Cheap Bike Pedal Disassembly and Postmortem

Late last year, I bought a pair of inexpensive bicycle pedals from a large, relatively well-respected online bike store. They were mid-sized lightweight no-name things made in China, and they were, as I mentioned, cheap.

Fast forward to this spring – a few hundred miles of riding later – and I’m cleaning the bike one day when I notice that the pedals really don’t want to turn. Like, very substantial force is required to make them rotate. I also note that the alloy parts of the pedals are horribly bent and twisted (which I’d noticed before), and that the plastic core of the body on each is bent and distorted, in one case so much that the dust cap on the end has come off (which I hadn’t noticed).

Okay, they were cheap, in every sense of the word. Lesson learned, I bought some decent pedals and replaced them, and have been much happier. In fact, the old ones were so stiff, my speed on that bicycle, all other things being equal, increased just under 20%.

Crazy.

Anyway, I was curious as to just how the pedals had turned to suck, so I finally got around to disassembling them and conducting a postmortem of sorts. Here’s the report, as it were:

Here’s the subject of today’s examination – a less-than-one-year-old left pedal, black in color. It exhibits the typical wear and tear of a cheap pedal subjected to a few hundred miles of urban commuting.

Removal of four screws allows us our first glimpse at the subjects innards, and it’s not a pretty sight.

Removal of a nut and two washers permitted access to the outer bearing cone, which was unthreaded from the axle. This revealed some horrible-looking bearings in an even more horrible-looking bearing cup, and a large volume of a thick tar-like adhesive substance that, while probably being at least theoretically grease, was in completely useless positions.

The outer bearing cone was examined and found to look horrible.

The cup and cone were subjected to environmentally-unfriendly degreaser, cleaned, and examined. Alleged grease was determined to have a consistency and composition comparable to cockapoo excrement. Cone displayed moderate wear, including some pitting. Stamped metal cup displayed considerable wear and severe pitting. Ball bearings were found to be obviously non-round.

Basically, in a nutshell, it’s a badly-made pedal assembled with a really horrible excuse for grease. I thought maybe it was unfair to only look at the outer bearings on this pedal, exposed somewhat due to the loss of the dust cap, but the inner bearings were just as bad if not actually worse, and the other pedal – which had retained its dust cap – was pretty much identical.

I probably only rode three or four hundred miles on those pedals, between maybe late August and late October, and maybe late March to early April. They weren’t exposed to rain or snow or anything. (I’m a fair-weather cyclist.) They died because they’re badly-made of cheap materials, and assembled with some ludicrously shoddy alleged grease. Horrible grease seems to be really common on el-cheapo bicycle parts; you’d think by now the people making these things would realize it sucks, but I guess they just don’t care. Even if they’d used better grease, though, the pedal body is weak, the aluminum part is flimsy, and the attachment between the two doomed to failure.

Moral of the story: Don’t buy cheap bike pedals.

Published in: Geekiness, General | on July 1st, 2011| 3 Comments »

Both comments and pings are currently closed.

3 Comments

  1. On 7/19/2011 at 11:01 am Nemo Said:

    The “weird lines” on the alloy part of the pedal in a couple of the pictures aren’t cracks, they’re the edges of pieces of black adhesive reflective tape I applied there for increased visibility. Not sure how much they helped, if at all, but nobody’s run me over while biking at night, so…

  2. On 9/22/2011 at 7:59 pm James Mckintosh Said:

    They look horrible. Now i’m having second thought of buying cheap pedals…

  3. On 3/4/2017 at 10:23 pm brucey Said:

    my two pence worth;

    1) if you tend to be rough with your pedals, it probably isn’t a good idea to buy ones with plastic bodies; they tend to cause all kinds of problems.

    2) that said, the damage to your pedals (bent cages) suggests that almost any pedal you have might well break in your use.

    3) Fundamentally, pedals with (similar, angular contact) bearings that are symmetrically disposed about the centre of your foot are a better idea; it doesn’t really matter if the bearings are close to one another or not, just so long as they are symmetrically disposed. A short spindle with one bearing under the middle of your foot is a bad arrangement, because the balls will scuff in that bearing (which is probably why the cup is so worn in your pics).

    4) cheap pedals with no seals need adjustment and lubrication; plastic pedal bodies are often too flexy to allow the adjustment to be accurate.

    5) cheap pedal bearings of this sort are actually much better than you might expect for the price. The (CrMo) spindles hardly ever break and the bearings can last well if they are symmetrically disposed, adjusted and lubricated correctly. If (say) you buy Wellgo LU987 pedals, they come with similar (but more symmetrically disposed) bearings inside, but such pedals can last for years with just a little TLC.

    6. If you tend to break your pedals (any pedal can be bent or broken in a prang) there is arguably no point in spending a lot of money on them.

    BTW The inboard bearing in unsealed pedals can easily be lubricated by using a little spray lube of the sort that is used on motorcycle chains.

    cheers