Shimano’s asking price alone assures that most riders who take offence to its Di2 XTR electric shifting system do not factor into its marketing strategy. Di2 XTR, if you can find it, will run you about $2800 for a complete two-by-eleven drivetrain. That’s a lot of cash for a small pile of parts. Consider that in a recent PB poll, an overwhelming number of responders placed the optimal MSRP of a mountain bike capable of elite-level performance between 3000 and 4000 dollars, and you may begin to realize that Shimano probably did not make Di2 for you. Why You Need Di2 XTR
Shimano Di2 XTR: Long-Term Review
Di2 XTR exists exclusively for the cycling’s top-level competitors and for top-level recreational shoppers. Unless you count yourself among them, your opinions about batteries on bikes, non-standard parts and Shimano’s pre-determined gear selections are wasted breath. Whether you are a naysayer or a supporter, the bottom line is that Di2 XTR shifts better and is easier to use than any derailleur bicycle transmission that has ever been mass produced for cyclists. Those who presently ride Di2 will no doubt agree that: “No. You don’t need it.” And, “Yes. You do want it.” Lazy readers can stop right here, because this entire story is summed up in those few short phrases. Riders who are curious about how Shimano’s push-button shifting performed over a long-term test, however, should find this review interesting.
Forget how Shimano’s electric shifting operates, clear your mind of its cost and perceived complexity, and you will find it very hard not to like. The rotary action of the shift levers are a near-perfect ergonomic match to the natural sweep of the thumbs. Shimano’s artificial mechanical click provides audible and tactile assurance that a shift has been called for, and (providing that it has been set up correctly) Di2 responds with a perfect shift - every time. There is no mechanical connection to the derailleurs. You ask for a shift and then pedal, knowing that, regardless of how much pressure you are putting on the pedals, or how your human form may be twisted around the cockpit, that Di2 will manage to shift to the next gear. There is no “maybe” in Di2’s vocabulary.
|My mechanical drivetrain does the same things - at one fourth the cost.|
We imagine that we can shift our mechanical transmissions with resolute perfection, but that is simply not true. A few months on Di2 are all it takes to realize how much knowledge and learned behavior a cyclist must assimilate before he or she can operate a mechanical derailleur system with surety. Consider for a moment, the actions that take place during a conventional cable actuated shift to a lower gear option:
First, you must remember to depress the lever just far enough to shift one gear (both SRAM and Shimano levers can shift multiple gears in one throw). Next, you listen for sounds that the mechanisms emit which give you verification that the shift is taking place. Then, you hold the lever in position until you are convinced that the shift is finalized and finally, you release the lever and check leg pressure to reconfirm that you have selected the proper gear.
All of the above may have been committed to muscle memory and subconscious action, but that does not take away from the fact that the rider must participate in each step in order to complete a perfect shift. So far, we are only using rear shifting as an example. The front changer’s reverse function, along with its distinctly different feel and sound, add further complexity to shifting a mountain bike’s transmission.
When a conventional shift lever is releasing cable to shift to a higher gear (smaller cog), it operates very much like Di2. You flip the trigger lever and forget about it, leaving the mechanisms to take care of everything necessary to make the shift. The only action required from the operator is to check leg pressure to confirm that he or she has selected the correct gear. Imagine the same action in both shifting directions, with an added measure of smoothness and precision, and you get Di2.
Conventional shifting also puts the burden of selecting the optimal gear range from a wide variety of options – some of which can create problems, or in extreme cases, destroy the drivetrain. For example: Di2 can shift a wide-range two-by or three-by drivetrain using a medium-cage derailleur, with a chain that is too short to operate when the transmission is cross-chained in the largest sprockets and NEVER make the mistake of shifting into the forbidden combinations.
Customization is also a unique attribute of Shimano Di2. By downloading Shimano’s e-Tube Project software to your PC (not ready for Macs, yet), you can program the shift levers to command any of the system’s functions. You can program Di2 shift like the paddles of a sports car with one side for up-shifts and the other for downshifts. You can program either the right or left-side buttons in Synchro mode to automatically shift both the front and rear changers. The functions of either button on one shift lever can be reversed, and given single or multi-shift powers.
Confusing? Having so many options can be daunting, but like suspension settings, you will quickly discover that only one or two choices are useful. I found E-Tube software to be easy to use, but Shimano has done its homework. After messing with a number of custom options, I opted to return to the default Synchro mode, where it stayed until I returned the bike.
