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  1. #1
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    Oil+Oxygen+Pressure = Diesel

    So, after accidently releasing too much Nitrogen from my Manitou Metel R Shock in an attempt to improve the performance, the forum and thread searching mayhem has begun.

    Just to make sure, we are talking about Coil Shocks here.

    I've seen people say that you can reinflate your shock back up with a shock pump or anything that goes up to 200 psi. I don't see the problem as long as you have a shrader valve or a hypodermic needle, but a greater fact concerns me.

    At high pressures, oil and oxygen bond to form diesel, and after diesel is formed, under high compression ignition may occur and boom; Bye bye shock, and bye bye bike and most likely your manhood.

    Shocks are standerly filled with N2, inorder to prevent oil cavitation inside.

    So to get to the point: If a shock is reinflated with oxygen, could the pressure inside cause diesel to form and inginte?!?!

  2. #2
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    I highly doubt this scenario. :screwy:

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  3. #3
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    Quote Originally Posted by Meek Meek Meek View Post
    So, after accidently releasing too much Nitrogen from my Manitou Metel R Shock in an attempt to improve the performance, the forum and thread searching mayhem has begun.

    Just to make sure, we are talking about Coil Shocks here.

    I've seen people say that you can reinflate your shock back up with a shock pump or anything that goes up to 200 psi. I don't see the problem as long as you have a shrader valve or a hypodermic needle, but a greater fact concerns me.

    At high pressures, oil and oxygen bond to form diesel, and after diesel is formed, under high compression ignition may occur and boom; Bye bye shock, and bye bye bike and most likely your manhood.

    Shocks are standerly filled with N2, inorder to prevent oil cavitation inside.

    So to get to the point: If a shock is reinflated with oxygen, could the pressure inside cause diesel to form and inginte?!?!
    That's some high compression!

    must. .drop ..bombs

    where can I buy this diesel shock (awesome name)

    *joking, hope you get your shock sorted
    Last edited by Deerhill; 03-19-2012 at 07:47 PM.

  4. #4
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    Lol, my question was if it is possible for this to happen due to the pressures inside the shock itself.

  5. #5
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    Sounds pretty unlikely. However to have fire, you must have 3 things, fuel (oil) heat source (friction) and oxygen, so technically you've got all three. As for the diesel, I'll leave that to the hydrocarbon engineers out there.

    ?? Could you not just have it re-charged with nitrogen?
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  6. #6
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    I'ts to complicated and time consuming to fix my current shock as my rebound knob is broken (snapped off) at the moment. Gonna buy a 2005 4-Way for $44 and possibly siamese it later with the metel r.

  7. #7
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    Quote Originally Posted by Meek Meek Meek View Post
    So to get to the point: If a shock is reinflated with oxygen, could the pressure inside cause diesel to form and inginte?!?!
    A MTB shock never gets anywhere near hot enough to ignite the oil in it (unless you pump it up to 500psi and attach a glow plug, in which case... erm...).

    With your new Swinger, look at sending to Avalanche for their revalve service, they replace the SPV with a normal compression shim stack, makes for a really nice shock (as good as current high end units) for less than $200.

  8. #8
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    Quote Originally Posted by Fix the Spade View Post
    A MTB shock never gets anywhere near hot enough to ignite the oil in it (unless you pump it up to 500psi and attach a glow plug, in which case... erm...).

    With your new Swinger, look at sending to Avalanche for their revalve service, they replace the SPV with a normal compression shim stack, makes for a really nice shock (as good as current high end units) for less than $200.
    I think that was his intention to DIY, by cannibalizing the Metel for the piston, no?

    Some time ago, it was quite common to replace the SPV piston like that.


    Magura

  9. #9
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    Quote Originally Posted by Meek Meek Meek View Post
    So, after accidently releasing too much Nitrogen from my Manitou Metel R Shock in an attempt to improve the performance, the forum and thread searching mayhem has begun.

    Just to make sure, we are talking about Coil Shocks here.

    I've seen people say that you can reinflate your shock back up with a shock pump or anything that goes up to 200 psi. I don't see the problem as long as you have a shrader valve or a hypodermic needle, but a greater fact concerns me.

    At high pressures, oil and oxygen bond to form diesel, and after diesel is formed, under high compression ignition may occur and boom; Bye bye shock, and bye bye bike and most likely your manhood.

