About The Product
- 6/7-speed MTB rear derailleur
- Engineered polymer and steel construction
- Direct mount with optional hanger included
- SHIMANO Equivalent RD-TY21 / RD-A070
Upgrade Your Mountain Biking Performance with the Sunrace RD-M37 Rear Derailleur - 7-Speed, Mid-Engine Polymer & Steel Construction
Maximize your bike's shifting efficiency and durability with the Sunrace RD-M37 Rear Derailleur, a reliable choice for serious mountain bikers and cycling enthusiasts. Engineered for durability and performance, this 7-speed derailleur is designed to handle rugged trails and demanding terrain.
Premium Materials and Engineering
Constructed from a high-quality blend of engineered polymer and steel, the Sunrace RD-M37 offers exceptional strength and lightweight performance. The polymer components reduce weight without sacrificing durability, while the steel parts ensure longevity and resistance to impact. At just 265 grams, it delivers a balanced combination of sturdy build and nimble handling, ideal for mountain biking adventures.
Optimized Components & Technology
Featuring a 2-to-1 ratio and a maximum sprocket size of 30 teeth, this derailleur provides smooth and precise shifting across all 6/7 gears. Its mid-cage design ensures compatibility with a wide range of MTB cranksets, while the direct mount system offers secure attachment and easy installation. The included removable hanger enhances versatility and simplifies maintenance, making it an excellent upgrade for your existing drivetrain.
Performance & Use Case
Designed to stand up to the rigors of mountain biking, the Sunrace RD-M37 excels in trail, cross-country, and aggressive riding environments. Its robust construction and reliable gear indexing provide consistent performance over rough terrain, helping you maintain control and confidence on every ride.
Innovative Features & Compatibility
This derailleur is comparable to Shimano's RD-TY21 and RD-A070 models, offering a cost-effective alternative without compromising quality. Its innovative polymer and steel construction not only ensure durability under harsh conditions but also reduce overall bike weight, enhancing overall ride efficiency.
Key Specifications:
- Gear Wrap: 37
- Mount: Mid
- Gear Ratio: 2to1
- Max Sprocket Size: 30 teeth
- Weight: 265g
Perfect for mountain bikers seeking durable, lightweight, and reliable drivetrain components. Elevate your bike's shifting performance with the Sunrace RD-M37 Rear Derailleur - engineered for adventure, built to last.
- High-performance 7-speed MTB rear derailleur engineered with durable polymer and steel construction for enhanced strength, longevity, and reliable shifting.
- Designed with a direct mount system and removable hanger for easy installation, maintenance, and compatibility with a wide range of mountain bikes.
- Built with advanced gear ratios (2:1) and a wide 30-tooth max sprocket capacity, delivering precise, smooth, and confident gear transitions on rugged terrain.
- Lightweight at only 265 grams, offering an optimal balance between durability and performance for aggressive trail riding and mountain biking exigeances.
- Compatible with Shimano-driven drivetrains (RD-TY21 / RD-A070 equivalents), ensuring seamless integration with your existing bike components for a cohesive shifting experience.
| Specification | Value |
|---|---|
| Manufacturer | SUNRACE |
| Manufacturer Part No. | RDM37.SDB0.0S4.BX |
| Universal Product Code | 4710944235111 |
| Invoice Description | DER SUNRACE RDM37 GS 7s DIRECT BKw/REMOVABLE HANGER |
| Shipping Weight | 0.80 lbs. |
| Package Dimensions | 7 x 4.1 x 3.65 |
| HTS Number | 8714.99.5000 |
| Country of Origin | TAIWAN |
| Speed | 7sp |
| Max | 30 |
| Wrap | 37 |
| Cage/Mount | Mid |
| Ratio | 2to1 |
| Color | BLK |
| Wgt | 265g |
| Type | Mechanical |
- Supplier:
- JBI
Bike Junkies offers no‑hassle returns and exchanges within 60 days of delivery. We want every customer to feel confident when shopping with us, and our return process is designed to be simple, fair, and fast.
Return Eligibility
To qualify for a return or exchange, the following conditions must be met:
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The item must be in new, unused, and uninstalled condition.
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All original packaging, tags, hardware, and accessories must be included and intact.
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Items showing wear, installation marks, damage, or improper use cannot be accepted.
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An order number is required.
Once your return is received at our warehouse, a refund will be issued within 5 days after inspection.
Refunds
Refunds are issued to the original form of payment once the returned item has been received and approved. If we are unable to refund to the original payment method, the refund will be issued as store credit.
Depending on your bank or credit card provider, it may take an additional 2–3 business days for the refund to appear in your account.
Exchanges
To make an exchange, simply complete the return process and then place a new order for the item you want instead. This ensures the replacement item is reserved and ships quickly.
How to Start a Return
To request a Return Authorization (RA#), contact us at support@bikejunkies.com. Please include your order number and the item you wish to return.
