First let me thank you all for helping in advance, I hope y'all can help me solve this little problem.
I recently swapped the rear hub on a Brompton, from the original single speed hub to a Sturmey Archer S-RF3. I think I have installed everything properly. However, the chain skips when I apply pressure to the pedals (when I ride it basically, or if I pedal it on the stand while lightly pressing the down the brake to simulate pressure). Without pressure on the pedals, it does not skip, although it moves a bit awkwardly if I pedal backwards. I think the problem may have arisen from the fact that we adapted a cassette cog to the hub, instead of using the original 18t cog that came with the hub. We used a thin 12t cassette cog, by dremeling the extra teeth. The chain tensioner looks fine, everything appears to be lined up properly. I am using a 1/8" chain, which is what I was using before with the single speed cassette hub. I tried using a 3/32" chain but the problem persists.
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