    Shocks are standerly filled with N2, inorder to prevent oil cavitation inside.

    So to get to the point: If a shock is reinflated with oxygen, could the pressure inside cause diesel to form and inginte?!?!

    Not really an issue, as one of the reasons you can make things go boom, is the fumes, not the liquid itself.
    The grand reason to use N2, is to get the thermal expansion level down.
    That again is also hardly an issue, so no need to worry.


    Magura

  10. #10
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    Well yeah more or less DIY. I'm looking at a 2005 Swinger 4-Way for $44 and eventualy probably replace the piston with the Metel. Manitou contacted me after an email I sent and they said that the oil and the gas whether it is N2 or Oxygen is seperated from the oil by an IFP.

  11. #11
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    Quote Originally Posted by Meek Meek Meek View Post
    Lol, my question was if it is possible for this to happen due to the pressures inside the shock itself.
    No it can't and won't happen for a lot reasons.

  12. #12
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    Quote Originally Posted by Meek Meek Meek View Post
    At high pressures, oil and oxygen bond to form diesel, and after diesel is formed, under high compression ignition may occur and boom;

    Shocks are standerly filled with N2, inorder to prevent oil cavitation inside.

    So to get to the point: If a shock is reinflated with oxygen, could the pressure inside cause diesel to form and inginte?!?!
    Diesel is not formed from oil and oxygen.......

    it is a hydrocarbon closely related to kerosene, heating oil, and jet fuel.

    it consists of hydrogen and carbon.

    Shocks are filled with nitrogen to prevent corrosion from the water vapor in air, and oxidation from the oxygen in the air.

    any pressurized gas helps to prevent cavitation, not just N2.

    no, your shock will not blow up, it doesnt get hot enough for combustion

    they do get plenty hot though, I burnt my hand on the shock of a motocrosser once.

    Drew
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    If it COULD happen, you'd have heard about it happening. Never heard of such so it's extremely remote, at best.
    Not enough O2 for it to happen. Diesel engines us a LOT of air. And in the case of our VW cars.....very little diesel fuel
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  14. #14
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    If it was so easy to make diesel, then why do we have to pay >$4 a gallon? This scenario would have to get very very hot in order for it to happen, no chance.
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  15. #15
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    Hmm, I see great responses everyone. Just wanted to know as I was probably going to fix my Manitou Metel R, but it would cost more and take more time than buying a 2005 Swinger 4-Way, which I am going to get lol.

    Might eventually siamese the two.

    Also, you say it doesnt get hot enough, cant it still explode under the pressure? Or no?

  16. #16
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    Quote Originally Posted by Meek Meek Meek View Post
    Hmm, I see great responses everyone. Just wanted to know as I was probably going to fix my Manitou Metel R, but it would cost more and take more time than buying a 2005 Swinger 4-Way, which I am going to get lol.

    Might eventually siamese the two.

    Also, you say it doesnt get hot enough, cant it still explode under the pressure? Or no?
    Put the Metel piston into the Swinger 4 way, and you have a pretty hefty shock.

    I made a similar conversion with a 6 way, now that just kicks butt!

    As for the anticipated explosion......Make sure you get it on video

    Now having played around with engines for some years, I can assure you that making diesel explode, takes some rather unique circumstances, and that's not gonna happen in the air chamber of a shock, not even yours



    Magura

  17. #17
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    Quote Originally Posted by Meek Meek Meek View Post
    .............Also, you say it doesnt get hot enough, cant it still explode under the pressure? Or no?
    If you put this question in the context of a diesel engine it will make more sense to you. Diesels are indeed compression ignition engines, but the combustion chamber and process are entirely different than your shock.

    In a diesel engine, the air is drawn into the cylinder and compressed by the piston coming up. Compression ratios are typically somewhere around 20 to 1, and the pressure in the cylinder is often 500 to 600 psi depending on the engine. The compression stroke happens extremely fast and as a result of the speed and pressure, a great deal of heat is generated.

    When the pressure and heat are at the maximum, a relatively small amount of fuel is injected into the chamber. The fuel is injected through a nozzle that is specially made to atomize the fuel, essentially it enters the chamber as a mist. The air to fuel ratio in the chamber is typically something like 15 to 25 parts of air to one part of fuel.

