Sam I just checked by trusty box of goodies and I have a cycle X 520 offset sprocket to adapt the early K motors to the F or late K frames / swing arms.
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I would appreciate some forum help on something though,
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When I started planning the project I had a few early K gearboxes.
I purchased the undercut gears from Cycle X, then started to look at tightening up the 4th and 5th gear ratio's I wanted to tighten those two ratio's up nice and close.
The easiest option was to buy the Nova gears and they were approx $400. each.
Then I looked at the early K 4th gear and the F or late K 5th gear and it was pretty close to what I want so I emailed Jim at Cycle X and asked this question..........will the 5th gear ratios of the later gearbox fit on the early shafts ? or can I swap out gears to make it work ?
Jim wasnt sure , so before I buy a used F or later gear cluster of ebay and see if it can be done ?
Has anyone had a play with early and late gears together
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Fingers crossed..........johno