105 vs Ultegra vs Dura-Ace Di2 (2026): Weight, Price & Which to Buy

Short answer: all three Shimano 12-speed Di2 groupsets shift almost identically. 105 R7170 Di2 is the best value, Ultegra R8170 Di2 is the sweet spot for most serious riders, and Dura-Ace R9270 Di2 is for riders who want the lightest, stiffest and most refined groupset Shimano makes. The difference between 105 Di2 and Dura-Ace Di2 is about 500 g.

This guide compares weights, features, prices and who each groupset suits, so you can pick the right one for your bike and budget.

105 vs Ultegra vs Dura-Ace Di2 at a glance

	105 R7170 Di2	Ultegra R8170 Di2	Dura-Ace R9270 Di2
Speeds	2 x 12	2 x 12	2 x 12
Shifting	Semi-wireless Di2	Semi-wireless Di2	Semi-wireless Di2
Brakes	Hydraulic disc, Servo Wave	Hydraulic disc, Servo Wave	Hydraulic disc, Servo Wave
Approx. complete weight*	~3,005 g	~2,780 g	~2,510 g
Chainrings	50-34, 52-36	50-34, 52-36	50-34, 52-36, 54-40
Cassettes	11-34, 11-36	11-30, 11-34	11-30, 11-34
Extra hood button	No	Yes	Yes
Power meter crank option	No	Yes (FC-R8100-P)	Yes (FC-R9200-P)
Best for	First Di2, endurance and winter bikes	Club racers, sportives, best value per gram	Racing, climbing, no-compromise builds

*Approximate published weights for 52-36T, 172.5 mm cranks and an 11-34T cassette, including rotors and bottom bracket.

Weight compared, part by part

Part	105 R7170 Di2	Ultegra R8170 Di2	Dura-Ace R9270 Di2
Shift/brake levers (pair)	420 g	385 g	372 g
Crankset	767 g	749 g	685 g
Front derailleur	138 g	111 g	94 g
Rear derailleur	301 g	260 g	217 g
Chain	289 g	263 g	248 g
Cassette 11-34	360 g	342 g	255 g
Brake calipers (pair)	334 g	327 g	290 g
Rotors (pair)	253 g	196 g	204 g
Battery, wires, BB	143 g	143 g	143 g
Total	~3,005 g	~2,776 g	~2,508 g

The biggest savings with Dura-Ace come from the cassette (titanium and aluminium sprockets), the rear derailleur and the crankset. Ultegra saves about 230 g over 105; Dura-Ace saves a further 270 g over Ultegra.

Shifting: is Dura-Ace Di2 better than Ultegra Di2?

Not in a way most riders can feel. All three use the same 12-speed Di2 motors, the same BT-DN300 battery and EW-SD300 wiring, and the same E-TUBE PROJECT app with Synchro Shift and custom button mapping. Shimano quotes the 12-speed generation as shifting 58% faster at the rear and 45% faster at the front than the old 11-speed Dura-Ace Di2 – and that applies across the range.

Where Dura-Ace does feel different is the lever ergonomics and finish, the slightly stiffer crankset and the cassette's crisper feel under load. Ultegra and Dura-Ace levers also have an extra programmable button on top of the hood, which 105 Di2 does not.

Braking

All three use hydraulic flat-mount disc brakes with Servo Wave levers and more pad clearance than the 11-speed generation, so they are quieter and less prone to rub. Dura-Ace and Ultegra calipers are a little lighter; braking power and modulation are very similar. Rotor choice matters more than tier: 160/160 mm gives the most power for heavier riders and long descents.

Gearing choices

• 105 Di2 offers the easiest climbing gear thanks to the 11-36 cassette option – great for steep UK lanes and loaded endurance riding.
• Ultegra Di2 offers 11-30 for tight race spacing or 11-34 for hilly sportives.
• Dura-Ace Di2 adds a 54-40 chainring option for time trials and fast flat racing.

Because every 12-speed Di2 part is cross-compatible, you can mix tiers – for example Dura-Ace levers and derailleurs with an Ultegra cassette and chain to save money on wear parts.

Price and value

Shimano RRPs put Dura-Ace at well over double the price of 105 Di2. At Eminence Cycle Co. (October 2026) complete groupsets start from about £680 for 105 Di2, £995 for Ultegra Di2 and £1,700 for Dura-Ace Di2, depending on configuration – check the product pages for current prices.

• Cost per gram saved, 105 to Ultegra: roughly £1.40 per gram – good value if you race or climb.
• Cost per gram saved, Ultegra to Dura-Ace: roughly £2.60 per gram – worth it for racers and riders building a top-end bike.

Which Di2 groupset should you buy?

Choose 105 R7170 Di2 if…

• you want electronic shifting for the lowest price
• you are building an endurance, winter or gravel-road bike
• you want the 11-36 cassette for steep climbs

Shop the Shimano 105 R7170 Di2 groupset

Choose Ultegra R8170 Di2 if…

• you race, ride fast club runs or big sportives
• you want most of Dura-Ace's performance for much less money
• you want the option of a power meter crankset

Shop the Shimano Ultegra R8170 Di2 groupset

Choose Dura-Ace R9270 Di2 if…

• you want the lightest, stiffest Shimano groupset
• you are building a race or climbing bike where every gram counts
• you want the 54-40 chainring option or the best finish

Shop the Shimano Dura-Ace R9270 Di2 groupset

What about the new 13-speed Dura-Ace?

Prototypes of a 13-speed Dura-Ace (widely reported as R9300) were seen in the pro peloton in 2026. New generations launch at full price and with limited stock, and they may need new parts to work with your existing bike. If you want a flagship Di2 bike now, R9270 is the proven, best-value choice – and 12-speed Ultegra and 105 Di2 will stay current for some time.

Shimano Di2 vs SRAM AXS

SRAM AXS is fully wireless and offers wide-range 1x options; Shimano Di2 keeps a wired battery-to-derailleur connection, has a very long track record for reliability and generally costs less for wear parts. For a closer look at stopping power, read our Shimano Di2 vs SRAM AXS braking comparison.

Frequently asked questions

Is Dura-Ace Di2 worth it over Ultegra Di2?

For racing and climbing, yes – it saves about 270 g and feels more refined. For everyday riding and sportives, Ultegra Di2 gives nearly identical shifting for far less money.

Is 105 Di2 as good as Ultegra Di2?

Shifting is very close. 105 Di2 is about 230 g heavier, lacks the extra hood button and has no power meter crank option, but offers an 11-36 cassette.

Can I mix 105, Ultegra and Dura-Ace Di2 parts?

Yes. All Shimano 12-speed Di2 road components are cross-compatible.

Are these groupsets fully wireless?

No, they are semi-wireless. The levers are wireless; the derailleurs are wired to one internal battery.

What do I need to fit a Di2 groupset?

A Di2-ready frame with internal routing and flat-mount disc brakes, a bottom bracket for your frame and 11/12-speed Shimano HG road wheels. See our Shimano Di2 set-up guide.

Browse all options in our Shimano Di2 groupsets collection.