🏷️ Not eligible for coupons or discounts.
Whether for prized race machines or the build of their dreams, the XG-1299 cassette is the ultimate, giving riders up to a 520-percent range thanks to the new 10-52 tooth span. Stronger racers are now free to choose larger chainrings for more top-end speed, without sacrificing climbing range. More time is spent higher up in the cassette where the athlete's power transfer is most efficient and wear is minimized. Featuring the industry’s strongest X-Dome™ architecture and proven XD™ driver body, it’s also backwards compatible to give riders even more Eagle™ upgrade options for their current bikes. With multiple Olympic, World Cup, and World Championship titles, it also matches up perfectly to XX1 Eagle AXS™ enabled componentry. The XG-1299 cassette utilizes the full depth of the new Eagle™ Color system. Available in Black to Gold to Rainbow and all-new Copper, the XG-1299 cassette completes the expression of the world's most accomplished and sought-after bikes.
Please reach out to us with any questions you may have about 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!
We currently offer both economy and expedited shipping options through FedEx and USPS.
Most orders totaling over $69 before tax are eligible to ship for free via an economy ground option of our choice.
Due to larger box sizes, handlebars, wheels, and other oversized items, an additional shipping fee will be applied.
Most bikes ship for only $200 within the continental US. Bike shipping to AK, HI, or PR is usually $350, but may incur additional fees depending on the exact delivery location.
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, depending on your location.
Should there be an issue with the item you bought, or if you no longer need your purchase, we will be happy to set up a return.
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 that have been installed or show wear of any kind.
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 incur a $200 restocking fee, and the customer is responsible for the return shipping costs.
Customers are responsible for return shipping fees and may choose the carrier of their choice to handle their product return. We no longer provide shipping labels directly.
For any return shipping questions, 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).
We will process your return after receiving your returned item(s) and inspecting their 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. All refunds will be returned to the original payment method. No store credit or other refund methods are available.
If you receive defective or damaged products or if we sent you the wrong item(s), please contact us using the phone number or email below.
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 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 a confirmation by email.
If you have any questions concerning our return policy, please contact us at:
I bought the SRAM XX1 Eagle groupset and later the Sram BB. Great products, fast shipping, awesome prices. The only thing that sucked was I signed up to get the 10% off promo code, but it didn’t work with anything I bought. Other than that no complaints.
I love the Eagle drivetrain components. They all fit well together and I like the color combo on this copper cassette with the XX1 black chain. This cassette is very lightweight and has been durable during rough rides.
Really nice upgrade from the eagle cassette that came with my new bike. I hope to get more that 600 miles from the xx1. Looks trick and shifts buttery smooth.
your 10% off hook n bait add is lame though.
Beautiful colored cassette
So nice and light compared to the standard cassettes.
The best of the best without the electric weight
Quick ship, easy to install, looks great. I'll have to visit the shop the next time I'm in Sedona!
Awesome delivery time , I’m in northeast Pa.
Plus I got an awesome sticker for the toolbox.
Hard to beat high end sram, but these folks at thunder mountain are giving them a run for the money
Thanks again
It looks even better in person. Thunder mountain always ships out quick with good packaging.
I'm redoing most of an older drivetrain, so it was great to see the wide selection of quality products, and the components arrived quickly. Thanks!
Product exactly as described, great cost and fast shipping!
This cassette is beautiful. I got a great price and it was shipped very quickly. Great customer service!
it never arrived
Love it ! I may be coming back for the XX1 Crankset!
XX1 Eagle XG-1299 Cassette
This dinner platter gets the job done. Whether grinding it out on the gnarly climbs or sending downhill. This cassette has no limits.
