Hello,

Someone I know rides a Triobike Boxter cargo trike.

It was fine while she used it in a flat area, but the 250W, 90Nm Brose Drive S mid-drive motor is showing its limits in a much hillier area, and the kids are only getting heavier.

It uses an Enviolo Heavy Duty (380%), 135mm OLD hub with a Gates belt drive.

Replacing the original 50T + 24T cogs with a 46T + 28T did help, and the 46T will soon be replaced with a 39T, at the expense of riding on the flat.

Since the frame is meant for that mid-drive motor and it's just not possible to install eg. a Bafang BBS02/BBSHD, I was wondering about replacing the rear wheel with an (affordable, as money's tight) 750/1000W motor + derailleur, and just disconnect the mid-drive for when she'll sell that bike or move to a flatter area again.

Provided there are 135mm OLD 750/1000W rear hubs available, do you recommend direct drive or reducted? The former has the advantage of helping when going downhill.

Also, the frame might not accommodate a derailleur hanger. In that case, and considering the powerful rear motor… would using that bike with a single cog do?

Replacing the belt drive with a chain is worth it if that means more power to climb hills.

Thank you.