Shimano Deore M6250 Di2 Upgrade Kit

Shimano dropped its latest rendition of Di2 drivetrains last year. Available in Deore, XT, and XTR, each strikes a different budget range, with variations in features, materials, and bling factor. We have covered and ridden the XTR and XT tiers, both of which are competitive options in the world of wireless shifting. What remained was the bottom of the totem pole.

You don’t have to splurge on an entire groupset to ride Di2. Shimano conveniently sells upgrade kits to convert to wireless. The Deore upgrade kit retails for $675, and we spent the past six months hammering it across multiple bikes to see if it delivers economic performance.

Tech Breakdown

The Deore M6250 Di2 upgrade kit includes a wireless RD-M6250 rear derailleur, SW-M6250 shifter, BT-DN320 internal battery, quick link, charger, and cable. It’s cross-compatible with a slew of Shimano’s current adjacent groupset offerings, both electronic and mechanical. I was supplied with several other XT components to pair with the Deore upgrade kit, and mix and match as needed.

The Deore Di2 derailleur is offered in an eMTB and standard version. There are two eMTB variations: 12-speed Hyperglide+ and 11s Linkglide. The standard derailleur is available in a single 12-speed Hyperglide+ option. All derailleurs come with a steel long cage (SGS) to pair with a 10-51T cassette. The eMTB derailleurs can also be hardwired to the main e-bike battery.

The Deore Di2 shifter is available in a band-clamp or I-Spec EV mounting option. Both are limited to single-click gear change operation, as in you can’t shift through multiple gear changes by pushing the lever past a single shift. You do still get the multi-shift feature by holding the lever down, which I wasn’t aware of until writing this (ha!). You also don’t get adjustable shifter lever positions like you do with XT and XTR.

• Deore upgrade kit - $675 USD
• Deore M-6250 SGS RD w/Battery - $435 | 520g
• Deore M-6250 IR Shifter - $140 | 86g

How does it stack up?

• XT upgrade kit - $860 USD
• XTR upgrade kit - $985 USD
• SRAM Transmission GX equivalent - $806 USD (Requires additional derailleur cage $125-$140) *also requires UDH compatible frame

I paired the upgrade kit with 165mm XT M8100 cranks, a 34t XT chainring, a 10-51T XT cassette, and a Hyperglide+ chain. I also installed a pair of Deore BL-M6200 brakes. Installation was relatively pain-free. Mounting the I-Spec EV shifter directly to the brake lever was a breeze. After mounting the derailleur to my Sentinel’s UDH hanger and shortening the chain following Shimano’s chain length guide, I paired the shifter and derailleur following instructions from a quick Google search. A couple of quick trim adjustments via the trim button on the shifter had the drivetrain running through gears smoothly. It sure does feel nice to pull a worn-out derailleur cable off a bike and not have to install a new one.

On The Trail

Testing began in late January and has spanned from Bellingham, Washington, to as far south as Santa Cruz, California. I’ve experienced most conditions imaginable, within reason. Only a couple of days in sub-freezing temps. But PLENTY of wet muck, and super dry and blown-out dust.

One of the first things I noticed was how well I got along with the shifter. Shimano has done an excellent job executing a wireless electronic shifter that somehow has the feel of its mechanical counterparts. I mean this in the best way. The levers have a nice tactile feel to the shifting engagement, and are positioned perfectly for my hands. This might not be the case for others who would appreciate the adjustability of the levers on the XT and XTR versions, but they worked for me. There wasn’t a learning curve to operate the shifter, as I’ve experienced with other wireless shifters. The fixed positions of the two levers were in just about the right spot for my thumb. I did try the XT Di2 shifter, and while the adjustable levers are nice, I ended up positioning them pretty much where they are on the Deore shifter. I also found I preferred the single-shift option of the Deore, as I tend to accidentally double-shift during gear changes on the XT.

The rear derailleur functioned very well for me across a few different bikes. It made contact with a hard object on more than one occasion and still remained true to its alignment. It has a ‘get work done’ sort of feel to it. A bit on the heavier side, but it’s nice to know it can take a beating and keep ticking. A testament to the steel derailleur cage—I was riding with a friend who also had a Deore Di2 drivetrain, who absolutely crushed the derailleur in a rare, rutted and rocky section of trail, rendering the derailleur inoperable. With a bit of coaxing, we were able to reshape the cage close to its original shape and get the pulley wheel reinstalled. It wasn’t pretty, but it totally worked. Not only did they ride out, but a month or so later, the same derailleur was still in use. Try that with a fancy carbon cage.

