Pedal power

pedal-wood-03-pair File this one under “first-world prob­lems.” Since putting togeth­er my belt-dri­ve city bike last fall, I have been look­ing for a bet­ter way to ride (occa­sion­al­ly) with nice leather-soled shoes. Every met­al- and plas­tic-sur­faced ped­al I tried rubbed uneven­ly against the shoe, destruc­tive­ly dug into the leather sole with sharp points, or both.

The solu­tion seemed to come in the form of the Moto Urban Ped­al, which has an unusu­al­ly large flat fric­tion sur­face as well as a dis­tinc­tive ply­wood body. Unfor­tu­nate­ly, the fric­tion is pro­vid­ed by “strong grip tape.” While their adver­tised claim is true–that the skate­board-style grip tape pro­vides slip-free con­tact even with wet leather soles–the man­u­fac­tur­er doesn’t men­tion that grip tape also destroys leather by grind­ing it down. As I found out, grip tape is just coarse sand­pa­per with an adhe­sive back­ing. That solu­tion is per­fect for the skate­board-indus­tri­al com­plex because it ensures a steady cycle of demand for new skate­board­ing shoes, but it is unsuit­able for my needs.

So I began my Edi­son-style exper­i­ment with every kind of fric­tion mate­r­i­al I could get my hands on. I tried sev­er­al dif­fer­ent mod­els of 3M Grip­ping Mate­r­i­al, the amaz­ing stuff that sim­u­lates gecko feet, but it quick­ly became clogged with debris. I tried a tex­tured self-adhe­sive neo­prene prod­uct designed for guns (?!), but it lacked the dura­bil­i­ty and adhe­sive strength I need­ed.

Final­ly, Feld­meier sug­gest­ed that the best fric­tion mate­r­i­al for shoes might be anoth­er shoe. From an online cob­bler sup­pli­er, I obtained two sheets of sol­ing mate­r­i­al: a 2 mm SoleTech sol­ing sheet for dress shoes and a 4 mm sheet of Vibram 7175 boot rub­ber. The Vibram mate­r­i­al is amaz­ing but way too thick and heavy for this appli­ca­tion, so I put it aside. The SoleTech (check-tex­tured SBR rub­ber) is per­fect.

I made a tem­plate of laser-cut acrylic so I could cut per­fect ped­al-shaped pieces from the sheet with a knife.

2014-09-14 11.19.01

Rub­ber con­tact cement pro­vides a per­fect (although pos­si­bly too per­ma­nent) bond to the plas­tic pieces that form the plain bear­ings in the Moto ped­als. It also smells awe­some.

2014-09-14 11.41.37

The new ped­al sur­faces are work­ing great so far, wet and dry. And they don’t destroy leather. We’ll see how they hold up in the long term.

2014-09-15 09.13.14

Leave a comment

Leave a Comment

September 18, 2014 September 18, 2014 cycling by Scott [permanent link]