- In stock, ready to ship
- Free shipping on all orders $59+
The e*thriteen Helix Race 12-speed cassette is engineered to deliver precision shifting performance with an industry-leading gear range. The proprietary 9-tooth smallest cog enables the use of a smaller chainring for improved clearance, lighter system weight, and a lower bail-out gear ratio without high gear compromise.
- Seamless cross-compatibility with Shimano, SRAM, and TRP 12-speed drivetrains
- The patented 2-Part design provides strength, stiffness, lightweight, and ease of service
- Aluminum and steel clusters can be replaced separately to reduce service cost
- 9-tooth high gear allows the use of smaller chainrings for clearance and weight savings
- Fits XD™ and XDR™ Drivers Only (Hope XD drivers are undersized at the clamp location and require a Cassette Shim Kit -Sold Separately)
- Tested extensively for analog and e-bike use
Helix Race Cassette 9-45t
| Range: | 9-45t, 500% |
| Cassette Cogs: | 9-11-13-15-17-19-22-25-28-32-38-45 |
| Rear Speeds | 12-Speed |
| Weight: | 319 grams |
| Freehub: | SRAM XD and XDR driver |
Helix Race Cassette 9-50t
| Range: | 9-50t, 556% |
| Cassette Cogs: | 9, 11, 13, 15, 17, 20, 23, 27, 31, 36, 42, 50 |
| Rear Speeds | 12-Speed |
| Weight: | 384 grams |
| Freehub: | SRAM XD and XDR driver |
Helix Race Cassette 9-52t
| Range: | 9-52t, 578% |
| Cassette Cogs: | 9, 11, 13, 15, 17, 20, 23, 27, 31, 36, 43, 52 |
| Rear Speeds | 12-Speed |
| Weight: | 404 grams |
| Freehub: | SRAM XD and XDR driver |
Helix Race Cassette 13-52t
| Range: | 13-52t, 400% |
| Cassette Cogs: | 13, 15, 17, 19, 22, 25, 28, 32, 36, 40, 45, 52 |
| Rear Speeds | 12-Speed |
| Weight: | 467 grams |
| Freehub: | SRAM XD and XDR driver |
Please reach out to us with any questions you may have on anything we sell. We want to make sure you get the right items the first time. Our lifelong riders at Thunder Mountain Bikes are knowledgeable and would love to talk to you!
Shipping
We currently offer both economy and expedited shipping options though FedEX and USPS.
Orders totaling over $59 are eligible to ship for free via an economy ground option of our choice.
Most bikes ship free within the continental US. Bike shipping to AK, HI, or PR is $250.
If you're in need of something super-quick, please contact us directly. We may be able to overnight your order with an additional fee and depending on your location.
RETURNS
Should there be an issue with the item you bought, or you no longer need your purchase, we will be happy to set up a return.
Component & Gear Returns
Returns may be requested within sixty (60) days of the delivery date. All returned items must be received in new, unused, and uninstalled condition, with the original tags and labels attached and in the original packaging. We cannot accept returns on any items installed or show wear of any kind.
Bike Returns
Returns or exchange requests for bikes must be requested by emailing us at sedona@thundermountainbikes.com within fifteen (15) days from the date of delivery. Bikes must be in un-ridden condition. Custom-built bikes may not be returned. Returned bikes have a $200 restocking fee and the customer pays for return shipping.
Return Shipping
Customers may choose to use our provided flat-rate return shipping label at $9, or choose a carrier of their choice to handle their product return.
The $9 flat rate label will be deducted from the refund issued for the return. You can either print this label after requesting a return from the Order History in your Account profile, or you can request that we email you the label.
For all other return shipping methods, please email us at sedona@thundermountainbikes.com after submitting your return request so that we can confirm the shipping information you should use to return your item(s).
REFUNDS
We will process your return after we receive your returned item(s) and inspect the condition. Please allow at least seven (7) days from the receipt of your item to process your refund. We will notify you by email when your return has been processed.
EXCEPTIONS
If you receive defective or damaged products or if we sent you the wrong products, please contact us using the phone number or email below.
RETURN PROCESS
To request a return, please log in to your customer account by clicking the 
Profile icon in the top right of any page or visit account.thundermountainbikes.com.
1. In the Email field, enter your email address and click Continue.
2. In your email account, open the email sent from our store and copy the six-digit verification code included in the email.
3. Go back to the online store and enter a six-digit verification code to log in.
4. Find and click on the order that you want to submit a return for.
5. If your order has more than one item, select only the items you want to return.
6. Select a return reason and add a note for the store if needed.
7. Click Request Return.
Once your return request is approved, you will receive an email with shipping instructions and a return shipping label.
QUESTIONS ABOUT RETURNS?
If you have any questions concerning our return policy, please contact us at:
