Tightening a pedal to correct torque

rumbataz
rumbataz Posts: 796
edited April 2018 in Workshop
So I've installed my new pedals and tightened them with the basic Park Tools 8mm hex key. The key isn't huge like the Park Tools 15mm spanner so you can only exert a fairly small amount of force. I cannot use the spanner on the new pedals.

Anyway, whilst browsing the Shimano user and dealer manuals, I noticed that the pedals need to be tightened to something like 40Nm. That's really tight and simply not possible to achieve with the 8mm hex key.

How do people on here tighten pedals using just a hex key to ththe required torque? Or don't you bother and just tighten them as best you can?

Comments

  • qube
    qube Posts: 1,899
    You could pick up an 8mm hex ratchet adapter somewhere. If you already have a torque wrench.

    Grease the threads first before assembly.... Correct torque is fairly important too.

    Torquing a bolt stretches it and locks it into the threads.
  • 964cup
    964cup Posts: 1,362
    I've never understood why people want to torque pedals to death - it just makes it harder to remove them. I doubt I've ever tightened a pedal beyond 10-12nm at most, and I've never had a pedal come loose or otherwise misbehave. The whole point of the handed threads on pedals is so that their tendency is to self-tighten.
  • arlowood
    arlowood Posts: 2,561
    I've never understood why people want to torque pedals to death - it just makes it harder to remove them. I doubt I've ever tightened a pedal beyond 10-12nm at most, and I've never had a pedal come loose or otherwise misbehave. The whole point of the handed threads on pedals is so that their tendency is to self-tighten.


    ^^ +1 In over 30 years of cycling I've never used a torque wrench on pedals. An 8mm hex key with about 6 inches of leverage is all I've ever needed. Never had a pedal come loose

    Good luck with torquing to 40Nm. Pedals are one of the most problematic components with respect to siezing so I don't think they need any help by applying a massive torque.
  • keezx
    keezx Posts: 1,322
    I've never understood why people want to torque pedals to death - it just makes it harder to remove them. I doubt I've ever tightened a pedal beyond 10-12nm at most, and I've never had a pedal come loose or otherwise misbehave. The whole point of the handed threads on pedals is so that their tendency is to self-tighten.

    +2 , a torque wrech is 100% useless for pedals.
    Never buy pedals without 15 mm flats, you can torque them but after 2 years the'll not come loose with a hex wrench.
  • Okay thanks all. I'll leave them as they are.
  • grenw
    grenw Posts: 803
    I've never even bothered with more than a cursory tighten with a normal 8mm hex key. They screw on in 2 different directions for a reason - so that the pedaling action, if anything, will tighten them.

    A bit of grease and a quick tweak and that's all.
  • svetty
    svetty Posts: 1,904
    I never tighten pedals much more than finger tight and use plenty of grease. I frequently travel with my bike(s) and often remove and re-fit pedals. No need to crank them up and risk seizing...
    FFS! Harden up and grow a pair :D
  • I never tighten pedals much more than finger tight and use plenty of grease. I frequently travel with my bike(s) and often remove and re-fit pedals. No need to crank them up and risk seizing...
    ^^ This.

    Finger tight, with grease. Just takes a light tap with a mallet on the end of an open spanner to start it unscrewing. As others have said, pedalling keeps it done up.
    Is the gorilla tired yet?
  • 964cup
    964cup Posts: 1,362
    Should add that my 10-12nm was based on feel using a Park Tool pedal spanner, not a torque wrench. I've also never struggled to get my own pedals off; had some fun with other people's, though. Grease and clean threads are key.
  • sheffsimon
    sheffsimon Posts: 1,282
    So I've installed my new pedals and tightened them with the basic Park Tools 8mm hex key. The key isn't huge like the Park Tools 15mm spanner so you can only exert a fairly small amount of force. I cannot use the spanner on the new pedals.

    Anyway, whilst browsing the Shimano user and dealer manuals, I noticed that the pedals need to be tightened to something like 40Nm. That's really tight and simply not possible to achieve with the 8mm hex key.

    How do people on here tighten pedals using just a hex key to ththe required torque? Or don't you bother and just tighten them as best you can?

    I've never used a torque wrench on anything on a bike, and never had something fall off or crushed anything. It's just a bike.

    I don't recall ever seeing any torque settings for nuts and bolts on bikes in the 80's and 90's and we managed perfectly well.....

    Pedals just need a slight nip with an allen key, bit of grease on the threads, as said further up.
  • sungod
    sungod Posts: 16,497
    you apply antiseize the the threads then tighten them by feel to nnghh torque

    if you do it to NNNNNNGHHHHH torque that's too tight and they'll be much harder to remove
    my bike - faster than god's and twice as shiny
  • 964cup
    964cup Posts: 1,362
    I don't recall ever seeing any torque settings for nuts and bolts on bikes in the 80's and 90's and we managed perfectly well.....
    With just the minor difference that we didn't have carbon frames or components in the 80s and 90s. I'm religious about using a torque wrench on carbon: the stem bolts on one of my bikes are rated to 4nm; which really isn't very much at all; it wouldn't be hard to ruin it by over-torquing. Same for lightweight seatposts and so on. By the same token, I use a torque wrench for fitting chainsets, because judging 45nm by feel is hard, and under-tightening them has tedious consequences. BTDTHMCFO.
  • Yep agree with all those saying not to tighten too much. This morning after much faffing around I finally managed to remove drive side pedal, it was really tight. So, now reinstalled with anti-seize and only pinched up by hand with small length allen key.
  • ayjaycee
    ayjaycee Posts: 1,277
    When working on a carbon bike, I tend to use a torque wrench everywhere except on pedals (although others will say you don't need the torque wrench and should just use The Force). Unless your Walter The Softy, the tightest that you can manage just using the 8mm hex is probably too tight. Don't forget the grease.
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