Bicycles, why so confusing?

[minimutly]

I just (jokingly) had a go at my 9 yr old grandson for not removing the new pedals off his previous bike that's soon for the scrapyard. As part of the discussion I tried to get him to think about which one would be rh, and which one lh thread. Blank looks came back, so we went out and I showed him on my Dawes what happens if a bearing in the pedal were to go tight, and why it would unscrew if normal thread.
So to prove the point I got a spanner and proceeded to unscrew the rh pedal. Except I didn't, it tightened. And the opposite one the same. Why?
To rub salt in the wound one of the pedals was a bit tight so I took it off to clean and adjust, this is when I dropped one of the balls in the mess on my workshop floor. So 3 hours later the pedal is back on minus one ball, but the workshop floor is clean. AND, further to that, grandson has had a snoop around and counted all my Yamahas, shock horror, I have 8 bikes apparently. Won't be long before the little cherub tells his grandma...

 

[Misterg]

So to prove the point I got a spanner and proceeded to unscrew the rh pedal. Except I didn't, it tightened. And the opposite one the same. Why?

In a word: precession.

i.e. If you waggle something in a circular fashion (apply a force whose direction is constantly changing), that something has a tendency to rotate in the opposite direction to the waggle.

Left hand pedal is left hand thread is the way I remember it. It's opposite to the bottom bracket adjusters (if anything still has those any more).

 

[sparkysy]

Did similar yesterday but with my compressor.
Had my 7yo helping me and she said the oil looked low on the compressor! Well spotted as I hadn't noticed, so proceeded to top it up explaining why that was a good spot and how important it was to use the right grade and put exactly the right amount in.
Having topped it up and run it for a bit, it smelled warm and was, this was when I realized I had used the wrong grade for that compressor
Then spent an hour removing the oil and putting the correct grade in! Again explaining the importance of using the right stuff!!

 

[Morrisman]

In a word: precession.

i.e. If you waggle something in a circular fashion (apply a force whose direction is constantly changing), that something has a tendency to rotate in the opposite direction to the waggle.

Left hand pedal is left hand thread is the way I remember it. It's opposite to the bottom bracket adjusters (if anything still has those any more).

I swapped out the pedals on my sisters sports cycle last week, she had new ones to go on, labelled left and right. Which was good, because I knew one side was left hand thread, I just couldn’t remember which side. And no thread was showing for me to see.

They were tight as hell, but a bit of leverage on the Allen key had them both come loose with a loud crack.

 

[minimutly]

Yeah, I was lucky cos I felt the rh one move then stop - otherwise I would have been tightening it up!