It’s easy to imagine why cross-country pros, (who, I assume, are pretty handy with mechanical shift levers), have embraced Di2. Shifts are easier and more accurate, so a rider can confidently change gears more often to manage power output and, perhaps more importantly, make fewer errors towards the latter stages of a race when fatigue dulls reflexes and judgement. For both professional and rank-and-file-trail riders, Di2 simply means never having to worry about shifting. You place the order, turn the pedals and, “bzeeb, bzeeb, bzeeb” - Di2 handles it.Why You Don’t Need Di2 XTR
Truth is, Di2 doesn’t bring any major revolutions to the table. Shimano’s conventional XTR shifts well enough to make almost any rider happy. Di2 simply offers better shifting, and a Synchro Shift feature that allows two and three-by XTR drivetrains to be operated by one set of levers. Di2 in the 22-speed, two-by-eleven configuration offers 13 well-spaced gear options. That works out to one gear lower and one slightly higher than the SRAM one-by-eleven. I was also riding SRAM X1 during the long-term test period, and I put a lot of time on Shimano’s conventional XTR in both two-by and a one-by arrangements. In the end, I can comfortably state that, unless you absolutely need (or want) slightly better shifting and a wider, more evenly spaced gear range than a SRAM X1 drivetrain offers, you don’t need Shimano Di2.
Why state SRAM as the alternative instead of XTR? Because a Di2 two-by transmission, used in Synchro mode, is its direct competition. Paradoxically, once you have experienced the self-trimming feature and ease of shifting that Di2 brings to the table, you would never want to use a mechanical front derailleur. If Di2 can be considered revolutionary, it is because it demonstrates how cumbersome a mechanical front mech’ is – and thus furthers the case for eliminating them. But, presently Shimano lacks a competitive one-by option for XTR. If one compares gearing options, chain retention, and shifting stability of the two brands in a one-by arrangement, SRAM is the clear winner over Shimano in all three categories.
Shimano has been awarded patents for narrow-wide chainrings and has recently released an 11 by 45-tooth eleven-speed cassette that operates with Di2, so there is evidence that its mechanical and electronic one-by options will soon close the gap to SRAM.
But, as it stands, if you want a one-by drivetrain, buy SRAM - and if you want a two-by drivetrain with closer-spaced shifts and a slightly wider gearing range, buy Shimano Di2. Both give you best-in-category performance and both free up the left side of the handlebar for a dropper seatpost lever.How Di2 XTR Stood the Test of Time
Shimano’s Di2 XTR earns the high marks for reliability and durability – and after a full season of thrashing, all indications say that Di2 will hold up better than mechanical XTR. Check out Mike Levy's review of Shimano's M9000 mechanical XTR
for the full story. Wear on the cassette cogs was slightly less on the larger and smaller sprockets and about the same in the middle ones – which stands to reason, because the computer manages the two derailleurs to keep the chain in the middle of the cassette, which eliminates the most offending cross-chain combinations. Good thing, because new XTR chainrings are P R I C E Y items to replace.
The derailleurs cranked out shifts without fail and with no need for an adjustment for the first three months of testing. After bashing against some hefty boulders, however, the rear changer needed a slight adjustment. Di2 derailleurs are adjusted using the small display. After selecting the adjustment mode, tapping one paddle will move the changer left, while the other moves it right. One adjustment in an entire season of riding was pretty hard to believe.
The front changer was equally reliable. Its motor is massively powerful and can force the chain up to the larger chainring under full climbing torque - and that is how I used it. I never let off the gas to make its job easier in either direction and, except for one rather embarrassing moment, it never tossed a chain, left me to deal with a grinding noise, nor missed a shift, The big moment came immediately after I loudly proclaimed during a popular group ride that I had never tossed a chain - then, boom! It shifted the chain off the small ring and into neutral. I swallowed my pride, made a tiny adjustment to the inside stop and never had another issue.
Water and mud did not adversely affect either changer, nor was there any lapse in service that may have been caused by a leaky fitting. Shimano must have a Di2 test submarine in their research and development wing. I did have some issues with the tape that is used to conceal the wires where they pass under the handlebar. Once dust sneaks under the adhesive, it starts to look natty. The tape did remain in place, so functionally, it was a win for Shimano. I purposely photographed the components unwashed and beaten by the elements, but the changers did clean up well.
|Battery life was so good (Shimano insiders say 20 hours of race-shifting between charges) that I actually forgot that I had to charge it the first time and nearly ran it down to nothing.|
Battery life was so good (Shimano insiders say 20 hours of race-shifting between charges) that I actually forgot that I had to charge it the first time and nearly ran it down to nothing. There is a USB port in the display that hooks up to the Di2 charger, so there is no need to remove the battery. I charged the system twice in five months and the indicator said I had a third of a charge left when I sent the bike back.
