About Shimano Dura Ace DI2 Electronic Shifting
What is Shimano DI2?
DI2 uses electronic signalling between the shifters and the derailleurs. Each derailleur contains an actuator that provides precise and instant shifting, far better than you can manage on your own.
When bike mechanics buy...
When a jaded bike mechanic raves about them and buys, you know they work great. They have ultra long battery life, auto-trim, and mis-shifts are banished.
See the Battery Life page.
There’s no going back to crude mechanical cables for me.
- Perfect shifts every time — instant, precise shifting, with no cable flex or anything to degrade over time. Well, almost all the time. I had the chain drop off the small front chainring once, and the initial setup must still be done precisely.
- Auto trim — no more noise from rubbing on the front derailleur.
- No cables to lube or replace — the cables are lightweight, just enough to carry an electrical signal from the levers to the derailleurs. Think about that— no maintenance.
- Shift without thinking — with DI2, you’ll rapidly forget you’re shifting, because there are no adjustments to make, no extra torque to shift to the big chainring, etc. It’s all much more fluid.
- No cable maintenance — there are no mechanical cables to lubricate or replace— long term reliability and lower maintenance.