comfortable fire-resistant, moisture-wicking Comfort-Carbon interior and Advanced Ventilation System keep you cool and comfortable. The HJC H10 Carbon is an affordable alternative to more expensive carbon fiber helmets without sacrificing fit, feel or safety.
HJC H10 Carbon Fiber SA2020 Auto Racing Helmet Details:
Snell SA2020 approved
Weight (Large): 3.2 lbs (1.45 kg)
Carbon fiber composite weave shell is extremely light weight
Superior fit and comfort using advanced CAD technology
ACS (Advanced Channeling System) provides front-to-back airflow flushing heat and humidity up and out
Optional shields available: Amber, Dark Smoke, Dark Blue, Black Chrome
Optional clear spoiler is available
Polycarbonate anti-fog shield with tear-off posts
Pre-installed M6 terminals for head and neck restraints
Improved front ventilation
Double D-ring retention system
Additional shields for the HJC H10 Carbon Fiber helmet are available here.
HJC H10 Carbon Fiber Sizing Chart:
SIZE
CENTIMETERS
HAT SIZE
INCHES
XS
54-55
6 3/4 – 6 7/8
21 1/4 – 21 5/8
S5
56-57
7 – 7 1/8
M
58-59
7 1/4 – 7 3/8
22 7/8 – 23 1/4
L
60-61
7 1/2 – 7 5/8
23 5/8 – 24
XL
62-63
7 3/4 – 7 7/8
24 3/8 – 24 3/4
XXL
64-65
8 – 8 1/8
25 1/4 – 25 5/8
Bell
Bell Racing MAG-10 Pro Helmet SA2025
$799.95
Bell Racing MAG-10 Pro Helmet FIA8859-2024 / SA2025
The Bell MAG-10 is a professional-grade open-face helmet designed for drivers who want maximum comfort, communication flexibility, and uncompromising safety. With dual certification to FIA8859-2024 and Snell SA2025, this helmet delivers advanced protection along with premium fit and ventilation for long stints behind the wheel.
Pro-level comfort and performance in an open-face design
Dual certification
The MAG-10 meets both FIA8859-2024 and Snell SA2025 standards, ensuring it is approved for international competition and long-term use in sanctioned racing series.
Lightweight composite shell
Engineered with a strong yet lightweight composite shell, this helmet provides superior impact protection while minimizing weight to reduce fatigue in endurance driving.
Integrated visor and sun protection
The MAG-10 features a dark-tinted adjustable visor to protect against glare and improve visibility in bright conditions, making it ideal for open-cockpit racing and track use.
Communication-ready interior
Designed with professional drivers in mind, the helmet’s interior is compatible with radio communication systems, making it a perfect choice for endurance and rally teams.
BELL RACING MAG-10 PRO SA2025 HELMET SIZE CHART
BELL RACING MAG-10 PRO SA2025 HELMET FAQs:
What certifications does the MAG-10 carry? The MAG-10 is dual certified to FIA8859-2024 and Snell SA2025 standards, making it legal for most international and domestic racing series.
Is this helmet communication-ready? Yes, the MAG-10 is designed with integration points for radio and intercom systems, making it a favorite for endurance and rally applications.
Does the MAG-10 provide sun protection? Yes, it comes with an adjustable tinted visor to reduce glare and maintain clear vision in bright conditions.
Who is the MAG-10 designed for? This helmet is perfect for professional and amateur racers in open-cockpit series, rally, endurance, and track-day events where communication and comfort are critical.
The Bell MAG-10 combines professional-level safety with the comfort and versatility of an open-face design, making it the ultimate helmet for serious racers who demand performance and reliability.
Bell
Bell GTX.3 Helmet SA2020
$799.95
Bell Racing Helmets GTX.3 SA2020 Composite
With its refined, aerodynamic design and lightweight carbon composite shell, the Bell Racing Helmets GTX.3 Composite SA2020 helmet provides the best performance and pro features for open wheel, open compartment, karting, formula and dirt track racers. This Bell GTX.3 Composite SA2020 has an integrated shield and dual screen anti-fog (DSAF) visor with rear-facing vents which are ideal for these forms of racing, allowing for air exchange and unobstructed vision without worrying about dust and dirt.
