Original Shimano parts guarantees that all components work perfectly for optimum performance and maximum safety and longevity.

For all the chatter about electronic shifting replacing mechanical, the place where people will love it or hate it is at the shift lever. Shimano rightly lavished plenty of attention when they designed the Dura-Ace Di2 STI Shifters.In order for the Di2 levers to work at shifting your bike, they must be used in conjunction with the Di2 front derailleur, rear derailleur, battery pack, and wiring kit. The most obvious advantage to going electronic is the fact that the cable routing doesn’t add friction to the system. No cables = no friction. Add to that the system is fast. Really fast. Faster than downtube shifting. 30% faster than shifting on mechanical Shimano Dura-Ace 7900. Better still, the shifting feel is much lighter. You can do it when you’re tired. You can do it with “weak” fingers. You don’t have to move your wrists or forearm.Unlike mechanical Dura-Ace, the Di2 shift lever blade doesn’t move inward. Instead there are two paddles behind the unidirectional carbon-fiber lever blade. The one closer to the handlebar still does the traditional shifting with the spring (aka onto smaller cogs in the rear, onto bigger in the front), and the one further does the traditional shifting against the spring (aka onto taller cogs in back onto smaller in front). They each have 2mm of travel. Each push results in one shift. Though if you’re coasting, you can “pre-shift” any number of gears, and the system will take up the shifting when you start pedaling. Shimano refined their STI lever when going electric. The levers are slimmer, closer to pre-STI levers, with some more ergonomic refining. Shimano shaved down their profile because they don’t need to allow for derailleur cable routing and the internal hardware it takes to precisely shift cable. The shift positions should still closely mimic mechanical Dura-Ace. The lever body, which they refer to as the “perch” has been better shaped for greater long-distance comfort.

Shimano’s M986 XTR Shadow Plus rear derailleur is a game changer. The innovative motion damping switch allows you to virtually lock out the bottom pulley of the derailleur, eliminating chain throw, chain slap, and extraneous drivetrain noise — in other words the drivetrain issues you have while riding rough trails at high speed. Simply flip the switch to its -Inchoff-Inch setting to remove the wheel or fine tune the shifting. Combine that with the unobtrusive Shadow derailleur profile, improved cable pull ratio and sealed top and bottom pulleys and you get the paragon of all-mountain derailleurs.

Shimano Nexus 8-Speed Tapfire Brake/Shift Lever.