Modding a Brompton bike to fit a CYC Mid Stealth mid drive


1 mW
Sep 3, 2023
Hello all, i have a project to fit a CYC Stealth Gen 3 into a Brompton frame, without affecting the fold.
This is the specs of the motor : 1707187425709.png
This is and example of the bike :
I've made a red mark to represent the center pedal to the top tube around 180mm
Blue mark is the largest space 100mm
Thing is I've made a 3D little model and its seems i would have to remove a couple of mm of metal to actually fit the motor there since is a round 74 mm motor. and i have in the middle of this triangle about 68mm (where the bottom of the motor would hit.

The CYC Stealth Gen 3 as a detachable controller so its possible to mount the motor there, should it fit.
Eventually, if this get real, ill make an other post for integrating the CA3 to this setup.

The goal of this project is weight, as hub drive that fits this bike stock are weak (EU ones) or the one front grin is pretty powerful (its the one im running) but it makes this bike heavy and unbalanced when folded. So im looking to equip it with a mid drive and a set of carbon wheels to make this bike the best eTravel bike for touring (its already pretty dam good) but at 40 pounds ish its not the lightest right now. (about 25 pound without hub motor)

Anyone with bike modding experience could tell me if its safe to remove a small round section of the support steel bracket (without cutting thru it) to fit the motor ? (btw bike is all steel UK hand made) so its pretty sturdy bike.
I Hate my Cyc pro 1 Gen 2 with ASI BAC 855 BT controller that worked half ass for two weeks. Cyc lead me around for 2yrs. Then they broke down and offered to sell me a x6 controller for 60.00 and 30.00 shipping. That's on top of the $1,200 I paid and waited for a couple months. That b a c 855 controller was known to break up and they knew it. They just led me around in circles download this try that stick a paperclip in the connectors to short out the display. Nothing worked and they kept trying to have me redownload do the QR code I got sick of it and I just stopped till I went after him again with emails do they sell me a controller X6 for 60 bucks. Now I look back I was a fool.
Plus I hate the noise.