Bell Racing GTX.3 Auto Racing Helmet Features
Snell SA2020 and FIA 8859-2015 homologation
Includes clear SE03 3mm DSAF shield (SV SE03/05 pivot system) with DSAF anti-fog insert
Sleek aero styling with integrated wing
Front chin bar Gurney ("duckbill") improves high-speed aerodynamic performance
Venturi airflow system lets fresh air in, hollow synthetic rubber gasket seal keeps dirt, water and dust out
High-strength, lightweight carbon-composite construction using new high-pressure molding system
Multi-piece, multi-density high-impact custom bead absorbing liner for low- and high-velocity impact protection
Ultra-plush grey Comfort-Max FR® interior fabric wicks away moisture
Install integrated drinking tube and radio microphone systems with the integrated face piece channels
Multi-density foam interior and contoured cheek pads offer a professional fit
Standard-sized eye port
M6 terminal hardware and hex wrench for Head and Neck Restraint devices
Additional visor shields for the Bell Racing GTX.3 available here.
Bell
Bell GT6 Pro Helmet SA2020
$799.95
Bell Racing Helmets GT6 Pro Composite SA2020
The Bell Racing GT6 Pro auto racing helmet features the same modern and aggressive design as HP6, developed for racers in closed-car environments and featuring a wide eyeport for extended vision with a lightweight Premium carbon glass shell. Its ventilation slots can be connected to various types of air intakes for external cooling systems. It can be fitted with optional ear cups providing optimal noise insulation, with fully integrated radio communication kit and hydration systems (available separately).
Bell GT6 Pro Auto Racing Helmet Features
Lightweight premium carbon/fiberglass composite shell
FIA 8859-2015 and Snell SA2020 homologated
Wide eye port for excellent vision in closed-cockpit cars
Advanced multi-density, multi-piece liner maximizes energy absorption and impact performance
Integrated channels in face piece offer multiple options to install drink tube and radio systems
Extraction vents maximize cooling and air circulation
Factory-installed HANS anchors
Optional top forced-air intake can be installed on the left or right top side vents for use with an external cooling system
Optional ear cups increase noise insulation
Interior: Dark Grey high-strength, high comfort FR fabric
Additional Bell Racing GT6 Pro Helmet Visors Are Available Here
Bell GT6 Pro Auto Racing Helmet Colors
The Bell GT6 Pro is availabile in your choice of Gloss White or Matte Black.
Bell GT6 Pro Auto Racing Helmet Sizes
Available in Sizes: 54cm (6-3/4) to 61cm+ (7-5/8)
What Comes in the Bell GT6 Pro Helmet Box?
Bell Racing GT6 Pro SA2020 composite auto helmet
Clear SE06 3mm DSAF shield (installed)
Drawstring Bell helmet pouch
Plastic tear-off posts (installed)
Hex wrench key
Bell
Bell KC7 CMR Champion Karting Helmet
$799.95
Bell Racing Helmets KC7-CMR Champion Karting Helmet
The Bell KC7-CMR is a karting specific helmet based on the same design as the top of the range HP7 carbon helmet, as used by some F1 drivers. Constructed using an ultra lightweight Carbon/Kevlar/Glass hand laminated shell with a 2mm double screen anti fog visor for perfect visibility in all conditions.
Ultra lightweight and strong carbon/kevlar/fibreglass composite shell
Striking Champion pink graphic design is sure to get you noticed
Anti fog visor provides excellent visibility
14 air intakes and extraction channels provide optimum airflow through the helmet
A range of spoilers and air intakes are available separately
The shell of the KC7-CMR is designed to provide the optimum visor location which improves aerodynamics and reduces noise. The powerful top and chin bar ventilation keeps the drivers head cool thanks to a total of no less than 14 air intakes and extraction channels.
A range of accessories including different visor options, spoilers and air intakes are available separately.
Helmet weights -
Sizes 54-56cm - 1185g ( /-3%)
Sizes 57-59cm - 1230g ( /-3%)
Snell-FIA CMR-2016 approved
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