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kanedog
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Guess I should take a closer look at mine and see.
What is causing this?
It’s gonna be a combo of engineering blunders. On their own, things will last a bit longer, but will eventually fail. Add all the ingredients in one mixing bowl, failure is imminent. The cover is super wimpy so it most likely letting the towers flex simply from the weights overcoming the spring pressure. The cover bushing/spider nut contact before the sheaves touch each other. The towers get pulled inward toward the shaft. This is bad. When some nice harmonics are added, it will attack the most stressed part of metal. The clutch doesn’t really stand a chance. Each cycle and full shift cycle progressively weakens the towers until BOOM! Thar she blows.
A heavy duty trinket, like a 911 cover(I have no affiliation) but not a Bikeman, will help keep the towers from flexing. It holds the tower in place and makes the clutch stiffer and firmer, just how we like it.
It will be either the spider nut interference and/or harmonics and/or flexing wimpy cover. All are clutch killers and all need to be fixed or it will keep happening.
The 2020’s may have fixed this issue. They fixed the harmonics issue but I haven’t held a 2020 clutch in my hand for official Kanedog approval.
Notice the inner belt marks only using less than 50% of the clutch. Lower gearing will allow more use of the clutch sheave. This defined dark to light marks could also be where the helix shift point occurs. The belt could be slipping down low because of too high of gear ratio. Whatever it is, it’s a bit off.
Notice the yellow arrow and belt mark. This is where the cover/spider nut stops the clutch from shifting. The belt marks should be all the way out to the edge for full shift out. The belt length and center to center distance may not work together anyway. The belt had to be changed to accommodate the roller bearing and tight deflection so who knows what shortcuts were taken.
Basically, there are a ton of flaws with this drive system. It’s such a bad design all the way through.
The inner belt marks indicate that the rider rides in low speed riding, like tree riding for instance. The sled doesn’t get wound up on a long pull much.
The outer marks indicate the rider goes from low speed to wfo full pin, with a light load fairly quickly. Like using wfo to help bring the sled around on a whip. There are not much belt marks between the outer and inner wear patterns. It’s like the sled is tree riding and then the odd burst of unloaded sled wfo and not much in between. I would guess by the dirty clutch compartment(lots of riding) and belt marks this would be Calebs’ sled. KBI case solved once again.
The above are my beliefs.
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