Built for durability and value, the DEORE M6250 long-cage derailleur delivers smooth, wireless Di2 shifting and dependable performance across a wide gear range. Pair it with a standard 10-51T cassette for 510% range that’s ready for everything from backcountry climbs to aggressive descents. Designed with trail-tough features like Automatic Impact Recovery, a steel outer plate, and impact-deflecting wedge shape, it shrugs off rough terrain while maintaining crisp, precise shifts. The integrated battery is securely housed within the linkage for extra protection and easy removal when it’s time to recharge or sync devices.
Features:
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Robust Design: Steel plate, wide links, and a skid-plate-inspired shape ensure long-term durability.
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RD Protection Function: Auto-reset derailleur position after impacts with Automatic Impact Recovery.
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SHIMANO SHADOW ES: Sleek, quiet, and stable shifting from Shimano’s evolved chain-stabilizing tech.
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Precise Wireless Shifting: Fast, clean, and fully wireless performance with a 500% gear range.
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Protected Battery: Safely tucked inside the linkage, the battery stays secure yet removable for charging.
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Covered Pulleys/Cage: Shielded pulley teeth prevent trail debris from interfering with your ride.
Specs:
| Model: | Deore M6250 |
| Model ID: | RD-M6250-SGS |
| Max Tooth: | 51t |
| Drive Config: | 1x |
| Mount Interface: | Derailleur Hanger |
| Shift Technology: | Wireless |
| Communication Protocol: | Di2 |
| Weight: | TBD |
Compatibility
The Shimano Deore M2250 Di2 Rear Derailleur is 100% backward compatible with previous generation Shimano 12-speed chains and cassettes. Compatible models include: XTR M9100 and M9200, Deore XT M8100 and M8200, SLX M7100, and Deore M6100.
The XT M8250 Rear Derailleur is compatible with the following:
| Frame: | Modern framesets via a derailleur hanger, including the Universal Derailleur Hanger (UDH) |
| Cassette: | 10-51t (Long Cage - SGS) |
| Shifter: | Deore M6250 |
| Chain: | 12-speed HG: XTR M9100, Deore XT M8100, SLX M7100, Deore M6100 |
| Battery: | BT-DN320 |
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 through FedEX and USPS.
Most orders totaling over $59 are eligible to ship for free via an economy ground option of our choice.
Due to larger box sizes, handlebars and other oversized items will have an additional shipping fee.
Most bikes ship free within the continental US. Bike shipping to AK, HI, or PR is available at an additional charge 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.
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 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:
