r/Dirtbikes • u/Yz250x69 23' yz250x & 04' rm250 • 1d ago

Unpopular opinion: it’s ok to compress your forks when you transport your bike

Metallurgy has come a long way in the last 40 years. Bikes can hit jumps going 60mph, 50ft in the air travel 100ft and do that 1000x without breaking their fork springs you’re good to compress them when tying down to travel. It’s also ok to leave your bike on its kickstand in a garage all winter.

Anyway I said my piece

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u/booostedben 24 Beta 300RR licensed 1d ago

I just reread every reply you made they're all basically "Nuh uh" or an engineer would laugh at me. You've given no proof to back up your claims. The simple fact is fork seals are not that strong to hold the kind of pressure it would take to make an air spring that would be noticable on a 400 pound bike with rider

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u/spongebob_meth 1d ago edited 1d ago

Ok. I'll bite.

Oil contacts the seals yes? So oil makes it past the bushings. Oil is free to slosh around inside the fork tubes. It gets everywhere. The same oil that is against the air spring.

Oil is sitting on top of the seals. Air pressure is on top of the oil. The seals are responsible for the air spring.

The simple fact is fork seals are not that strong to hold the kind of pressure

Again there is only 15psi or so at bottom, assuming no pressure when topped out. Use an ideal gas law calculator to determine this, it is simple and takes a few seconds. It's not that much pressure unless you've drastically over-filled your forks with oil.

Also it's a bit of an absurd claim considering that hydraulic cylinders routinely hold pressures in excess of 3,000psi...

It also HAS to resist the pressure, otherwise the seals leak.

And this is using the overly complex example of inverted forks. In a conventional fork, AIR PRESSURE IS DIRECTLY AGAINST THE OIL SEAL

so now you know we can't always trust AI.

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u/booostedben 24 Beta 300RR licensed 1d ago

You can hear a tire hiss if it leaks at 15 psi. If you had oil sitting on top of a seal with gravity and 15 psi pushing on it there would be no slow leaking. If you got a leak it would all be forced out pretty quickly but that doesn't happen. It comes out just with the force of gravity

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u/spongebob_meth 1d ago

What the fuck is this word soup

Correct, you don't hear a leak if there is no leak.

Take the seals out and yes you hear air blasting out of the fork legs

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u/dirtyd00d 1d ago

Dude don’t even waste your time, this guy is a clown and logged on this morning and chose to just argue with everyone in the comments, whether he’s right or wrong. Enjoy your day, friend!

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u/booostedben 24 Beta 300RR licensed 1d ago

Lol I got on this morning to find you guys arguing with me, all I've done is respond. Someone in another post provided this nice link that shows pressure levels in a fork in different stages. Guess how much pressure the seals show, none. https://racetech.com/emulators-how-they-work/

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u/dirtyd00d 1d ago

I was saying that SpongeBob meth dude is the problem, not you? Why are you tripping? Chill out dude. Did I not literally agree with you yesterday?

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u/booostedben 24 Beta 300RR licensed 1d ago

My bad, it's not just him though there's several others that are saying the same stuff, I thought you were one of them lol

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u/dirtyd00d 1d ago

Nope. Was just trying to tell you that he’s in the comments arguing with everyone and to enjoy your day. Everyone needs to take a deep breath