Technique: Keeping Meidjo’s tour mode locked

Fixing the red stub bumper to keep Meidjo in tour mode.

Fixing the red stub bumper to keep Meidjo in tour mode.

One of the annoying flaws with Meidjo is the occasional tendency for the red function stub to pop over the bumper that it rests against when touring. This causes the entire spring-box assembly to be put into turn mode and will inevitably allow it to hook onto the 2nd heel of the boot. The net result is the wonderful resistance free tour mode reverts to a high-resistance free-heel mode as the spring-box hooks onto your boot and you are forced to stop and reset the red stub so the touring hook holds it down — until it pops into turn mode again without your permission.

The reason this happens is the bumper that the red stub rests against deforms under pressure changing the angle of the retaining bumper wall which then allows the red stub to pop over. Instead of being a 90° wall it relaxes to say an 88° wall when the plastic between the two ends lifts up off the ski top.

Grind the corner of the 'bumper' so it is a bit deeper.

Grind the corner of the ‘bumper’ so it is a bit deeper.


The solution is two-fold. First, deepen the corner of the bumper so that the effective angle of the bumper wall exceeds 90° to hold it down better. If you don’t have a dremmel, a good round file should do the same thing and probably provide a better margin of safety so that you don’t accidentally remove too much material. I used a ¼” diameter grinding stone in the dremmel which ground the plastic slow enough to yield good control.

Second, after the corner of the bumper is deeper, glue the entire black plastic piece to the ski top so that it cannot deform and change the angle of the bumper wall.

Glue the bumper plate down so it can't deform and change the angle of the retaining bumper.

Glue the bumper plate down so it can’t deform and change the angle of the retaining bumper.

A recent tour where I modified one intermediate plastic piece and not the other confirms these modifications cure the problem. The modified bumper held the red stub in place throughout a 3000 foot ascent on a mix of frozen white skin track pavement and wind sculpted sastrugi. The binding without the modifications popped out of tour mode at least a half dozen times.

There is little doubt making this mod could backfire if you grind too aggressively and the plastic bumper piece is severed in two. So caution is advised. You might want to order a spare first, just in case.

© 2016
 

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