SCX10 II Suspension Set Up

[macman809]

Hi I am looking for some help here, I know a little knowledge can be dangerous, and yes I have been playing/experimenting with my suspension set up on my RTR Axial Honcho SCX10 ii.
My first move was to re tune the stock shocks but I had issues with leaking, I moved over to Traxxas GTS TRX4 shocks which have been great.
I have been trying to achieve a 60:40 Compression to Droop/Sag ratio, as I think that this seems to be a good way to go. The principle is that you balance your axle so that when you climb up on an obstacle with your driver front wheel as the front driver shock reaches its set compression rate of 60% it will start to drop the passenger side wheel down which works to level the chassis out.
I have been very please with the trucks balance on steep and technical climbs that I wanted to try and get this set up as near to a perfect 60:40 front and rear, and this is where my trouble started.
I managed to get the front to a perfect 60:40 ratio which works very well, but when I turned my attention to the rear not so much. The best I could get the rear settings to was a 73:27 ratio. Any efforts trying to improve on that did not work.
I have reversed the rear shock mounts which allows you to move the rear shock from a stock 90 degrees to the axle to as far forward as approx. 30 degrees which does change the action of the suspension on the rear in a positive light IMHO. I tried using different spring weights/tension which did not work, softer springs don't make any significant difference and harder/stronger springs move me away from the 73% compression to a much higher compression rate of closer to 80% compression, Oil weights whilst changing the action/response time don't change the actual physical mumbers (extension/compression) much at all.
I even started moving the angle of the shock back towards the original upright 90 setting again with very little effect on the actual numbers.
In order to more droop (moving from 27% up to 40%) I need to reduce the preload on the spring but I am at the full extent of preload reduction, anymore and the collar wont even be in contact with spring on full extension.
So where do I go from here? The stock shocks and the GTS TRX4s are both 90mm center to center, should I look at a longer shock would that give me more scope or does running a dual spring set up work as I am at a loss here, I don't know where or how to proceed .
I am not saying the truck doesn't handle well I am not displeased with its performance and climbing ability but I am curious that if I could achieve a perfect 60:40 on the rear would it be better.

 

[KikRocks]

with so little weight in the rear of the vehicle it might be hard without going super lite on the springs no? I guess u could limit the travel of the shock by putting some fuel tubing inside although u will also lose overall length of the shock.

 

[mass-hole]

You tried the yellow TRX4 springs? They are very light, like 25% less than the whites that normal come on the front of the trx4 sport kit. I wouod think being 25% lower spring rate means they need to compress 25% more to hold the weight up.

Also, longer shocks would do it, but you need to move the shock mounts apart to fit them and still get the same ride height and bottom out at the same point. I am running 120mm Hot Racing shocks on my TRX4 and still able to sit at factory ride height but i had to get extended shock towers and screw around with the springs.

Long Travel Buildup
https://r.tapatalk.com/shareLink?sh...om/forum/showthread.php?t=608175&share_type=t

 

[macman809]

Thanks for the feedback, in answer to the have I used the softer 0.22lb/in Yellow springs yes I have, I thought they would be the answer but alas no, they made almost no difference.
Thinking about KikRocks observation of the weight issue I added weight to the truck and that does make a difference and after messing around with different weights I can get the desired effect by adding weight. The truck is still using the stock Axial Honcho body and cage with no driver or interior or spare wheel all of which I intend to add. If I add 130grams to the chassis I get the desired result. So I will start to work on the body and I think by adding a driver and a spare wheel I should start to see a difference. Thanks for the input at least I'm moving on the right direction now.

 

[macman809]

Re Traxxas Red Pistons vs stock black pistons, it maybe worth checking the black piston for deformation, I had problems with my rear shocks binding and when I stripped them down I found that the pistons were binding in the shock tubes, I swopped out shock shafts to make sure they were not bent, and I also swopped out the front shaft/pistons and they worked fine, so I replaced the black pistons and all was well (so far). I did try the red pistons but I prefer the closer fit of the black pistons as the stock black pistons are approx. 7.16mm dia, compared to the 6.94mm dia of the red pistons. I use 20wt Oil and that seems to work well. I think if you use anything over the 30wt the red pistons might be a better choice.

 

[Natedog]

THe Traxxas TRX-4 shocks are very good! In general standing the shocks at or near vertical is best, adjust the spring rate (usually same or little stiffer rear ime), preload and the height of the upper mounting point to get the proper settings. 90mm is a very good length for cralwers too, occasionally even shorter. HTH