Hello everyone!

After several years and thousands of miles of commuting by bike, I recently installed a mid-drive e-bike conversion kit on my gravel bike. For the most part, the experience has been absolutely fantastic. However, I'm having some pretty frustrating difficulties with the drive-train, and I've exhausted my expertise.

The bike came with Shimano Claris, which is certainly not the most robust drive-train. When I first installed the kit, the chain was skipping over the cassette pretty much any time the bike went under load. The cassette already had several thousand miles on it, so I replaced the entire drive-train (chain, cassette, and derailleur) with brand new Claris components. This worked great for about 200 miles (~4 days), but then the cassette started skipping again.

I replaced the cassette again and pretty much immediately snapped a chain. I again replaced the chain, and about 50 miles later snapped it again. I brought it to a local bike shop, that once again replaced the drive-train (this time with higher-end components) after noticing one of the cassette rings had been cracked down the middle. I brought it home, only to snap another chain within 50 miles, stranding me several miles from home.

Funnily enough the components are cheap enough that I'm still spending less than I would on gas/car maintenance, but obviously this is something I want resolve regardless.

I'm in the process of looking into more robust drive-train options. My priorities are durability and low maintenance cost/difficulty, but I don't care as much about weight/efficiency. I'm putting several times the power you'd typically put through a drive-train, so I'm not sure most of the go-to higher-end options for typical road cyclists would be sufficient.

I've seen some people discuss more exotic drive-trains like belt drives and internally geared hubs. Those sound intriguing, but also very complex to retrofit. It seems to me like there has to be some sort of drive-train with a larger/thicker cassette and chain, at the expense of having fewer gears. Perhaps something like a belt drive really is the safer option?

I'm willing to spend quite a bit on this, but I want to be confident it would actually be a reliable long term solution.

I appreciate your advice here,