Once approved:
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You will receive a Return Authorization email with instructions.
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Print the prepaid label provided by us. ($9.99 will be deducted from your refund)
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Ship the item back within 7 days of the RA being issued as RA #'s are only valid for 7 days.
Please do not tape anything to the original product packaging. Place the item inside a proper shipping box. Using the manufacturer’s box as the shipping container will result in damage and the return may be rejected.
Be sure to keep your return tracking number. Powersport Junkies is not responsible for lost return shipments. You will receive a confirmation email once your return has been processed and refunded.
Defective, Incorrect, or Damaged Items
If you receive a defective, damaged, or incorrectly shipped item, contact us immediately. We will cover the return shipping cost and ensure the issue is resolved quickly.
Non‑Returnable Items
Certain items cannot be returned, including:
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Electronics with opened packaging or broken manufacturer seals
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Any part that has been installed or shows installation attempts
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Tools or chemicals that have been opened or unsealed
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Open‑box items with destroyed or missing packaging
Our Info
-
Storefront name: Bike Junkies
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Address: 940 Calle Amanecer, Suite N
San Clemente, CA 92673 -
Phone: 800-605-2152
-
Support email: support@bikejunkies.com
- Support hours + timezone:
Monday-Friday: 9:00 AM-5:00 PM PST
Saturday: 9:00 AM-3:00 PM PST
Sunday: Closed
This Shipping Policy explains how orders are processed, handled, and delivered by Bike Junkies, including delivery timelines, shipping coverage, and special conditions for military addresses. It is designed to give customers a clear understanding of what to expect when placing an order.
Bike Junkies is proud to be an authorized dealer of the brands we currently offer. When you purchase from us, you are guaranteed to receive genuine, brand-new products backed by the full manufacturer warranty. We work directly with the manufacturers to ensure you receive the highest quality service and support.
Order Processing and Handling
Orders are processed quickly to ensure fast delivery. Our standard handling time is 0–1 business days. Order cutoff time is 12 PM PST Monday-Friday and orders placed after that will be shipped shipped next business day.
Transit Times
Once shipped, orders typically arrive within 2–3 business days. Transit times may vary slightly depending on the destination, weather conditions, or carrier-related delays. Delivery estimates apply only after the order has left our facility.
Delivery Schedule
Standard delivery occurs Monday through Friday. Saturday delivery may be available.
Shipping Coverage
Bike Junkies offers free shipping to the lower 48 states of the United States. We do not ship to the following locations:
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Alaska
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Hawaii
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Puerto Rico
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Any international destination outside the United States
Orders placed with shipping addresses in restricted locations will be canceled and refunded.
Military Shipping (APO/FPO)
Bike Junkies ships to APO/FPO military addresses using USPS only.
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We cannot ship hazardous materials or oversized items to military addresses due to carrier and military mail restrictions.
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Transit times to APO/FPO locations may vary significantly depending on military mail processing.
Address Accuracy and Delivery Issues
Customers are responsible for ensuring that all shipping information provided at checkout is accurate and complete. Bike Junkies is not responsible for delays, lost packages, or delivery failures caused by incorrect or incomplete addresses. If a package is returned due to an address error, additional shipping charges may apply to resend the order.
Lost, Delayed, or Damaged Shipments
If a shipment is delayed, lost, or arrives damaged, customers should contact us promptly so we can assist with initiating a claim or resolving the issue with the carrier. While we support the process, final decisions regarding claims are made by the carrier.
Tracking Information
A tracking number is provided via email once the shipping label has been created. Tracking updates may take up to 24 hours to appear after the label is generated.
Shipping Restrictions
Certain items may be subject to shipping restrictions due to size, weight, or hazardous material regulations. If an order cannot be shipped due to such restrictions, we will notify the customer to arrange an alternative solution.
Our Info
-
Storefront name: Bike Junkies
-
Address: 940 Calle Amanecer, Suite N
San Clemente, CA 92673 -
Phone: 800-605-2152
-
Support email: support@bikejunkies.com
- Support hours + timezone:
Monday-Friday: 9:00 AM-5:00 PM PST
Saturday: 9:00 AM-3:00 PM PST
Sunday: Closed
For warranty issues please contact us at support@bikejunkies.com. Each Brand is different and we can provide instruction to complete warranty issues.
Bike Junkies is proud to be an authorized dealer of the brands we currently offer. When you purchase from us, you are guaranteed to receive genuine, brand-new products backed by the full manufacturer warranty. We work directly with the manufacturers to ensure you receive the highest quality service and support.
Our Info
-
Storefront name: Bike Junkies
-
Address: 940 Calle Amanecer, Suite N
San Clemente, CA 92673 -
Phone: 800-605-2152
-
Support email: support@bikejunkies.com
- Support hours + timezone:
Monday-Friday: 9:00 AM-5:00 PM PST
Saturday: 9:00 AM-3:00 PM PST
Sunday: Closed
