Having read what TrialsRfun has written about the clutch lightener by ARMAC I have fit one and it was easy to fit. The lightener was designed by a person that puts a lot of research into his products and are all field tested before release. As for oil coming though the gear shaft he needs to spend more time maintaining the gearbox, the clutch lightener will not fix a gear box with worn out bushes or worn main shaft, these need to be sorted before you can move forward.