# Mid Mount "manual" bottom bracket adaptor



## RockySpieler (Jan 8, 2012)

I have just brought a lapierre bosch ebike and wondered if I could convert to non-electric.

Obviously the battery just clips in and out. The images of ebike frames have a flange on them for the mid mount. 

Does anyone make a mid mount bb adapter for this flange?

I have googled it without success.

My idea is to swap and change depending on who i ride with, same derailleur, probably longer chain for a 1x crankset with bigger chainring.


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## highroad 2 (Jan 24, 2017)

The fabricator (I have built an airplane and road race car from scratch) part of me is intrigued by what you want to do.
Since I have a Bosch CX assisted bike I can envision the concept.
I highly doubt someone supplies what you are looking for but easily envision how to fabricate it.
All you need is the tube that the bottom bracket presses or threads into and weld tabs from the tube that will bolt to where the motor bolts to making sure the bottom bracket is concentric to where the center of rotation of the Bosch pedals currently are.
Working with steel would be easier to weld and could be done for not much heavier than aluminum.
You would need to pick a bottom bracket/crank arms design that is wide enough to clear the current motor mount and gets the new bigger chain ring in correct alignment to the cluster.
Does your Bosch drive use the idler on your Lappierre?
As long as the new chain paths clear with a bigger chain ring this should work well.
I envision you could make this swap in the time it takes to disconnect the wires and unbolt the Bosch and install a longer chain and pedal assembly.
Let us know how this turns out and much weight does it save and how does it pedal.


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## honkinunit (Aug 6, 2004)

With a Bosch or Yamaha, you would probably still end up with a wide Q factor crank to clear the motor flange, and getting a crank that would work might be difficult since many today are integrated crank/spindle designs. Apparently the Shimano drive has a standard Q factor so that might be easier. 

I am going to predict that within a few years there will be a 2 minute detachable system to drop the mid drive and replace it with a standard crank. Drop the battery, drop the mid-drive, attach the new crank unit, and you are off. 

Buy the bike without the motor/battery and add them later when desired. Seems like a no brainer to me. 

The haters are going to crap their pants. Is it an "ebike" if it has provisions for snapping on a motor/battery in two minutes?


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## highroad 2 (Jan 24, 2017)

Honk
I had no clue what Q factor was so google filled me in.
A highly technical term referring to ducks and the fact that they Quack and have a wider stanch to their feet.
It all makes sense.

I hope your predictions become true in that mountain bikes will become modular.
In seconds they can be converted to assist and returned back to non assist.

I started a new thread with the intentions of assisting a Santa Cruz Hightower I just picked up and looking for ideas


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