Coilovers settings tip - reduce bounciness? - Toyota Yaris Forums

banifesto · 04-23-2012, 12:38 AM

Hi folks,

I got a BC coilovers, which I believe it is the same as Megan, etc.

For the fronts, I increased the height a little bit so that the wheel gaps are even with the rears.

Rears are left untouched, basically installed without adjusting anything.

At first the ride is somewhat bouncy, so I instructed the installer to increase the front springs preload to 5mm. This really helps on reducing the bounciness greatly.

After the coilovers have settled in, I can still feel a slight hint of bounciness, especially on low speeds (start-stop traffic) even on a smooth road. The bounce is subtle, but enough to get me nauseated.

A friend took a ride and he commented that the bounce feels unsettled. I've tried all damper settings (full soft, medium, full hard). The bounce becomes more apparent if I set the damper to be more stiff. At 10 clicks or lower, the bounce is acceptable but I'd like to make it perfect.

Any tips to get the best out of the coilovers? Bumpy is fine. I like a firm ride. I'm very sure the unsettled bounce feeling can be eliminated.

The bounciness is felt on the fronts, but who knows, it may be caused by the rears?

Should I adjust the rear springs preload? or increase the front preload to 10mm (close to 1/2 inch). Any inputs are very much appreciated!

Kaotic Lazagna · 04-23-2012, 01:35 AM

General rule is to never touch pre-load and adjust via shock length adjustment. Then set dampening to your liking. My friend's 8th gen Civic is much lower than my Vios (he's on BC coilovers and I'm on Tein springs/TRD dampers), and his car rides smoother than mine.

http://www.rx7club.com/showthread.php?t=600868

http://legacygt.com/forums/showthrea...s-181610.html?

banifesto · 04-23-2012, 03:31 AM

Thx Kaotic.

I did the preload adjustment as per recommended by BC. The fronts seem to be better after the adjustment. I haven't touch the rears as they are more tricky to adjust.

Ride height is fine at the moment. Just that tiny bit of unsettled bounce.

Kaotic Lazagna · 04-23-2012, 03:40 AM

NP.

I'd try it the general way of adjusting coilovers. See how it works out. What's your dampening set to?

Oh, and when I said BC earlier, I meant Buddy Club. haha

MUSKOKA800 · 04-23-2012, 10:13 PM

Bounciness = inadequate damping. Increase your rebound damping to control the springs.

banifesto · 04-23-2012, 11:23 PM

dampers set to 8 / 5 (from soft) for fronts and rears respectively.. smooth but too soft. the installer added more preload, subtle bounce seems to be gone but it also introduced a new way kind of bounce.. hard to explain but i think the front springs are too tight lol! too much preload methinks.

very contrast to the rears as they feel sharp without excessive bounce on whatever damping i put on.

i'll reset the preload back to 0 (so the springs are just snug with the perches) and adjust the damping appropriately. if the subtle bounce is back, i'll just add a little preload, maybe 3mm to see if it helps.

also, do coilovers need time to settle in?

Jason@SportsCar · 04-24-2012, 12:13 AM

You should never need preload, that is only an option because those shocks were not built properly for the application. A lot of these places buy shock bodies that have a range of length that will fit a dozen or more cars and then add hardware to fit a particular application, that is the only reason they have the additional height adjustment.

Sounds like you might be hitting the bump stop prematurely, or you may not have enough droop, check your travel.

banifesto · 04-24-2012, 10:20 PM

just redid the front springs all over again.. eased off the tension and retighten as per recommended by the tech support. bounce is nearly gone. all good now, just a matter of adjusting the damping. all DIY and the feeling is

adding more preload will just increases the height.. and too much preload is bad.

04-23-2012, 12:38 AM	#1
banifesto Drives: Yaris Sedan Join Date: Sep 2011 Location: Over there Posts: 11	Coilovers settings tip - reduce bounciness? Hi folks, I got a BC coilovers, which I believe it is the same as Megan, etc. For the fronts, I increased the height a little bit so that the wheel gaps are even with the rears. Rears are left untouched, basically installed without adjusting anything. At first the ride is somewhat bouncy, so I instructed the installer to increase the front springs preload to 5mm. This really helps on reducing the bounciness greatly. After the coilovers have settled in, I can still feel a slight hint of bounciness, especially on low speeds (start-stop traffic) even on a smooth road. The bounce is subtle, but enough to get me nauseated. A friend took a ride and he commented that the bounce feels unsettled. I've tried all damper settings (full soft, medium, full hard). The bounce becomes more apparent if I set the damper to be more stiff. At 10 clicks or lower, the bounce is acceptable but I'd like to make it perfect. Any tips to get the best out of the coilovers? Bumpy is fine. I like a firm ride. I'm very sure the unsettled bounce feeling can be eliminated. The bounciness is felt on the fronts, but who knows, it may be caused by the rears? Should I adjust the rear springs preload? or increase the front preload to 10mm (close to 1/2 inch). Any inputs are very much appreciated!