After six months of riding, functionally, the system has performed incredibly well. I’ve had it installed on a Transition Sentinel and Regulator eMTB. It really is a fuss-free drivetrain that is surprisingly durable. I did not take extra care with it, and it has been banged into more things than I care to admit. The battery charge only caught me out once, and that was purely due to my carelessness in not checking the light before going for a ride. When you can go weeks or longer without needing to charge, it’s easy to forget.

The shifting is crisp and responsive enough for me, and does so under load. This was proven time and time again when mounted to the Regulator, as shift timing sometimes takes a back seat while crosseyed and breathing through your ears, attempting heinous climbs. For an electronic option that is robust, the Deore shifter and derailleur combo is a great, budget-friendly choice. I really like that you don’t have to pony up for a full kit to get electric. And, it plays nice with all the other current 12-speed Shimano bits.

Here’s where things get a little sticky. You can read in nearly every other review that the derailleur is noisy due to the absence of a clutch mechanism. I experienced this immediately after mounting the parts to my bike. It didn’t take a rough section of trail for the derailleur cage to produce a healthy “THWACK.” There’s simply no getting around it. It really swangs, and when it returns, there is an audible confirmation that it has come home. Early on, I even went so far as to remove the b-knuckle bolt at the derailleur/hanger mounting point and install a crush washer to lock the derailleur body to the hanger to try to solve it. No dice. It was just as loud. There is also a very different sort of chain noise that occurs when things get hectic. The best way I can describe it is chain lash. I believe it comes from how much movement there is in the cage. I attempted to document the specific noise the derailleur makes for about a week. There’s something about the specific octave that just doesn’t register on a microphone.

This is not limited to the Deore derailleur. I mounted a full XT setup, and would say it’s about the same. Even the GS version (Shorter cage) of the XT derailleur with a 10-46T cassette. If you eliminate the clutch, there’s simply more movement that’s not managed. The tighter cassette and shorter cage derailleur setup does reduce the noise a bit, but it’s definitely still there. Additionally, during the test, I installed a SRAM GX crankset with an O-Chain, which helped a little but did not fully resolve the racket.

On the bright side, I never dropped a chain. I reached out to Shimano to discuss the new Di2 products, and they are aware that their choice to use a spring to tension and control the derailleur cage comes at the cost of increased noise.

Now, I’ve gone through waves of how much this bothers me. It’s quieter when the ground is soft, and louder when the trails are firmer. Some days it’s more distracting than others. I guess over time it’s bothered me less, and I’ve come to accept it. In the end, it’s hard to be too upset about it when the drivetrain still works day in and day out. I’ve spoken to people who’ve ridden it, and it’s either the first thing they mention or they’ve never noticed it.

My day job involves being acutely aware of how a bike feels, and noise plays a big part of that. I feel this is worth noting, as I’m likely a bit more critical than most about these things.

What’s The Bottom Line?

Today, I have the Deore shifter, XT 10-46T cassette, and XT GS derailleur mounted to my Regulator eMTB. I really like this setup for its durability and no-nonsense shifting. If Shimano offered the Deore Di2 rear derailleur in a GS (short-cage) option, I would happily be using it on this bike. eMTBs typically have a bit of extra audio playing in the background, so the derailleur movement tends to blend into the white noise.

If you’re someone who picks up on every little noise your bike makes, these Di2 drivetrains might be worth a demo ride first to determine how you jive with the additional audio track. If you’re not fazed by the noises bikes can sometimes make and are looking for a low-cost-of-entry electronic upgrade, I’d say it’s worth considering.

About the Tester

Lars Sternberg aka ‘LarsNBars’ - Age: 48 / Bikes became life in 1988 / Height: 5’ 8” (172.7 cm) / Weight: 165 lb (74.8 kg)

A lifetime of experiences packaged as a mountain biker. Lars learned the fundamentals of hardware thread pitch and differences of metric and imperial tools in the family bike shed at 8 years old. He learned geometry, radius and physics by building and shaping jumps and berms. Growing up at a time when it wasn’t socially acceptable to be both a skateboarder and a biker, he gravitated towards two wheels. Racing was an early and eventual lifetime passion. Bikes provided him a career in the industry. Having lived most of his life full throttle, he now enjoys riding in the middle of the pack, sharing experiences however possible, and finding balance in life.