External Battery mount

The BM-DN100 external battery mount lets you use the older generation SM-BTR1 on your bike and take advantage of Synchronized Shifting - this battery mount contains updated hardware that enables Synchro-shift. If you cannot fit the BT-DN110 internal battery in your frame, this external mount and SM-BTR1 is what you'd use.

It is available in three versions, so you will probably be able to find one that suits your bike. The BM-DN100-S is the short version, supporting internal/external wiring. The BM-DN100-L is the long mount while BM-DN100-I is a long mount meant for internal cable routing. Have a look at the BM-DN100 different sizes pdf for more information.

Use the long version if you have the space for it. The long mount lets you use an external battery and a bottle cage. The short mount is meant for small frames or frames that cannot accommodate the long mount.

All three versions are fastened using M4 x 10mm (or 16mm) screws.

BM-DN100 battery mount

Details & specifications

Shimano model codeBM-DN100-S, BM-DN100-L, BM-DN-100-I
Shimano model nameExternal battery mount
Weight50 g
SeriesUltegra 6770, Ultegra 6780, Ultegra R8000, DURA-ACE 9070, DURA-ACE R9150, GRX, MTB
Downloads BM-DN100 manual
BM-DN100 Different sizes
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Shopping links

Are you looking to upgrade your bike using this component? We've added shoppings links to this component's Amazon and eBay pages. Click the images below to view the Amazon product page or eBay search results.

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Additional images

BM-DN100 short

BM-DN100-S (short)


BM-DN100-I (long, internal)

BM-DN100-I (long, internal)

BM-DN100 battery mount

BM-DN100-I (long)