RC Shock Dyno Test Results
#16
I would like to know if there is really much difference between the Kyosho x-gear springs, TLR low frequency springs, and the others.
I also would like to know if the type of o-rings make a diffrence. O-ring vs grooved vs x-ring.
I also would like to know if the type of o-rings make a diffrence. O-ring vs grooved vs x-ring.
#18
I'd love to see how a Shepherd onroad shock with its spring loaded floating piston design for volume compensation does. I can send you one if your dyno can handle shorter shocks. PM me if interested.
#19
That sounds like the old Delta shock design. They worked great but are hard to build consistently.
#21
Sort of except the Shepherd piston is at the top just like a bladder and it's probably the easiest, most consistent and long lasting design I've ever used. It's just a slightly updated version of the good old Picco shock that people have loved since the 90s.
#22
this is too cool thank you very much icecyc1
#23
#24
like the test show bladder with foam is real consistent which is a good pick on a track where you have similar conditions from start to finish(for sure what i would pick for onroad) this is also what i like most the time for 1/8 buggy i guess because i run higher oil and having more weight the 1/8 conditions dont change as much as the smaller 1/10 on the same track.
#25
Thanks everyone for the comments!
I'm very excited to see the positive comments from the report. I really hope everyone learns from it. Like I said, I'll be using your comments to come up with further test plans that will hopefully drill down into further details that you all would like to know.
Some of your ideas will help me to develop a test (like the friction, or the long/short stroke) tests to best understand the effects. Some involve specific products, which I probably can't test specifically, but I'll try to design a test in general to cover the physics involved.
I think my next plan is to come up with a way to measure higher speed data for the Impact Testing (like your car will see on jumps). This seems to be highly desired data, so it will give the biggest benefit at this point.
The bladder test seemed to raise a lot of comments, so I'd like to go deeper into that as well. I have to say this test was a one data sample test. I only used one bladder. I was intrigued that the data looked as it did, with the collapse, but I was able to get rid of it by not venting the bladder. That told a great story. But, to be thorough, I should test several bladders, they are NOT all the same for sure. I'll be getting my hands on some soon, so I'll test and post results.
I'll also be doing a more thorough study of pistons. I think the flat pistons have shown what they do pretty consistently now (except I need to include high impact velocities still), so I'll focus on the fancy pistons. I will say I have a couple versions right now, and I did a limited single test, and yes, it did behave as the manufacturer claims, at least in the one test I did run.
I do want to say that my testing is not intended to glorify or bash any manufacturer, so I'll try to keep the results generic. But, I will likely post a photo of the test specimen, and chances are, people may figure it out due to the unique look. I just want people to be informed, and if a company makes something that should help performance the way they say, then the truth will be evident in the data. I also can't test every combination from every manufacturer there is either. I wish I could, but the money and time (mostly the time) it would take is beyond my limited resources.
I'm currently focused on Off-road shocks because that is what I own. I have some 1/10th big bore, and some 1/8th big bore shocks that I'll be doing the majority of my test work on. I don't have any experience with on-road, so that might not be for a while (sorry!), but hopefully the general trends and physics apply just the same. Maybe some day, I'll get a chance to test on-road shocks too, but I've got a lot to learn at this point still.
There was one mention about the hysteresis of the dyno itself. Valid question. I will say that I spent a couple months working through the dyno and instrumentation issues before becoming comfortable enough with the end result data. What sealed the confidence deal was the fact that I got perfect lines with the bladder design (no hysteresis), and very repeatable curves with the emulsion (definite hysteresis). I believe if the dyno itself had hysteresis issues, it would have been evident in all runs. I have tremendous confidence in the data below 250mm/s, but above that I hesitate until I become more acquainted at those higher speeds. (it really seems quite fast, and it makes me afraid I'm going to wreck my shocks!)