    With those conditions met, it is the perfect environment for the fuel to ignite.

    Compare that to your shock. The speed and pressure of compression is no where near high enough to get the heat necessary. The oil is not an ideal fuel, it is already in the chamber, it is not being atomized in any way that would make it easy to ignite, and it is not in a correct ratio with the air to achieve optimum conditions to ignite or burn.

    Basically, no, your shock will not explode. And BTW, that is not how diesel fuel is made.
    I'm not very smart, but I can lift heavy things

  18. #18
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    Quote Originally Posted by muzikym View Post
    If it was so easy to make diesel, then why do we have to pay >$4 a gallon? This scenario would have to get very very hot in order for it to happen, no chance.
    OK you asked:
    You wanted "Clean Air", you got it! The EPA requires all sorts of crap for diesel fuel now. Low sulfur, etc. Also, they required scrubbers in the exhaust system, which causes.....yup.....WORSE mileage. Well, that sure makes sense. Plus, they WANT diesel cars to get worse mileage, so it props up the gas/hybrid bull crap. Our VW diesels average 42 mpg, driving around town. Around 46-50 highway. Could be BETTER with better fuel and without the "clean air" crap on the car. Also they LIMIT diesel engine sales, based on a percentage of gas cars sold. This is why you never see VW advertise their diesel cars, even though you can get upwards of 50 mpg. They are gonna sell everyone they import because of the EPA bull crap limits on sales. Stupid ****!!
    You asked.
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  19. #19
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    If there were anything wrong at all with pumping plain air into shocks (let alone some outlandish risk like that of an explosion!), can you imagine any shock manufacturer giving out shock pumps to go along with their shocks? Yet, they routinely do.
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  20. #20
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    Thanks for the replies. Don't hate I'm only 15 rofl. Well, I asked Manitou service about it and they said that the oil and N2 are in seperate chambers, which are divided by an IFP. They also said they don't use oxygen as it expands when heated (I already knew that) and that any other gas that doesnt have this property could work.

  21. #21
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    Quote Originally Posted by Meek Meek Meek View Post
    They also said they don't use oxygen as it expands when heated (I already knew that) and that any other gas that doesnt have this property could work.
    Your wording seems to imply that using gases that don't expand when heated is considered okay. If that's what you mean (or what the Manitou people mean), then you shouldn't have difficulty in taking this as a little bit of education, since you're 15: All gases expand when heated. Not only that, but they all expand by the same amount when heated. (Take a look here, and read the section titled "The Gas Law" about halfway down the page.)
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  22. #22
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    Quote Originally Posted by erginguney View Post
    Your wording seems to imply that using gases that don't expand when heated is considered okay. If that's what you mean (or what the Manitou people mean), then you shouldn't have difficulty in taking this as a little bit of education, since you're 15: All gases expand when heated. Not only that, but they all expand by the same amount when heated. (Take a look here, and read the section titled "The Gas Law" about halfway down the page.)
    Thanks for the link.

    Nice and easily understandable info.


    Magura

  23. #23
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    Good job! cool link

    Quote:
    Originally Posted by erginguney
    Your wording seems to imply that using gases that don't expand when heated is considered okay. If that's what you mean (or what the Manitou people mean), then you shouldn't have difficulty in taking this as a little bit of education, since you're 15: All gases expand when heated. Not only that, but they all expand by the same amount when heated. (Take a look here, and read the section titled "The Gas Law" about halfway down the page.)

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  24. #24
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    Hmm, I really don't know what he meant. I knew that all gases expand it's just at different rates.

    This is what the Manitou Service replied with: Oxygen can/will expand when hot. N2 will not expand under heat.

    So using N2 will keep the shock feeling the same weather it is hot or cold.

    Well, generally from what i have learned, I'm guessing that other gasses won't expand as much as oxygen under the heat produced from pressure/compression of the shock.

  25. #25
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    No my friend, they don't act differently, the Manitou guy doesn't know what he's talking about. The ideal gas law states that all gasses act the same under identical conditions of temp, pressure, and volume. They use N2 because it is relatively inert chemically. Air has oxygen in it, and water vapor too, which are bad for the internals of the shock. N2 is a better choice.

    Drew
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