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Tuesday, October 2, 2012

CT70 - KO Centrifugal Clutch Build up

Time get most of this clutch built up. The manuals I have for this leave a lot to be desired. There are too many versions of centrifugal and manual clutchs on 50cc to 90cc Honda's and every manual covers all of them in unsteady and unclear detail. I also believe that the CT70K0 is a one model version too. So it took a few tries to come up with this, the pictures are a little out of chronological order, but as presented should be correct to do it right the first time. If you know more than me and spot a screw up, please let me know.

The big gear goes on the transmission input shaft.

Double check the part number on the snap ring.

Install snap ring.

How the clutch should look. ???!!!!????

This view should help more.

This gear(17) goes on the crank. The smaller gear part up.

I never disassembled parts 1, 10, 11, 13, and the screws and washers. Notice these screws are clearly marked with a dot as JIS. I had thought those didn't come onto the scene until the 80's, but actually I believe all of the screws on these Hondas are JIS.

I found eight of these little parts(23) after my first build up attempt.

I couldn't find any good explainations in any manuals, but looking at the parts diagram I think this is correct and they need go in close to the first of this build-up.

This is 16, 4, and 22. I didn't take these apart so I shouldn't need a new snap ring.

That assembly lays right in here.(The rollers(23) should still be here in this picture, too.)

The steel plate with the fingers(7) goes on next.(The rollers(23) should still be here in this picture, too.)

riction plate(6). These aren't great, but runnable for now.

Steel plate with knotched ears(9).

Another friction plate(6).

Four new springs(12), because I lost one tearing it down.

Springs(12) go onto the fingers of 7.

Steel with holes(8). This piece is not pretty but runnable.

Retaining ring(14) holds it together.

Flip it over and put it on the crank.That's a good stopping point for today.


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