More here than meets the eye. Odd physics

[IronArcher]

So, being a newb, I’ve made it a part time job to watch videos and read reviews on prospective RC cars for rock crawling.
A lot of the questions I am coming up with are based on the wrong answers to many questions that seemed obvious.

Here is a good 3 way example based on RTR cars I have been very interested in:
Element Sendera, Ecto, and Gatekeeper.

The main differences are
Sendera has “conventional” 4link rear suspension, and a medium (in this group) weight body
Ecto has swingarm/sway bar rear suspension and light body
Gatekeeper has the same swingarm/sway bar rear suspension, and a VERY heavy body (3x the weight of the Ecto).

Conventional wisdom would suggest that the gatekeeper wouldn’t do as well crawling as the Ecto. Much higher center of gravity and all. But in head to head tests, at least on stock, or mostly stock trucks, the Gatekeeper wins.
Conventional wisdom also suggests that a traditional 4 link setup is “better” for rocks than a swingarm, yet the same driver driving the trail truck and Sendera found the Ecto performed much better.
There was a theory, that the sway bar on the swingarm hurt articulation and trail performance. This was both right and wrong, and removing the sway bar made the truck far less capable, even though the suspension did indeed flex more. This was particularly noticeable in climbs and side hills.

The current prevailing theory is that the Ecto could be made to be the dominant of the 3 by adding a lot of weight to the wheels and axles, and individuals doing this report/show very good performance.

But I haven’t found any comparing an Ecto with lots of brass to a gatekeeper with lots of brass.
One would think this has an obvious answer, yet, those same “obvious answers” have been very wrong time and again.

Your thoughts?

 

[DrIsotope]

At least with me, this raises more questions than it prompts me to provide answers. You mentioned "...in head to head tests, at least on stock, or mostly stock trucks, the Gatekeeper wins." What kind of tests? Under what circumstances? There's no way on this green earth that the GK is taking the Ecto in approach nor departure, and I cannot see the GK doing well in sidehilling either. If we're talking purely anecdotal "testing," along the lines of "they were driven at the same time," then any result could be had. Repeatably? <shrug>

Four link will undoubtedly (and has been proven) to be more capable at crawling... at extremes. In a contest of RTR vs. RTR, sooooo many other things are going to give way before the weaknesses of the trailing arms make themselves known. If this was RTR, then it's stock Grabbers all around, and they're a solid C- tire, so nothing any of the three rigs did can transcend the mediocrity of the tires.

A swaybar should improve sidehill performance (the loaded low side pushes the light hight side down) so no surprise at all that it got worse with the bar disconnected.

If you want to make this more of a test, run them all without bodies. There is the non-removable variable of the Sendero having a shorter wheelbase. IME, the Sendero with the Ecto body on it would be the best performer without mods.

 

[ferp420]

So, being a newb, I’ve made it a part time job to watch videos and read reviews on prospective RC cars for rock crawling.
A lot of the questions I am coming up with are based on the wrong answers to many questions that seemed obvious.

Here is a good 3 way example based on RTR cars I have been very interested in:
Element Sendera, Ecto, and Gatekeeper.

The main differences are
Sendera has “conventional” 4link rear suspension, and a medium (in this group) weight body
Ecto has swingarm/sway bar rear suspension and light body
Gatekeeper has the same swingarm/sway bar rear suspension, and a VERY heavy body (3x the weight of the Ecto).

Conventional wisdom would suggest that the gatekeeper wouldn’t do as well crawling as the Ecto. Much higher center of gravity and all. But in head to head tests, at least on stock, or mostly stock trucks, the Gatekeeper wins.
Conventional wisdom also suggests that a traditional 4 link setup is “better” for rocks than a swingarm, yet the same driver driving the trail truck and Sendera found the Ecto performed much better.
There was a theory, that the sway bar on the swingarm hurt articulation and trail performance. This was both right and wrong, and removing the sway bar made the truck far less capable, even though the suspension did indeed flex more. This was particularly noticeable in climbs and side hills.

The current prevailing theory is that the Ecto could be made to be the dominant of the 3 by adding a lot of weight to the wheels and axles, and individuals doing this report/show very good performance.

But I haven’t found any comparing an Ecto with lots of brass to a gatekeeper with lots of brass.
One would think this has an obvious answer, yet, those same “obvious answers” have been very wrong time and again.

Your thoughts?

it all comes down to preferance and style



you could be class 7 champian of the universe and your rig might not work for me



dont let you tube tell you whats best for you

 

[IronArcher]

@DrIsotope
One guy I watched a lot was “RC-TNT”. He makes runs on the same course, same day. He runs multiple tests on the same course, so while not scientific, it’s relatively consistent. And multiple runs of the same car normally produces the same “score”.
More importantly, you can see how the cars work on the course. The extra mass of the gatekeeper seems to just slow everything down a little. He does say that it is more top heavy, but also more stable.

