Hi, I purchased a bushing for wsk 125 b3 73r if I remember the vintage correctly. As for the outside dimension is an improvement, while the length has to be adjusted by grinding it on paper cut to the engine. Because sometimes after turning the engine, the box stands oaky. It all depends on the state of wear of our engine. Mine I had to grind 0.5mm to make the box turn slightly. Bronze very hard and resistant to wear I recommend