Miata Turbo Forum - Boost cars, acquire cats.

Miata Turbo Forum - Boost cars, acquire cats. (https://www.miataturbo.net/)
-   Suspension, Brakes, Drivetrain (https://www.miataturbo.net/suspension-brakes-drivetrain-49/)
-   -   tracking bilsteins with no oil (https://www.miataturbo.net/suspension-brakes-drivetrain-49/tracking-bilsteins-no-oil-58836/)

orion4096 07-02-2011 05:45 PM

tracking bilsteins with no oil
 
Hypothetically speaking, if you had rear bilsteins that lost all their oil how would the car handle at the track? I assume they would provide minimal damping, but would this cause the car to push?

Is it possible that the internals of the shock are damaged if most of the oil leaked out?

hustler 07-02-2011 05:55 PM

um...if there is no oil there is no damping.

falcon 07-02-2011 06:21 PM

lol

Are you asking on a hypothetical basis? Or did you track your car with no oil and didn't find out until after?

wannafbody 07-02-2011 09:07 PM

Without oil wouldn't it be an air shock?

orion4096 07-02-2011 09:20 PM

Ya, it's not actually hypothetical. I just pulled the shocks off my car and found the rears were swapped. The control arms hit this valve that was added near the base when they were setup. Looking closer, it doesn't appear to be for oil (which probably means my diff is leaking), but for the gas under the piston (I think?). However, I'm not certain what it would do to the cars handling to have little to no damping in the rear. I figured this may be another contributor to my understeer problem, but less grip in the rear usually means the car oversteers.

Rennkafer 07-03-2011 12:45 PM

Mike, if the schrader valves are knocked off than at the least you lost the gas charge(which on Bilsteins is fairly high pressure), which could tend to make the car understeer more.

If they're FCM's work, take them back to him and have them repaired and then put them on the correct sides so the valves don't get knocked off again. Try driving the car again and see if the problem is still there. I wouldn't start any plans to change/upgrade stuff until after I'd done the (relatively) cheap, easy solution.

Thucydides 07-03-2011 03:10 PM

This, among other reasons, is why you don't want Schrader valves on your Bilsteins. When you loose your gas charge the shock fluid cavitates and foams, and your damping goes away. You essentially don't have rear shocks at this point, and need to correct that problem before you can begin to sort your handling issues. The cavitation can also destroy internal parts by erosion, but that's a secondary issue.

Rennkafer 07-04-2011 02:45 AM

Schrader valves themselves aren't an issue if the shocks are properly installed.

Get em fixed and try them... no reason not to.

wannafbody 07-04-2011 09:28 AM


Originally Posted by Rennkafer (Post 744686)
Schrader valves themselves aren't an issue if the shocks are properly installed.

Get em fixed and try them... no reason not to.

Schrader valves have been known to leak.

hustler 07-04-2011 09:46 AM

AST/XIDA valves sit almost flush.
http://949racing.com/ProductImages/9...ing_XIDA_S.jpg

Rennkafer 07-04-2011 12:56 PM


Originally Posted by wannafbody (Post 744702)
Schrader valves have been known to leak.

Bilstein has been using Schrader valves on race shocks for 40 years +... pretty much every gas charged race shock comes with a valve of one sort or another on it (including AST/Xidas as Hustler pointed out).

We could waste lots of time going "what if"... to no end at all. If the shock bodies aren't damaged, there's no reason not to replace the valves, check the oil fill and recharge the gas. Then Mike can run them and see if he likes them, if not he's got functional shocks to sell and make up part of the cost of better pieces. What he has right now are two large paperweights.

Rennkafer 07-04-2011 01:04 PM


Originally Posted by hustler (Post 744703)

Looking at them, it appears they stick out less than the regular Schraders but not a ton less. The Schraders on my Bilsteins aren't like a tire valve stem that stick out an inch.

And I'll reiterate... INSTALLED PROPERLY they don't hit anything and have no problems. Mine have been on over two years with no issues, Mikes are the first I've heard of having an issue and he said they were improperly installed.

You guys are focusing on the Schrader valve being an issue when it was the installation that caused the problem... :facepalm:

Thucydides 07-04-2011 01:12 PM

Not focusing, just saying.