Noisy cassette cog:
E-Tube program: Good marks to Shimano for making its programming software easy to learn and intuitive to manage. Sadly, it is still PC only. A smart phone app would also be great.
To beep or not to beep: When I first started in with Di2 XTR, I hated the warning beeps that sound when you have reached the last cog of the cassette and also before the system executes a double shift (both derailleurs simultaneously). I used the E-Tube program to eliminate the warning sounds, but after a month, I wanted them back. Turns out, it's nice to know that information.
Not something that I was expecting from Shimano, the chain seems to struggle slightly when pedaling hard in the large chainring and the second largest cog. There seems to be some noticeable drag in that option as well.Syncro shift modes:
Shimano nailed it. Don't bother trying to outfox the computer and don't bother with a left-side shift lever. Depend upon either of the two default Synchro options to select the proper gear sequences and forgettaboutit.Pinkbike's Take:
|There is a reason that top sports car makers have abandoned the stick shift and adopted electronically assisted dual-clutch transmissions and paddle shifters. They shift faster and more accurately and, more importantly, paddle shifting removes much of the workload from the driver. The same can be said for Shimano's Di2 XTR. If money were no object, only nostalgia would be a reason to choose mechanical shifting on a mountain bike - or a stick shift on a road car. |
Is Di2 for everyone? Certainly not for the budget minded. Bike makers could offer a substantial suspension or chassis upgrade for the additional expense of Di2 XTR, but at the price point that Di2-equipped bikes will be offered, it would be as difficult to defend the retail cost of any other component. The bottom line is that Shimano's take on electric shifting will make you a better rider, and that is true whether you are a top pro or a rank amateur. No. You don't need it. Yes. You will want it. Look no further than SRAM for verification - their electric mountain bike group should debut this spring. - RC
View more images in the review gallery.
If I was given it, would I use it and like it? Yea, probably.
Would I spend money on it? No.
I can see the appeal, the smart and smooth shifting is pretty appealing and I'm sure the next gen won't even require a shifter (like an automatic car.) but the problems for me are: hard to troubleshoot and fix myself, if I forget to charge and run out of juice, the battery will degrade over time, and it's too expensive.
Honestly I'm more excited to see a light, reliable, and inexpensive internal gearing option. That's where it's at IMO.
RC - before you call me a luddite, I am usually early to adopt new bike tech after some critical thought. New tech is great, but I can't get behind this one at all. Trying to convince the masses that this is what they actually "want" and create demand for a ridiculously expensive consumable component just reeks of marketing for future XT level kits. Your parallels to paddle shifting in sports cars are unfair- sequential gearboxes work flawlessly; the derailleur is a 100+ year old system that has inherent fundamental issues, no matter how refined.
Saying that we should "look to SRAM for verification" is ridiculous, of course they want to compete with Shimano, tell us we want it and sell product. Don't forget the saying people - never ask a barber if you need a haircut!
But yeah not as many
good luck with your di2s loool
you're drunk. go home.
And here we have the derailleur drivetrain: a hunk of shit.
We bitch (justifiably) about all these new standards, but holy crap, as soon as someone figures out a gearbox or Shimano creates an MTB-able Alfine that's way lighter (and rear suspension and chain growth etc) all of what we have now will be ancient history. Then Boost 148 really will not matter; you can get those extra 3mm spoke bracing angles since you'll only have one cog on the rear and not a cluster of shit.
Back in 1993 while still in school I worked every hour I could at my lbs so I could build up a non branded British eagle frame with bits ordered at cost thanks to working there.... Over the next 20 odd years I've spent hours on scouting ebay, perfecting the last minute, slowly upgrading, buying and selling different bikes/frames/bits etc, being unlucky enough to have one bike nicked but lucky enough for the insurance to pay out, doing deals with shops I've built up relationships with, ordering parts/bikes cheap from Germany, not to mention the hours grafting as a sparky to afford the upgrades.... All to the point where a year or so ago I could afford to build myself a top of the range Bronson, great bike and I loved it.... But you just know as your pulling up to the trails with the bike on the roof there's a load of people in the car park thinking 'look at this flash d***head with his carbon Santa Cruz'
Yeah there maybe people who've just taken up the sport and gone an bought the most expensive bike they can find.. BUT then there are also some that have got here through years and years of searching and gradual slow upgrading. If you are one of the latter then enjoy your expensive bike and f**k the haters!
don't. Doesn't mean sh$t.
