ball bearings race problem

Discussion in 'Frame Mounted Engines' started by cpuaid, Apr 19, 2009.

  1. cpuaid

    cpuaid Member

    i have repacked my ball bearings race twice already but after 80 - 100 miles , the 53 bearings spill out again. the woodruff key on the clutch gear has also been replaced. this time i will replace the balls thinking that some of them have been worn down slightly enough that any sudden jerk of the clutch assembly would make them spill out.
    i put in 100 miles commuting a week and the motor still runs perfectly. if the clutch remains unreliable, i will consider buying a new complete kit since they are less than $120. i have the older style round pads and they are almost impossible to find replacements for.
    this is such a poor design and any ideas or modifications would be greatly appreciated. has anyone who had repacked their ball bearings race have long term success with them not spilling out again?
    Last edited: Apr 19, 2009

  2. cpuaid

    cpuaid Member

    i took a digital caliper to each of the 53 balls, about 6 of them were slightly smaller than the rest. average size of balls were 2.98 - 3.00 mm. the smaller ones were 2.94 - 2.95 mm. went to the local bike shop and they suggested i move up to a slightly larger 3.16 mm diameter balls. it looks like the race will accept balls up to 3.30 mm. took apart the entire clutch assembly for a close inspection of all components. noticed that the inner race had some scoring where it should have all been smooth! the scoring was 1.5 mm high, 51.86 mm long! i never noticed it after the first repack. took a dremel tool to smooth everything all out. hopefully problem will be solved. will keep everyone posted after 100 mile road testing.

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    Last edited: Apr 20, 2009