There's a difference between a Schrader valve installed at the factory, and another installed as a work-around. I wouldn't worry about the valves on the Xida's either, as the shocks were designed with them in mind originally, and the quality of the valves are likely of the same high standard as the shocks.

Were are the valves coming from when they weren't installed at the factory? USA, Germany, China, Malaysia? The Schrader valves that they installed on my stock wheels at Big-O aren't of the same quality that came on my Enkei's.

Schrader valves have been know to leak, and from a variety of reasons including road debris, heat, and just a bad valve. An external valve on a non-adjustable Bilstein is unnecessary, and a shock built without an exposed valve has one less failure point. Simple.

But back to these shocks. You have to take the shocks off to repair them anyway, so I would certainly replace the fluid as it's been compromised by cavitation. That means opening the shocks. While you're in there you might as well have a look at the valve shims, as they take a beating from cavitation too. None of this is particularly expensive, and you'll know at least that part of your suspension is right.

Thucydides 07-04-2011 02:10 PM

Are the valves on the Xida's even Schraders? If so, they look as though they're shielded against debris. Might be a useful upgrade for Shaikh to consider if it's more than just a cosmetic improvement.

Rennkafer 07-04-2011 06:25 PM


Originally Posted by Thucydides (Post 744749)
Not focusing, just saying.

There's a difference between a Schrader valve installed at the factory, and another installed as a work-around. I wouldn't worry about the valves on the Xida's either, as the shocks were designed with them in mind originally, and the quality of the valves are likely of the same high standard as the shocks.

Were are the valves coming from when they weren't installed at the factory? USA, Germany, China, Malaysia? The Schrader valves that they installed on my stock wheels at Big-O aren't of the same quality that came on my Enkei's.

Schrader valves have been know to leak, and from a variety of reasons including road debris, heat, and just a bad valve. An external valve on a non-adjustable Bilstein is unnecessary, and a shock built without an exposed valve has one less failure point. Simple..

We could argue this all day... you're right in that Schrader valves (and every other valve for that matter) CAN cause problems. They also come in different quality levels. I've yet to read of anyone other than Mike having an issue with valves FCM installed (and he admits the valves themselves weren't the problem). I've owned a set and had them on the street for 2+ years personally. So IMO the quality of the valves and their functionality/durability isn't in question. There are times you just have to accept the imperfect world and take the (slight) risk something may eventually not work.


Originally Posted by Thucydides (Post 744749)
But back to these shocks. You have to take the shocks off to repair them anyway, so I would certainly replace the fluid as it's been compromised by cavitation. That means opening the shocks. While you're in there you might as well have a look at the valve shims, as they take a beating from cavitation too. None of this is particularly expensive, and you'll know at least that part of your suspension is right.

Agreed on all counts... and it's what I've basically been saying all along.


Originally Posted by Thucydides (Post 744749)
Are the valves on the Xida's even Schraders? If so, they look as though they're shielded against debris. Might be a useful upgrade for Shaikh to consider if it's more than just a cosmetic improvement..

Haven't seen a XIDA up close to say but as long as it's not some exotic/proprietary thing, it wouldn't be a bad thing. If nothing else you might gain enough room to not have to worry which direction the shocks are mounted. That said, if you can't pay that much attention to your assembly of a track car, you probably ought to be paying someone else to do it.

falcon 07-04-2011 06:59 PM


Originally Posted by Rennkafer (Post 744744)
Bilstein has been using Schrader valves on race shocks for 40 years +... pretty much every gas charged race shock comes with a valve of one sort or another on it (including AST/Xidas as Hustler pointed out).

We could waste lots of time going "what if"... to no end at all. If the shock bodies aren't damaged, there's no reason not to replace the valves, check the oil fill and recharge the gas. Then Mike can run them and see if he likes them, if not he's got functional shocks to sell and make up part of the cost of better pieces. What he has right now are two large paperweights.

My SD bils didn't come with a valve?

Thucydides 07-04-2011 07:03 PM


Originally Posted by falcon (Post 744830)
My SD bils didn't come with a valve?

You don't know?

danny2747 07-27-2011 08:47 PM

Mine came with Presta Valves. JK!


All times are GMT -4. The time now is 11:58 AM.


© 2024 MH Sub I, LLC dba Internet Brands