Hi All,
Have a small problem with gears on my trike build. Three chain rings at the front, 7 speed on the rear cassette. As I did not have all donor parts (the chain rings, chains and rear derailleur are all new parts) only the 7 speed cassette is old parts. In terms of shifting gears it is all working sweet.

My problem comes on one gear sprocket on the rear cassette when under load (ie. Going up hill). The chain slips and skips on the one gear.

I suspect that I should either change the sprocket, or change out the whole cassette. A new one will only be £20 ish. But all adds to the total cost of the build. So before I do that, does anyone have any thoughts please ?

Everything is clean and tidy so not a dirt issue.