In absence of a vice, position the crank arm on a curb so that when undoing the pedal the crank arm will push into the curb. Wrap in a towel if you are bothered about scratching the arm. Then use friend to brace the bike. Apply quality allen bit attached to large ratchet wrench. Success!
In absence of a vice, position the crank arm on a curb so that when undoing the pedal the crank arm will push into the curb. Wrap in a towel if you are bothered about scratching the arm. Then use friend to brace the bike. Apply quality allen bit attached to large ratchet wrench. Success!