With the rear suspension, I’ve watched numerous channels testing both the gatekeeper and Ecto against each other and against lots of other cars with 4 link rear suspensions. The Elements always do very well. Often the main issue with the Ecto is as you mentioned, tires, but also not enough weight to get the tires to want to do anything. Even in tests with modified rigs, when they add weight, the Ecto wakes up. I’m sure in the ultra high end cars, few use the trailing arm suspension. But in $500 or less cars, the trailing arm cars seem to be the equal to most 4 link cars, and better than many.
Like I said, it’s very confusing .

Please do not take this as an argument. I’m quite certain you are far more versed in all this than I am. But I rarely find people who arent impressed with the trailing arm Element cars, I’m just trying to explain where I am getting the impressions I have.

@ferp420
I understand it’s more driver than anything, and quite often I just watch to see what the cars are doing, rather than listen to them praise their new car ��.
But we need a car to play, I’m just trying not to handicap myself too much��

 

[twade984]

@DrIsotope
One guy I watched a lot was “RC-TNT”. He makes runs on the same course, same day. He runs multiple tests on the same course, so while not scientific, it’s relatively consistent. And multiple runs of the same car normally produces the same “score”.
More importantly, you can see how the cars work on the course. The extra mass of the gatekeeper seems to just slow everything down a little. He does say that it is more top heavy, but also more stable.

With the rear suspension, I’ve watched numerous channels testing both the gatekeeper and Ecto against each other and against lots of other cars with 4 link rear suspensions. The Elements always do very well. Often the main issue with the Ecto is as you mentioned, tires, but also not enough weight to get the tires to want to do anything. Even in tests with modified rigs, when they add weight, the Ecto wakes up. I’m sure in the ultra high end cars, few use the trailing arm suspension. But in $500 or less cars, the trailing arm cars seem to be the equal to most 4 link cars, and better than many.
Like I said, it’s very confusing .

Please do not take this as an argument. I’m quite certain you are far more versed in all this than I am. But I rarely find people who arent impressed with the trailing arm Element cars, I’m just trying to explain where I am getting the impressions I have.

@ferp420
I understand it’s more driver than anything, and quite often I just watch to see what the cars are doing, rather than listen to them praise their new car .
But we need a car to play, I’m just trying not to handicap myself too much

If you’re interested in YouTube videos, take a look at the Crawler Canyon channel. Many hours of content posted there, and as a matter of fact, they even post regularly on RCC. I’ll let you figure out who it might be. Only hint, it isn’t me.

https://youtube.com/@CrawlerCanyon

Last thing, I like to keep in mind that everyone has different priorities, preferences, and uses for their rigs. So while getting opinions and watching videos is helpful, nothing can replace just getting out there and experiencing for yourself.


Sent from my iPhone using Tapatalk

 

[smog]

If you’re interested in YouTube videos, take a look at the Crawler Canyon channel. Many hours of content posted there, and as a matter of fact, they even post regularly on RCC. I’ll let you figure out who it might be. Only hint, it isn’t me.

nothing can replace just getting out there and experiencing for yourself.

I don't know who Crawler Canyon is either, but have enjoyed his tire testing videos. I find there is a subtle humor in his delivery

Personally, I have yet to run a heavy body that performs well on any terrain that has significant camber or incline. Can't say I have ever seen a video that has made me question my experience with this. Sure good driving can take a rig across a line that reaches the edge of it's tipping point but good driving doesn't change a rigs center of gravity.

All said it can be fun to crawl a high center of gravity rig. It all depends on the terrain. Having too capable a crawler on mild terrain can steal away the challenge and hence the joy. ..perhaps I digress

 

[IronArcher]

Thanks to all the replies, and quality lack of bashing (the bad kind, not the RC kind [emoji23])

I have decided to go with the Gate keeper, and got a great deal.

With this rig, I can learn to drive with a heavy car, change it to the lighter “Ecto” and even swap out the trailing arm suspension if I want to blame it for holding me back![emoji1787]

In another thread, I said I might do a video of my own on that once I don’t suck, but I’m thinking maybe do it now while I still suck, then revisit it once I have a clue and see how much of a difference that makes.

I can’t wait to get this thing in!

Now I just need to figure out batteries and chargers Lol!

 

[smog]

You will need a shorty pack for the Gatekeeper/Ecto.


Edit: Something this size

https://www.amainhobbies.com/protek...po-battery-11.4v-4800mah-ptk-5116-22/p1370771

 

[IronArcher]

Thanks!


Sent from my iPhone using Tapatalk

 

[Druxus]

Crawler canyon is the Drisotope who was the first person to respond to your thread.