Official Baja SAE Forums Homepage
Forum Home Forum Home > General > Design Discussion
  New Posts New Posts RSS Feed - Compression and rebound valving
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Compression and rebound valving

 Post Reply Post Reply
Author
Message
himanshunandarshi View Drop Down
Double Secret Probation
Double Secret Probation
Avatar

Joined: Nov/24/2016
Location: India
Status: Offline
Points: 5
Post Options Post Options   Thanks (0) Thanks(0)   Quote himanshunandarshi Quote  Post ReplyReply Direct Link To This Post Topic: Compression and rebound valving
    Posted: Sep/08/2018 at 7:44am
I was curious to know what valving do teams here use?
Most of the teams in India have a certain fear of revalving their shocks. My team did it a few years ago but we couldn't validate the effect of the valving and it was a total fluke that we got right.
Also, to the teams using Afco shocks, what compression valving do you guys use and why? I couldn't find any method other than subjective tuning over the years.
Back to Top
sujandinesh View Drop Down
Baja Godfather
Baja Godfather
Avatar

Joined: Dec/27/2013
Location: Eindhoven
Status: Offline
Points: 413
Post Options Post Options   Thanks (0) Thanks(0)   Quote sujandinesh Quote  Post ReplyReply Direct Link To This Post Posted: Sep/10/2018 at 12:51pm
Valving which shock? What make? Based on my little experience of tuning the shock, I can tell you that a lot would depend on the make of the shock other than of course the basic concept of tuning. 

The best way you can validate anything with the shock is using a shock dyno which I believe is a bit challenging to find, at least in India. 
RVCE BAJA: 2011-2015
General Motors: 2015-2016
Tyre Testing - University Racing Eindhoven: 2016-2017
Tyre Dynamics - TASS International: 2017-2018

Tyre Engineer - Apollo Vredestein
The Netherlands
Back to Top
himanshunandarshi View Drop Down
Double Secret Probation
Double Secret Probation
Avatar

Joined: Nov/24/2016
Location: India
Status: Offline
Points: 5
Post Options Post Options   Thanks (0) Thanks(0)   Quote himanshunandarshi Quote  Post ReplyReply Direct Link To This Post Posted: Sep/10/2018 at 1:56pm
It's a monotube Afco shock 3/6 rebound and an 8 in travel. I did suffer from harsh bottom outs that caused the rebound shims to flex permanently. That maybe one of the causes of having almost no rebound at all (this is my theory) but again I don't have anything to validate my hypothesis.
Is this a valid hypothesis? If it is, how do I revalve them for the given shock? (I know shock dynos are almost nonexistent in India but I don't want the revalving to be a total fluke)
Back to Top
vin2000 View Drop Down
Welding Master
Welding Master
Avatar

Joined: Sep/23/2013
Location: Bangalore,INDIA
Status: Offline
Points: 145
Post Options Post Options   Thanks (0) Thanks(0)   Quote vin2000 Quote  Post ReplyReply Direct Link To This Post Posted: Sep/11/2018 at 1:48pm
For damper tuning , a shock dyno is a must for validations. With all the quarter car models, you come up with force vs velocity graphs for the particular suspension settings. These would serve as a base for dyno trials. Changing the shim stack on both compression and rebound side will require different shim thickness and sizes till you achieve the desired graph. 
This is obviously the practical method and not the textbook method of how you do it. 
In your case , harsh bottom outs would mean compression damping issues. Try playing around with spring rates if it is a air shock. This will just be a band aid but not the solution. Nothing can be much said before putting your shock on the dyno and finding out the damping ratio. You will only find shock dyno's at damper OEM facilities in India, as these are not commercially available.
RVCE-BAJA
2011-2015
www.thrbaja.com
Back to Top
 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down



This page was generated in 0.047 seconds.