Am I allowed to say that I disagree with the Sram being best option though? I own XO1 and its performance is reliably unreliable at best.
Relatively speaking, this system's battery isn't cost prohibitive. But it probably will be cost prohibitive and impossible to find when it does die in 5 years after they've moved on to a different type that's no longer compatible.
I suppose I personally am just annoyed with expensive products with rechargeable batteries that don't last. My beef wasn't necessarily with this particular system's battery, just batteries in general. Like cordless drills - the are nearly worthless with a bad battery. And, I've been through several mtb rechargeable lighting systems that once batteries were kaput, they were nearly useless. I have a nice streamlight flashlight that's only a few years old...guess what? Toasted battery.
dear americans, you have to learn to drive a car properly. you know, through turns and stuff.
Have you ever been to the alps in the winter? have you ever seen the tourists stuck on the smaller side streets with their late model SUVs while the locals drive circles around them in their small front wheel driven cars? Well i spent the first 32 years of my live exactly there doing exactly this. It was fun.
What i loved most was seeing an BMW x5 not being able to get going on the slightest uphill instead just having his breaks glowing in the dark because the ESP and traction control is working sooo well.
Talking about hot brakes, since i moved to the US every time a drive down a mountain road i have that smell of overheating brakes from the guys in front of me in my car... yeah automatic, good job, so much better.
and so you dont get the wrong idea, i actually run Di2, its cool but you cant really compare it to a freakin automatic gear box in a car.
you forget how to react. or you never learn it. automatic transmission, no clutch and snow/ice is the worst...
btw all our ski roadtrips are done with a diesel 3 series, manual, rear wheel drive and no esp at all times.
A high percentage of new cars in 2025 will be 100% electric.
and will have/need no gear box whatsoever...
When i am going somewhere long distance i usual get me a rental car which in the states is always automatic.
These f*ckers just drive me nuts when i am rolling up a hill using cruise control and they down shift and start revving up like i am fighting for pole position in an f1 qualifying knocking my had backwards against the headrest every time...
Why is it that a 30 year old car that once had 200 horses, a good amount of them probably escaped throughout the years, has no problems cruising up a hill at 65 miles an hour, but a brand new luxury automatic has to down shift in to 3rd gear like its a freaking 50cc scooter every time a hill appears on the horizon?
On the same note why does and modern sports car needs to extend a freaking spoiler at 30 miles an hour when my 30 year old piece of junk can easily do over 100 mph without wings and sh*** coming out of the trunk and is not lifting off either? Are the aerodynamics on these new cars so bad you cant drive to grocery shopping without looking like you just coming for an audition for fast and the furious 48?
its just a weird world...
Today, most cars (I'm talking automatic trans) from mid-low end all the way to high end like the automatic version of your 635 have 5-8 gears, with the highest 2-3 being overdrive. Today's version of my Audi will rev at or below 2000rpm when in top gear at 70mph, purposely limiting the power on hand in exchange for better fuel economy. Plus there's all sorts of engine tech going on with valve timing, turbos, etc to purposely weaken the engine--while you aren't paying attention and just cruising along on a flat stretch of road at a constant speed--all in the name of economy. In a better car you won't notice the weakling your motor has become because the instant you step on the gas all of that tech switches from economy settings to performance settings, pumping fuel to the fire for as long as you ask it to before turning into a neutered milquetoast once again.
But tech is expensive, and what better way to cut corners (even on luxury brands) than eliminating the tech and claiming to accomplish the same results using something you already have to have in the car anyway -- the transmission. The fact is, most late model automatic trans cars don't achieve top speed in their highest gear. The top couple of gears are now solely there for fuel economy. The reason your luxury rental downshifts into 3rd is because that's the gear which creates the revs required to put the motor at the peak of its power range. When the driver no longer wants the motor to be Mr. Hyde, everything goes back to the super economical, quiet, boring (and unfortunately default) Dr. Jekyll state.
