Sag vs No Sag Suspension
 

I wanted to start a discussion about sag vs no-sag in an MOA to help get an education. I know there are preferences and variations in chassis design, but the principles should apply to any rig..


I have run with the shocks topped out but I am currently trying about 30% sag in the shocks with medium(ish) mini T springs. The no-preload sag makes the truck lay up very well on suspension breaks, and it follows every contour of every transition.


On the down side, I have been occasionally getting some wheel lift when the oil leaks down or it's in a good bind.


On the same lines with high preload and topped out shocks, It handles well, but when it does lift a tire it is most likely going to go all the way over because the oppisite corner shock is loaded and releases all it's energy quickly.


So I'd like some opinions (and some facts) ... I'm trying to find the differences between a stronger spring with no preload and a softer spring loaded up. You can get the same sag with either.

Are there any serious (cons) to running sag in your suspension? I have been unable to find any yet...

Re: Sag vs No Sag Suspension
 

Good topic, in for the tech.

Re: Sag vs No Sag Suspension
 

I think this is a great topic. We should add info for all crawler, scalers, and rock racer types. I have seen so many different setups but I am also not sure the best setup for what. I have found that the oil weight makes more of a difference than the actual springs and sag position. Im still learning so give us some info..

Re: Sag vs No Sag Suspension
 

hmm this is hard for me to describe. i used to run losi 4in shocks with golds and no preload so it had some sag in it. the truck seemed to run very well and did excellent break overs but the truck felt sloppy and not as precise as i would like. later i switched to traxxas big bores with the mini t springs and it seemed to take out alot of slop if that makes sense. like i said its hard for me to describe but it just seemed more predictable for me. this is probabyl just a pointless post on my account but its my eperience with it.

Re: Sag vs No Sag Suspension
 

Big bores shafts are usually sealed a little tighter and are a little slower,so I do know what you are saying... and they do seem to handle sag a little better.

I'm using power strokes on my XR right now, so I have to contend with a little slopiness. They leak down badly and cause funky lifting when they get low.

I haven't tested it much, but it seems like more link seperation at the axle helps control things when running sag. In the little bit of testing I have done, it seems to keep the tires down better.

Re: Sag vs No Sag Suspension
 

I have noticed the same thing if your speaking of more separation at the axle. Definitely doesnt lift front as much when digging up hill, binds, etc. Downhill control seems smoother as well.

Re: Sag vs No Sag Suspension
 

very noticeable difference with link separation. when running stock losi spec or even 8mm above, the truck was more unpredictable than i really like. since then i've increased over an inch over stock, and with a new chassis as well, its very smooth, predictable, and just feels a bit more forgiving than the stock losi chassis. running internally sprung losi shocks with rpm 2 stage pistons. i have to say that the rpm pistons are a thing of beauty once you get them tuned out.

Re: Sag vs No Sag Suspension
 

My experience is that a sag/droop works best in the front. Very hard to accidentally roll over. I see time and time again fully sprung trucks deflecting off of an obstical and rolling over. Almost always the front causing it. So I run a no bottom droop. Basically a droop that rides mid stroke and stiff internal springs that keep the axle from falling.

In the rear I run sprung shocks with a small amount of sag. Sag in the rear hinders breakovers but has better terrain following capabilities.

Re: Sag vs No Sag Suspension
 

I'm a tech whore too. Sometimes just can't get enough. "Gettin' there" now between this thread and Jeremy's stearing thread.

Re: Sag vs No Sag Suspension
 

i run about 60% sag in my rig. so fare the only disavantage that i have to deal with over having full sprung, is not being able to float a tire over a hole.

Re: Sag vs No Sag Suspension
 

yeah being able to float a hole is a really good thing. guess i never truly addressed the question previously, running about an 1/4" of sag at ride height, shock setup:

losi 4" shocks
trinity double seal TRITEP3010 o-rings
midwest fastener #8 springs (i'll punch out the spring rate next time i have them out)
rpm 2 stage pistons-light/medium kit:
.......front: white dynamic, blue static (lightest, med.)
.......rear: yellow dynamic, blue static (heaviest in kit, med.)
30wt oil all around.
12mm limiters all around.

the double seal o-rings are actually doing as good or better than the mip blue seals i had in there, and as i said before, the rpm 2 stages are a godsend.

Re: Sag vs No Sag Suspension
 

It's tougher to float over a hole, but you can load the opposite side of the corner you want to float to create lift that can get you over most gaps.

Re: Sag vs No Sag Suspension
 

Exactly what I was going to say.

After reading this thread I figured I would try sprung shocks again in the front.

About 300mah later I switched back to droop:ror: