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Want to see what happens inside your shock?

top_dog

Monkey
Jan 27, 2006
209
0
Australia
A super cool video of a racing car shock on a dyno. The difference with this video is that they've made a clear body for the shock, so you can see the cavitation, and if you look carefully even see the shims bend. Amazing.

http://www.suspensionhotline.com/dyno/images/VMA_clear_shock2.wmv

I'll be changing my oil way more often, now that I've seen what a hard time it gets.

And the second video shows a lap of a track being fed into the dyno and shock doing its stuff. Huge velocities involved for sure. You see the piston at the bottom, then at the top, but you don't see how it got there, except for the bubbles telling the story.

http://www.suspensionhotline.com/dyno/images/VMA_clear_shock1.wmv

Jaw dropping stuff. I thought so anyway.:busted:
 

ÆX

Turbo Monkey
Sep 8, 2001
4,921
0
amarillo
Well thats 2 min. of my life I will NEVER get back
what are you talking about.

that is a great video for anyone who wants to see what is
happing to there shock. maybe you have seen this before?

if so you should just have not clicked on the tread. gheeeesh.
 

General Lee

Turbo Monkey
Oct 16, 2003
2,867
0
The 802
i heard him say, "This is the left front at Charlotte," but I'm wondering if you know what kind of car/truck/ and track to which he is referring. I'm guessing it's not off-road, every POV camera shot i've seen of off-road suspension shows them to be far more active. this one seems to be operating over only a small range of its travel; track racing perhaps?

just guessing, of course.

edit: silly me, the first sentence is 'A super cool video of a racing car shock on a dyno.'
 

MttyTee

Monkey
Jun 20, 2007
209
0
Back on the east coast!
Nice post. The vids originally (as far as I know) came from Roehrig Engineering, who is a suspension dyno manufacturer located in NC and involved heavily with NASCAR testing. One of the cool features with their electromagnetic dynos and software, is the ability to take real track data (from a data acquisition system) and run it on the dyno.

There are a few other videos at the bottom. http://www.roehrigengineering.com/cart/pages.php?pageid=2
 

General Lee

Turbo Monkey
Oct 16, 2003
2,867
0
The 802
Nice post. The vids originally (as far as I know) came from Roehrig Engineering, who is a suspension dyno manufacturer located in NC and involved heavily with NASCAR testing. One of the cool features with their electromagnetic dynos and software, is the ability to take real track data (from a data acquisition system) and run it on the dyno.

There are a few other videos at the bottom. http://www.roehrigengineering.com/cart/pages.php?pageid=2
probably overkill for 99% of us, but it would be pretty neat to be able to take a test run on course then download the data and be able to test different setting in the pits (or elsewhere via email) before taking another run. Actually, i wouldn't be surprised if all the elves over at the Honda tent were doing just that. i know back in the day the Sunn team used to log data and set up their bikes in advance the following year or on a similar track. but i wonder if they could do it in real-time 8-10 years ago.

i could see that being a big advantage for guys like Barel who need to 'know' their bike is set up just right. The Rennies on the circuit probably couldn't be bothered.


and is MttyTee the alias for Matt Timmerman? If so, howdy from back east way back when.
 
probably overkill for 99% of us, but it would be pretty neat to be able to take a test run on course then download the data and be able to test different setting in the pits (or elsewhere via email) before taking another run. Actually, i wouldn't be surprised if all the elves over at the Honda tent were doing just that.
I kind of remember hearing about something like this going on inside the Honda tent. Mainly just speculation I'm sure, but sounds really plausable. I definately saw a pic of an unattached Showa shock that had a "Fort William" tag tied to it in one of the mags.

At Interbike's on dirt demo this year (07 show/08 products) Paul and Malcom over at Cane Creek had data aquisition software on a demo bike built with the Ohlins Double Barrel. Unfortunately, the battery died when I took the bike out and I couldn't actually get any data out of it, but if I recall correctly, the info could be downloaded into a blackberry in the pits, e-mailed to a computer with all the suspension logistics, and then it would e-mail you back in the pits of what adjustments to make for that trail or course for optimum performance. It was really cool talking to those guys about it, and I wish it would have worked when I got to ride the bike.

Not a dyno, but still pretty neat.
 

kidwoo

Celebrating No-Pants Day
Aug 25, 2003
22,446
2,121
In my pants
I love how those guys can afford a dyno and the construction of a polymer bodied shock but can't afford a freakin tripod for the camera:busted:



Cool stuff though.

Thanks for posting that.
 

jcook90

Turbo Monkey
Mar 3, 2006
1,211
0
Connecticut
Thats real cool, never would have thought the oil would cavitate.

Quick question about suspension and how the reservoirs work. I know that the rebound is controlled by oil in the main piston passing through a valve attached to the shock shaft or w/e it is and filling the space behind the valve. What causes the oil to flow into the reservoir and through the compression valves on a lot of shocks if it can just pass through the rebound valve into this space created?
 
^^haha seriously...

amazing stuff, i've always wanted to see cavitation happen in a easily viewable environment...
its amazing how much force is put into shocks and how well they handle it... there is insane positive pressure on one end of the piston while the exact opposite forces are on the other end...

i have seen and felt cavitation underwater from my fins on my surfboard, as well as hearing it on a hydrophone while recording dolphins containing a bait ball.... amazing stuff
 

muddy beast

Turbo Monkey
Nov 26, 2005
1,819
0
that was pretty cool.

I never really thought about what's going on inside my shocks beyond how the dampenings in different companys shocks/suspension are supposed to work...
 

TWeerts

Monkey
Jan 7, 2007
473
0
The Area Bay
Cool. I'd like to see Push do something like that with some real data from a DH run.
im pretty sure they already do that. they have special data acquisition jigs that are fixed to the bikes and the reader for those thingys are plugged into a computer...that is the whole idea behind PUSH, they just apply the same thing to every ones shock (given your specified ride qualities, weight, and ride style).
 

Patan-DH

Monkey
Jun 9, 2007
458
0
Patagonia
thats why the quality of the oil is so important, and the oil changes a must. I would like to see the same video taken with infrared vision lenses just to see the temperature changes