Some of your ideas will help me to develop a test (like the friction, or the long/short stroke) tests to best understand the effects. Some involve specific products, which I probably can't test specifically, but I'll try to design a test in general to cover the physics involved.
I think my next plan is to come up with a way to measure higher speed data for the Impact Testing (like your car will see on jumps). This seems to be highly desired data, so it will give the biggest benefit at this point.
The bladder test seemed to raise a lot of comments, so I'd like to go deeper into that as well. I have to say this test was a one data sample test. I only used one bladder. I was intrigued that the data looked as it did, with the collapse, but I was able to get rid of it by not venting the bladder. That told a great story. But, to be thorough, I should test several bladders, they are NOT all the same for sure. I'll be getting my hands on some soon, so I'll test and post results.
I'll also be doing a more thorough study of pistons. I think the flat pistons have shown what they do pretty consistently now (except I need to include high impact velocities still), so I'll focus on the fancy pistons. I will say I have a couple versions right now, and I did a limited single test, and yes, it did behave as the manufacturer claims, at least in the one test I did run.
I do want to say that my testing is not intended to glorify or bash any manufacturer, so I'll try to keep the results generic. But, I will likely post a photo of the test specimen, and chances are, people may figure it out due to the unique look. I just want people to be informed, and if a company makes something that should help performance the way they say, then the truth will be evident in the data. I also can't test every combination from every manufacturer there is either. I wish I could, but the money and time (mostly the time) it would take is beyond my limited resources.
I'm currently focused on Off-road shocks because that is what I own. I have some 1/10th big bore, and some 1/8th big bore shocks that I'll be doing the majority of my test work on. I don't have any experience with on-road, so that might not be for a while (sorry!), but hopefully the general trends and physics apply just the same. Maybe some day, I'll get a chance to test on-road shocks too, but I've got a lot to learn at this point still.
There was one mention about the hysteresis of the dyno itself. Valid question. I will say that I spent a couple months working through the dyno and instrumentation issues before becoming comfortable enough with the end result data. What sealed the confidence deal was the fact that I got perfect lines with the bladder design (no hysteresis), and very repeatable curves with the emulsion (definite hysteresis). I believe if the dyno itself had hysteresis issues, it would have been evident in all runs. I have tremendous confidence in the data below 250mm/s, but above that I hesitate until I become more acquainted at those higher speeds. (it really seems quite fast, and it makes me afraid I'm going to wreck my shocks!)
#26
Thanks for the feedback.
#27
Springs are out of scope at this point, but it is interesting, and I'll keep it in mind for the future. Most of the time springs can be characterized simply with a scale and a ruler because they are displacement dependent and not velocity dependent. I'm not too familiar with the claims of the springs you mentioned.
#28
A word on x-ring vs. O-ring: While an o-ring comparison may be useful, there are many other variables in a shock's working friction. Some shocks require different guide bushing configurations to work correctly. These variables may reduce the efficacy of these tests.
What I like about what has been done so far is that the things these tests have focused on are consistent across brand and type.
What I like about what has been done so far is that the things these tests have focused on are consistent across brand and type.
#29
Tech Adept
Interesting observations. I find conditions and performance changes more with 1/8. Longer mains, rougher track, bigger hits, bigger temperature swinga (outdoors), etc. I've always found it curious how we keep landing on the emulsion setup in 1/10 since we run in comparatively consistent conditions.
#30
no is said same track and for a 1/10 scale car vs 1/8 on same track. so to scale! the track is more inconsistent as a %... i run much lighter oil in 1/10 scale car so it moves around a lot more and at a higher rate of speed even more than my 1/8 at more weight. so on the same track my 1/10 shock are working harder as far as movement. yes in a long main the shock will come inconsistent with heat but i was talking about track inconsistent effect on movement of the shock. now cuz emulsion have bad inconsistency as a shock it might be another good reason not to run it on 1/8 buggy in long mains for the heat expansion of air vs just oil(but not sure of that test)!!!