Currently, my home has an Sti (manual) and a Honda (automatic). I curse the Honda every time I have to drive it.
"Shimano Di2 XTR: BE GONE, PEASANTS!"
And this d0ouchebag drove to the trailhead in a 2017 Porsche Cayenne Turbo GTS.
I hate these dudes.
XTR Di2: Bring it on. This is awesome. Technology moves the needle forward, bicycling included.
Dura ace di2 rear derailleur €480
Ultegra di2 rear derailleur €170
Xt di2 rear derailleur???
Do xt di2 should be cheaper than x1, no f'ing around with shift cables, it might even be worth the risk of smashing one every 18 months. Sounds good to me.
In that case upgrading the rear derailleur and rear shifter wouldn't have to cost too much.
*sarcasm has not been included in making of this comment
Have you tried the OneUp Rad or Radr cages yet? They are much more robust than the standard cages shimano mechs come with. I have a Radr cage on a Saint derailleur and a expanded 10 speed 11-42 cassette, with a direct mount hanger, and it does not leave much room for wanting in any area. Price, durability, repair-ability, shifting performance and gear range. I am in absolutely NO rush to change this drivetrain setup.
And don't forget that the breakable derailleur hanger is there for that too.
There will always be some competition (Shimano XT 11sp for example) but you can say that Shimano still concentrates on optimizing 2x solutions!
What a time to be a mountain biker!
There are very few people for whom the $1,000 upcharge over a nice mechanical 1x will be worth it if compared to, say, the same money invested in skills training at Whistler (to take a cue from RC's "Ask Pinkbike" advice given yesterday). For most of us, that's an investment that would make a much bigger impact on how much we get to enjoy our riding than the better shifting experience and range that comes from this. If you're already maxed out on that aspect of things, and if money is not the limiting factor, then yes, you might be the target market for this.
Meaning: quality control will make or break this product.
At this price point they can't have any sanfu's from the factories making the product.
Why make it 11-40, when SRAMs offering 10-42?
Oh, you mean I should get a front derailleur again? Good idea! Just lost alot of dead weight when I threw that in the garbage, why do i want it back?
It's not a finished product yet!
It's like. Hey! You want electronic gearing that's not as good as a traditional gearing? And wait! It costs a shit load of cash and it's also heavier! Sounds tempting?
Byt hey, I understand Shimano. They have to do something. They have to evolve too.
Maybe in 5 years there's something awesome coming and this was the first attempt.
Still not bought a 29er, a fat bike, a 650b, carbon rims and many other must have items to make me a better rider. Knew it was not my fault for being an average Joe all along.
My favorite comment, so much for narrow wide rings and clutched rear derailleurs keeping crossed chains on without a guide as promised.
Looking forward to XT Di2 at a more palatable price. I did a spin class DA Di2 and learned just how clunky and antiquated our best mechanical derailleur systems are. Mind you a ride on an Alfine hub will show you that too at a fraction of the cost.
Ultimately as mentioned derailleurs are 100 year old tech and sooner or later someone is going develop an internal system that provides much of what Di2 does with a cable and no batteries at a fraction of the price. Now that Shimano has their Steps E drive in production maybe they will get to work on the internal shift system of the future. If you think it can't or won't ever happen think about how many times game changing tech has been added to those original fat tire single speed coaster brake clunkers Gary Fischer started with to get our bikes where they are today.
In case you ride hard often and wanna get as much pleasure as you can better to stick with top end components
As evidence, my buddy bought a used GTI with a stick rather than a new GTI with the paddle shifters.
Just my 2 cents...
Conventional systems no likey when you do that
Still electronics shifting components looks awesome but I think production cost and retail are too expensive.
Where do I even start with this...smh
use ctrl+F to find in page. I use it all the time
So if you have 26" wheel bike, with 170mm cranks, a 30 tooth front, pedalling at 90 rpm with an 11-45 cassette you can do between 7.5km/h and 30.6km/h. If you have a 10-42 you do between 8km/h and 33.6km/h. Adjust that front chainring to a 28 and with an 10-42 you are doing between 7.5km/h and 31.4km/h. Hence, more range with a 10-42...
So with the former you have a 420% difference between your highest and lowest gear, and with the latter a 409% difference.
You don't need a calculator to see that the jump from 11 to 10 is a larger percentage than the jump from 42 to 45.
I did need a calculator for response above, but I only used that approach because I think that's the most convincing way to prove this to someone who needs proof.