It seems like the skid plate was a necessary engineering afterthought. I’ve only broken two alloy skid plates but the cooling fins (usually on the non-drive side) have chipped. A number of EMTB’s that I’ve seen have a similar issue. No cracked motor casing though.

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There’s been several attempts at a home built skid plate using different materials. (Carbon, plastic, etc). Both skid plates that I have broken have cracked at the weak point. (Trek Bosch CX motor).
I keep a spare alloy skid plate but haven’t needed it for a while. I carefully soften the chipped cooling fins with a dremel tool. I don’t know what the solution might be? Higher bottom bracket, heavier skid plate, different trail choice

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