Hi all,
I recently bought a 3 shoe polini clutch for my kids husky pro sr. I installed it like the directions said ()()()()(l , the flat washer at the bottom is .060 thk.
Here's the problem. The thing seems to engage at about where I think it should be (quite a bit higher RPM than stock, but not too high), but it seems to hit too smoothly, like its slipping some. It doesn't spin the tires at every turn like I see a lot of the bikes at the track doing. I thought maybe that one shoe was engaging before the others, so I took it back apart to check it out.
Here's what I found. I measured out each washer and stacked them within .002" of each other. The bolt shanks and clutch hub all measured within .001". Good. But the shoes are way off. They measure (from the OD of the shoe to the portion that contacts the hub) up to .014" different from each other. (2 shoes are within .003"). I also measured the depth of the counterbore (where the washers fit), and it reflected the .014" variation, indicating that there is a definite difference at the OD of the assembly, causing one shoe to hit before the others. Each shoe will have a different spring load on it when it touches the basket.
Here's what I did to hopefully correct this. Luckily, I am a machinist, so I just made up some new washers, one .063" thk, and one .074"thk, and assembled the clutch. This way they should all have the same spring load on them at the point of contact. But the shoe with the thicker washer is under more tension at all other times. (I sure hope I am making this understandable).
Is this an acceptable solution? I started wondering about the weight of the shoes being different, but havent actually weighed them. I even wondered if the shoes are supposed to be different thicknesses, and perhaps I am messing everything up. There are so many variables, I am not sure if I am accomplishing anything here.
I plan on trying the thing tomorrow, and I will post the results. If anyone has a suggestion I would surely appreciate it though.
Rich
I recently bought a 3 shoe polini clutch for my kids husky pro sr. I installed it like the directions said ()()()()(l , the flat washer at the bottom is .060 thk.
Here's the problem. The thing seems to engage at about where I think it should be (quite a bit higher RPM than stock, but not too high), but it seems to hit too smoothly, like its slipping some. It doesn't spin the tires at every turn like I see a lot of the bikes at the track doing. I thought maybe that one shoe was engaging before the others, so I took it back apart to check it out.
Here's what I found. I measured out each washer and stacked them within .002" of each other. The bolt shanks and clutch hub all measured within .001". Good. But the shoes are way off. They measure (from the OD of the shoe to the portion that contacts the hub) up to .014" different from each other. (2 shoes are within .003"). I also measured the depth of the counterbore (where the washers fit), and it reflected the .014" variation, indicating that there is a definite difference at the OD of the assembly, causing one shoe to hit before the others. Each shoe will have a different spring load on it when it touches the basket.
Here's what I did to hopefully correct this. Luckily, I am a machinist, so I just made up some new washers, one .063" thk, and one .074"thk, and assembled the clutch. This way they should all have the same spring load on them at the point of contact. But the shoe with the thicker washer is under more tension at all other times. (I sure hope I am making this understandable).
Is this an acceptable solution? I started wondering about the weight of the shoes being different, but havent actually weighed them. I even wondered if the shoes are supposed to be different thicknesses, and perhaps I am messing everything up. There are so many variables, I am not sure if I am accomplishing anything here.
I plan on trying the thing tomorrow, and I will post the results. If anyone has a suggestion I would surely appreciate it though.
Rich
