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Spring rate vs linear spring vs progressive spring vs preload MYTH

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If you could lean the shock in far enough that it’s parallel to the lower arm, the effective spring rate and damping rate would be zero. Going beyond that, the spring would start to resist downtravel instead of uptravel.
Oh i see. And damn that video is really good. I like this guy lol
More adjustability here makes for a better handling car generally, but we can clearly be farting around with infinite adjustments for, well, infinity! Lol!
Yea there is infinite possibilities lol


I did try something funky. First a put rear shocks in front. I mounted the shocks on the clipless system so its higher. I really like the handling and the big travel.

I crashed and one of the cap in front popped and i lost all the oil. I continued anyway. At first it was funny but the shock without oil did stupidly good.

I then tried without oil in both front shocks. My car didnt performed as well as it did without oil lol i just want to try with the rear too. I'm feeling wierd tho. Its not supposed to work with no oil lol but i do heavy off roading right now. The car is so planted its crazy how the tires sticks to the ground.

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Yeah, gotta try different oil in the shocks and dial your front end in.
I'm glad you have it glued down and its h`ndling better!!!
Its funny how moving the mounting points changed the handling up, huh?
Nice work!
I really like the long shocks on all 4 wheels and yea changing shock positions is alot of fun. Its diy and super sketchy but its fun. And right now, I'm sure nobody have the same truck. Its unique.

But i can't wrap my head around the fact that i prefer shovks with no oils... Its not meant to be like that at all. I may try half oil to see what it does or super thin like 20 wt.

I have no oil in all four shocks right now. I have so much tork its insane and fast. My wheels never leaves the ground. But forget about doing jumps tho xd
 
I wonder if your springs have much to do with the way it handles better for your driving style??? I would get those shocks live, even with a light oil personally.
I don't like ultra stiff shocks unless for speed runs or onroad generally, also.
You'll prob end up trying a few different weight oils before you get the "magic feel".
 
I wonder if your springs have much to do with the way it handles better for your driving style??? I would get those shocks live, even with a light oil personally.
I don't like ultra stiff shocks unless for speed runs or onroad generally, also.
You'll prob end up trying a few different weight oils before you get the "magic feel".
I didnt tried other springs with no oil in shocks yet. Currently i have the stock traxxas in front and silver (medium) HR in rear. A bit of preloads on both. I tried alot of differwnt springs before and the mediums feels right most of the time. I need to try stiffer and softer to see how it react without oil.

I recommend to everyone to try it tho. By removing a factor (oil) its easier to isolated the other factors (springs and angles).

I feel that stating that oil only change speed is oversimplified. Springs does that too. Clearly you need more force (or weight) to move an oil filled shock. So i may be able to run softer springs without oil.

Whats making handling better right now is that the wheels move up and down but not the truck. Before i would hit a bump and the shocks didnt have time to compress or decompress. But like i said before, my driving style and the terrain i drive on is a niche.
 
The oil is more about controlling the reststance and rebound of the spring where the spring is about keeping the weight of the kit properly suspended.
If I ever get back on my Frankenbuild, I'm likely to buy a set of the HR springs to try.
Progressive springs seem like an obvious upgrade but as this whole post shows, consequence arise with almost every change... hoping for positive consequence and killer handling!
These springs seem like its very much up to the driver to love or hate.
 
I feel that stating that oil only change speed is oversimplified. Springs does that too. Clearly you need more force (or weight) to move an oil filled shock. So i may be able to run softer springs without oil.
Oils are definitely not about the speed only. When you land a high jump, it’s mostly your choice of oil that determines whether the landing is soft like a sack of flour, or if the chassis hits the ground without really slowing down. No reasonable spring will do much to soften the landing from a high jump.

I think the reason you prefer the handling without oil is that the wheels go over bumps more easily without disrupting the chassis that much. Try lightweight oils and/or larger piston holes.

Softer springs without oil is a recipe for bottoming out even the smallest jumps.
 
Progressive springs seem like an obvious upgrade but as this whole post shows, consequence arise with almost every change...
Ya i wasn't so sure about progressive springs thats why i started this thread. Maybe I'm changing opinion right now but i need to try hr linear springs. Now that i raised the car alot progressive works good. The way i think suspension is different from when i had the stock slash.
I think the reason you prefer the handling without oil is that the wheels go over bumps more easily without disrupting the chassis that much. Try lightweight oils and/or larger piston holes.

Softer springs without oil is a recipe for bottoming out even the smallest jumps.
Ya i just need to forget about jumps. "Tiny" ones or ok tho, but on samd or dirt. And ya, like you said, i just like when the chassis almost dont move. Ill try light oil and more piston holes. Yes its fun without oil bit i feel a bit like a criminal haha

Oh and i understood that you really need to drive. Theory helps but there is so much physics envolved, you need to feel it.
 
I think you can get the shocks and springs to work well over a good variety of terrain, maybe not ALL, but smaller and larger jumps shouldn't be a challange for a Slash.
If you keep experimenting with oils and springs, you will almost definitely find "happy place"!!!
 
Been there done that. If your truck's weight is near stock run 0.90 spring rate with 35wt shock fluid for the front. For the rear just match what's run on a 2wd Rustler. There's a lot of leverage on the front shocks so you have to run them stiff to balance out your ride.
Hey. Little update here.
So the "no oil" fun is over haha i decided to put back 30wt back and front. I have the big bores in back (stock 2 holes piston) and rear ultras in front (stock 1 hole piston). I popped a front shock cap again and love how the shock with no oils reacted, AGAIN lol so i tried 2 holes piston in front. It didnt feel right tho. Its seems like the rear takes all the impact and it shift the car suddently. It makes it unstable. Driveable but..

It was a bit of a pain to change the pistons so i think ill try to put 40wt to see the difference.

I feel that going 3 holes piston in rear instead of 2 may be a good choice ill try that.
I dont know if i want more pack or less.
Maybe the best setup would be one hole piston with 20wt oil. Ill try that too :)
 
This is great! You will get it dialled in to where you love it at speed AND it will take the big jumps!
I am in the middle of dialing in my shocks too. Just ordered up some 200cst. Can't wait to get it in and try this buggy out again!!! I'm getting close!
 
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