Since Shimano made the switch to 12-speed Di2 for their top-tier road groupsets there’s been a lot of speculation about what technology would trickle down to their mid-range equipment, specifically 105. There were plenty of rumours but finally, Shimano 105 Di2 is here. At 99 Bikes we’re guiding you through what’s new with the groupset and offering you the opportunity to order Shimano 105 Di2 and be one of the first in the country to get your hands on the highly-anticipated electronic groupset!
Celebrating 40 years since its first introduction in 1982, Shimano 105 has made perhaps the most radical jump in it’s development since the beginning. An extra cog and the move to not only electronic shifting but semi-wireless to boot. While this is nothing new for Shimano and we’re plenty familiar with Dura-Ace and Ultegra 12-speed Di2 105 had traditionally been the groupset of the people at an affordable price point. Shimano have finally opened the door of electronic shifting to more cyclists than ever with 105 Di2.
The new 105 Di2 shifters have been considerably slimmed down and now sit easier in hand than the outgoing 105 R7020 mechanical units. For those with smaller hands that’ll come as music to their ears as the previous hoods while providing ample grip could often feel a bit cumbersome. Those shifts are now easier than ever too thanks to the lack of movement in the lever, it’s as simple as the touch of a button. If you’ve any dexterity issues you’ll find Di2 an absolute game changer, you’ll be left wondering how you ever lived without it. Thanks to the lack of mechanics every shift is perfectly optimised and consistent. The worry-free approach theme continues thanks to the battery life of the shifter itself lasting around 3 years, paired with wireless technology the only cable that needs to be routed from the shifter is the brake hose. That ensures your cockpit is kept clean and those fiddly integrated bar/stem systems become a doddle!
Thanks to a new piston design, the Shimano 105 Di2 12-speed braking system has been completely overhauled. With 10% wider pad clearance to avoid pad rub and the dreaded brake squeal along with more braking modulation than ever before. Shimano even simplified the bleeding process by relocating the bleed nipple allowing for brake bleeds to be performed without the need to remove the caliper from the frame.
Shifting is taken care of thanks to the E-Tube equipped front and rear derailleurs. Intuitive shifting in the form of Shimano Syncronized Shift even allows the rider to operate both derailleurs with a single lever if they choose to. Fully customisable via the E-Tube Project App, both front and rear derailleurs are automatically selected for the most optimal gear combination. You can do things the old fashioned way too and set the shifters up just how you like them. With approximately 1000km run time between charges you shouldn’t find yourself running out of battery either.
The 105 Di2 rear derailleur is compatible with a 36t cassette allowing for a huge range, sub 1:1 in fact when paired with the 50-34T chainset. This means even the steepest slopes can be ridden with ease. Now the central hub of the system the rear mech includes the charging port, indicator LED’s and adjustment switches while a slimmed-down design reduces the chance of damage should the unthinkable occur.
Up front and the 105 Di2 front derailleur is a clever bit of kit, you can shift at the rear without the need to trim the front mech. It also lets you shift under load so you keep your all-important cadence going no matter the situation minimising the risk of chain drop.
Cassette choices are simple, there’s 11-34T and 11-36T which provide an ideal range of ratios without huge gaps between shifts. These are compatible with 11-speed and 12-speed freehub bodies so there’s no need to worry about existing wheel compatibility. The 11-36T 12-speed cassette offers a 327% range which is quite frankly all you should ever want for road riding!
The 105 Di2 Hollowtech chainset is a piece of art that looks strikingly similar to the top-tier Dura-Ace equivalent. Offering a balance between efficiency and weight the Hollowglide structure allows for better power transfer ideal for racing to the next signpost. The chainset comes in 160, 165, 170, 172.5, 175mm lengths and 50-34T or 52-36T options.
While Shimano 105 Di2 might not be for Weightweenies it’s certainly now heavyweight with the equivalent SRAM Rival ETap AXS coming in at around 120g heavier. Weighing in at 3067.7g 105 Di2 weighs around 360g more than Ultegra Di2 12-speed and 560g heavier than Dura-Ace Di2 12-speed. Below is a table outlining the individual component weights.
| Component | Weight (grams) |
| Rear Derailleur | 302 g |
| Front Derailleur | 142 g |
| Cassette | 361 g |
| Chain | 252 g |
| Chainset | 765,6 g |
| Bottom Bracket | 77 g |
| Shifters | 423 g |
| Brakes | 282 g |
| Brake Hoses | 110 g |
| Rotors | 285,6 g |
| Battery | 53 g |
| Cables | 14,5 g |
| Total | 3067,7 g |
The new Shimano 105 Di2 R7100 groupset brings Di2 shifting to a new affordable price point. With functions and tech inherited directly from their Dura-Ace and Ulterga drivetrains, 105 Di2 is the culmination of years of research and development. The biggest selling point perhaps however is the price. Shimano 105 Di2 R7100 12-speed is available to order from 99 Bikes from just £1,677.89 making it the most affordable Shimano Di2 on the market and opening the door of electronic shifting to an entirely new market. Whether you’re training, touring or racing Shimano 105 Di2 is perfect for all road riding applications.