04-23-2012, 10:13 PM	#5
MUSKOKA800 Drives: Scion FRS RS2, ‘21 Crosstrek Join Date: Oct 2008 Location: Chatham, Ontario, Canada Posts: 1,729	Bounciness = inadequate damping. Increase your rebound damping to control the springs. __________________ TRD Upgrades: 18" Wheels wrapped in 215/35/18 PZero's, Sportivo Shocks/Struts, Lowering Springs, Swaybar, Axle-Back Exhaust, Oil Cap, Rad Cap, Signage. Aftermarket Goodies: Piggies SS, K&N Drop-In, Blitz S/C, DC Header, NST Pulley) Toyota Options/Accessories: Sport Pedal Covers, Sport Shift Knob, Ipod Interface, Summer Mats, Winter Mats, Cruise Control, Auto-Dim Mirror, Echo steelies with winter boots.

04-24-2012, 12:13 AM	#7
Jason@SportsCar Drives: 2015 H Production Yaris Join Date: Oct 2009 Location: Debary, FL Posts: 1,953	You should never need preload, that is only an option because those shocks were not built properly for the application. A lot of these places buy shock bodies that have a range of length that will fit a dozen or more cars and then add hardware to fit a particular application, that is the only reason they have the additional height adjustment. Sounds like you might be hitting the bump stop prematurely, or you may not have enough droop, check your travel. __________________ 2005-2008 SCCA Solo BS National Champion 2017-2018 SCCA H Prod National Champion Last edited by Jason@SportsCar; 04-24-2012 at 12:35 AM.

04-23-2012, 01:35 AM	#2
Kaotic Lazagna View User's Garage Drives: '14 GT86, '08 Vitz Join Date: Dec 2006 Location: Central Valley, CA Posts: 9,873	General rule is to never touch pre-load and adjust via shock length adjustment. Then set dampening to your liking. My friend's 8th gen Civic is much lower than my Vios (he's on BC coilovers and I'm on Tein springs/TRD dampers), and his car rides smoother than mine. http://www.rx7club.com/showthread.php?t=600868 http://legacygt.com/forums/showthrea...s-181610.html?

04-23-2012, 03:31 AM	#3
banifesto Drives: Yaris Sedan Join Date: Sep 2011 Location: Over there Posts: 11	Thx Kaotic. I did the preload adjustment as per recommended by BC. The fronts seem to be better after the adjustment. I haven't touch the rears as they are more tricky to adjust. Ride height is fine at the moment. Just that tiny bit of unsettled bounce.

04-23-2012, 03:40 AM	#4
Kaotic Lazagna View User's Garage Drives: '14 GT86, '08 Vitz Join Date: Dec 2006 Location: Central Valley, CA Posts: 9,873	NP. I'd try it the general way of adjusting coilovers. See how it works out. What's your dampening set to? Oh, and when I said BC earlier, I meant Buddy Club. haha

04-23-2012, 11:23 PM	#6
banifesto Drives: Yaris Sedan Join Date: Sep 2011 Location: Over there Posts: 11	dampers set to 8 / 5 (from soft) for fronts and rears respectively.. smooth but too soft. the installer added more preload, subtle bounce seems to be gone but it also introduced a new way kind of bounce.. hard to explain but i think the front springs are too tight lol! too much preload methinks. very contrast to the rears as they feel sharp without excessive bounce on whatever damping i put on. i'll reset the preload back to 0 (so the springs are just snug with the perches) and adjust the damping appropriately. if the subtle bounce is back, i'll just add a little preload, maybe 3mm to see if it helps. also, do coilovers need time to settle in?

04-24-2012, 10:20 PM	#8
banifesto Drives: Yaris Sedan Join Date: Sep 2011 Location: Over there Posts: 11	just redid the front springs all over again.. eased off the tension and retighten as per recommended by the tech support. bounce is nearly gone. all good now, just a matter of adjusting the damping. all DIY and the feeling is adding more preload will just increases the height.. and too much preload is bad.