I would like to reverse the gearing of my Husaberg FS 650e motorcycle so that by pressing the shifting pedal the gearbox changes up instead of down to the first gear.

There are many solutions on the market consisting of linkages that redirect the movement of the shifting pedal. Unfortunately this is not possible on my bike.

First of there is no ready to buy solution, secondly there is not enough free space around the shaft that would make this approach feasable.

So I am wondering if theoretically a mirrored/inversed shifting drum would accomplish this?

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  • $\begingroup$ Can you add a clear photo of the gearbox / gear-lever area of your bike please? Most of the ones on the googler are a bit lacking in specific detail in that area. $\endgroup$
    – user6335
    Jun 14, 2018 at 9:23
  • $\begingroup$ It's possible to find stock or aftermarket for GP-Shift for many bikes, but it seems to always be done by modifying the lever: cycleworld.com/sport-rider/… i.stack.imgur.com/FpZFX.jpg $\endgroup$
    – Rob
    Nov 12, 2022 at 18:09

1 Answer 1


To answer this question you must furnish a complete kinematic model of the entire shifter mechanism, and then study it to determine exactly how to reverse the indexing action by recutting the shifting drum.

Neither of these tasks will be straightforward.

You would be better off designing a simple 2-gear reverser mechanism which would bolt on to the shifter shaft and transmission housing, or by asking yourself just how important it really is to reverse the shifting action on that bike.

  • $\begingroup$ Thanks for replying. I am aware that engineering a special purpose shifting drum is a job of it's own. I am just wondering, if one would flatten the surface of the drum and then create a mirrored Version of it and Project it back would reverse the gearing. $\endgroup$ Jun 12, 2018 at 14:17
  • $\begingroup$ I am was thinking of the following steps: 1) use a 3D scanning technology to create a virtual copy of the orignal drum 2) mirror the surface using CAD software 3) use a metal 3D printer to create a prototype and test it. But this procedure could only work if a 1:1 mirror would create the desired effect of reversing the shifting mechanism. $\endgroup$ Jun 12, 2018 at 14:20
  • $\begingroup$ Please let us not get into a discussion about the pro & contra about reversing the gearing. $\endgroup$ Jun 12, 2018 at 14:23
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    $\begingroup$ @Matze, I think your idea of using 3D scanning and manufacture tools is feasible (and not all that expensive any more). I'd be concerned about the longevity of a Laser Sintered stainless steel part. One milled out of a billet of steel would likely be expensive but can be achieved on a 4 axis lathe/mill. $\endgroup$
    – user6335
    Jun 12, 2018 at 14:49
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    $\begingroup$ @Matze, also be cautious about how the 3 cam tracks on that cylinder are aligned with each other, it is possible that the delicate meshing requires one gear to move slightly ahead of another to avoid collisions. If this is the case then simple mirroring might not be enough to make it work properly. You might need to rotate one or two rings to be a few degrees opposite to their current position. This is actually a really interesting problem. $\endgroup$
    – user6335
    Jun 12, 2018 at 14:57

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