happycheapskate
Active Member
I have figured out how the infamous chain tensioners could cause the accident described some on this board (going into the spokes and wrecking the wheel).
The chain tensioner/idler may rotate on the chainstay if it is not welded or pinned with a set screw, esp on bikes with narrow chainstays such as a ten speed road bicycle.
Also, if the torque of the motor (esp at low engine speeds, such as starting) moves the axle forward a little, it can skip a tooth on the driver cog and jam in the driver cog cover (where the little clutch arm is). This locks the chian while the wheel is turning, pulling hard on the idler, and possibly dislodging the wheel axle or pulling the idler hard, which can drive it into the wheel.
I really thing the solution is to use a chain tensioner if possible, the kind that pulls the axle with a bolt welded to a washer.
I like the auto tensioners that mount to the seat tubes, but I cannot find these in the catalogs I have checked so far. Please respond if you have one and tell where you got it and how well it is working in service.
The chain tensioner/idler may rotate on the chainstay if it is not welded or pinned with a set screw, esp on bikes with narrow chainstays such as a ten speed road bicycle.
Also, if the torque of the motor (esp at low engine speeds, such as starting) moves the axle forward a little, it can skip a tooth on the driver cog and jam in the driver cog cover (where the little clutch arm is). This locks the chian while the wheel is turning, pulling hard on the idler, and possibly dislodging the wheel axle or pulling the idler hard, which can drive it into the wheel.
I really thing the solution is to use a chain tensioner if possible, the kind that pulls the axle with a bolt welded to a washer.
I like the auto tensioners that mount to the seat tubes, but I cannot find these in the catalogs I have checked so far. Please respond if you have one and tell where you got it and how well it is working in service.