The Di2 actuators in the front and rear derailleurs of the current Ultegra series enable a significantly higher movement speed for a shorter movement time when changing gears and correspondingly rapid shifting processes.
The Shimano Ultegra Di2 FD-R8150 front derailleur speeds up the shifting process by 45 % compared to the previous generation Dura Ace model FD-R9150. The front derailleur which has also become more compact in its dimensions is thus not only faster than ever before, but also guarantees highly precise functionality under all conditions.
base, bracket: aluminium (painted)
chain guide: steel (plated)
outer link: aluminium (painted)
inner link: steel (painted)
STI lever: ST-R9250, ST-R9270, ST-R9160, ST-R9180, ST-R8150, ST-R8170, ST-R8060
crank: FC-R9200, FC-R9200-P, FC-R8100, FC-R8100-P
chain: CN-M9100, CN-M8100, CN-M7100, CN-M6100
accessory: SM-AD91 adapter
Weight: approx. 110 grams (manufacturer’s specs)
FITTING AND ADJUSTING TIPS
How to measure your foot length
- Stand with the heel to a wall and put a measuring tape under your feet
- Read off the measured foot length in millimeters before your longest toe
- If you are between two sizes, choose the next higher, because feet are minimally greater under load
You can also use our template:
Download the foot measurement template
Birkenstock products are offered in European sizes. Please reference our Size and Width conversion charts below to determine your SA/UK size.
Your feet should be able to move freely without your toes hitting the edge of the footbed.
Before trying them on, put one hand under the toe and one under the heel, then flex the footbed a few times. This will initiate the break in period and will your help your new sandals feel comfy sooner.
Open all straps and step into the footbed. Close the straps comfortably, leaving enough space to allow your feet the freedom of movement. Exhale and enjoy.
For the first five or six times you wear your new footwear, limit the time to just a few hours. This allows your feet and body to gradually get used to the contoured arch support as well as the straps and buckles.