Go Back  R/C Tech Forums > General Forums > Nitro Off-Road
shock pre-loading >

shock pre-loading

shock pre-loading

Old 09-28-2008, 01:36 PM
  #1  
Tech Master
Thread Starter
 
jrwoodchuck's Avatar
 
Join Date: Nov 2007
Location: Northampton, Massachusettes
Posts: 1,336
Default shock rebound!!! oops,,

I mean rebound!!
After reading some threads, I saw people talking about when they do it and when not to, and I understand. But my question is. How do you build the shocks to get the amount of rebound that you want.

Last edited by jrwoodchuck; 09-28-2008 at 08:24 PM.
jrwoodchuck is offline  
Old 09-28-2008, 01:47 PM
  #2  
Tech Elite
iTrader: (11)
 
jamminnay's Avatar
 
Join Date: Apr 2008
Location: IL
Posts: 2,021
Trader Rating: 11 (100%+)
Default

you can adjust it by how much oil u push out when bleeding... i typically run very little rebound..
jamminnay is offline  
Old 09-28-2008, 01:47 PM
  #3  
Tech Adept
iTrader: (7)
 
Join Date: Jul 2008
Location: Lexington, Kentucky
Posts: 155
Trader Rating: 7 (100%+)
Default

? huh
maximuspowell is offline  
Old 09-28-2008, 02:23 PM
  #4  
Tech Master
Thread Starter
 
jrwoodchuck's Avatar
 
Join Date: Nov 2007
Location: Northampton, Massachusettes
Posts: 1,336
Default

So you push more oil out to get less rebound?
jrwoodchuck is offline  
Old 09-28-2008, 02:35 PM
  #5  
Tech Elite
iTrader: (11)
 
jamminnay's Avatar
 
Join Date: Apr 2008
Location: IL
Posts: 2,021
Trader Rating: 11 (100%+)
Default

correct.. and leave more oil in for more rebound.. you need to be very precise making sure they are all the same.
jamminnay is offline  
Old 09-28-2008, 02:51 PM
  #6  
Tech Addict
iTrader: (1)
 
boostfiend's Avatar
 
Join Date: Dec 2006
Location: Selah WA
Posts: 543
Trader Rating: 1 (100%+)
Default

If you download this....

http://www.teamxray.com/teamxray/sho...p?file_id=4455

and look at page 32, there is a step by step for alternate rebounds.
boostfiend is offline  
Old 09-28-2008, 03:01 PM
  #7  
Tech Elite
iTrader: (28)
 
Join Date: Oct 2004
Location: Michigan
Posts: 3,356
Trader Rating: 28 (100%+)
Default

Originally Posted by jrwoodchuck View Post
After reading some threads, I saw people talking about when they do it and when not to, and I understand. But my question is. How do you build the shocks to get the amount of preload that you want.
Preload would be adjusting your spring collars or clips to lower or raise the cars ride height. What you are talking about is the rebound of the shock.
jbrow1 is offline  
Old 09-28-2008, 08:21 PM
  #8  
Tech Master
Thread Starter
 
jrwoodchuck's Avatar
 
Join Date: Nov 2007
Location: Northampton, Massachusettes
Posts: 1,336
Default

Originally Posted by jbrow1 View Post
Preload would be adjusting your spring collars or clips to lower or raise the cars ride height. What you are talking about is the rebound of the shock.

Man you're right. Glad you knew what I ment and not what I wrote. I know how to adjust pre-load, it's rebound that I was courious about.
jrwoodchuck is offline  
Old 09-28-2008, 08:26 PM
  #9  
Tech Adept
iTrader: (7)
 
Join Date: Jul 2008
Location: Lexington, Kentucky
Posts: 155
Trader Rating: 7 (100%+)
Default

so what's better 50% rebound or 100% rebound. Also what do you do if the rebound is noticeably different?
maximuspowell is offline  
Old 09-28-2008, 08:50 PM
  #10  
Tech Master
Thread Starter
 
jrwoodchuck's Avatar
 
Join Date: Nov 2007
Location: Northampton, Massachusettes
Posts: 1,336
Default

Originally Posted by boostfiend View Post
If you download this....

http://www.teamxray.com/teamxray/sho...p?file_id=4455

and look at page 32, there is a step by step for alternate rebounds.
thanks, that works!
jrwoodchuck is offline  
Old 09-28-2008, 08:55 PM
  #11  
Tech Elite
iTrader: (2)
 
PTP Racing's Avatar
 
Join Date: May 2003
Posts: 2,701
Trader Rating: 2 (100%+)
Default

Its all about the amount of compression behind the bladder in a shock. As the shaft enters into the bore of the shock it displaces oil. Because of this building the shocks with the shaft in different amounts will yeild different amounts of rebound. I usually build mine with 100% rebound per the Xray manual (shaft all the way out) but have done some experimenting with less. In very rough conditions it may be better to have less rebound so the buggy can react to the bumps quicker without letting the rebound act as a stiffer spring. I feel a shock with more rebound has a more progressive feel and is less likely to bottom out over big jumps. My thinking is building with 100% rebound is easier for me to duplicate even rebound from one shock to the other and if I need better bump handling I will adjust my shock oil accordingly.
PTP Racing is offline  
Old 09-29-2008, 11:09 PM
  #12  
Tech Regular
iTrader: (1)
 
Join Date: Dec 2006
Posts: 366
Trader Rating: 1 (100%+)
Default

Compression and rebound can only be adjusted in r/c shocks by changing
shock fluid. The rebound rate will always be the same as the compression
rate. In automotive type shocks there is a compression stroke check valve
that increases the compression stoke rate going up and relieves the rebound
stoke going down. Therefore increasing traction by keeping the wheels on the
ground. Maybe one day R/C cars will get this type of shock.
topcat-lll is offline  
Old 09-30-2008, 03:31 AM
  #13  
Tech Regular
 
lowey79's Avatar
 
Join Date: Dec 2007
Posts: 356
Default

Originally Posted by topcat-lll View Post
Compression and rebound can only be adjusted in r/c shocks by changing
shock fluid. The rebound rate will always be the same as the compression
rate. In automotive type shocks there is a compression stroke check valve
that increases the compression stoke rate going up and relieves the rebound
stoke going down. Therefore increasing traction by keeping the wheels on the
ground. Maybe one day R/C cars will get this type of shock.
What you're saying is correct, but "rebound" when refering to rc shocks is how far the shock shaft extends after compressing it. This is due to the oil that the shaft displaces when compressed.
lowey79 is offline  
Old 09-30-2008, 05:25 AM
  #14  
Tech Regular
 
bjr48's Avatar
 
Join Date: Apr 2008
Posts: 274
Default

Originally Posted by jrwoodchuck View Post
thanks, that works!
+2
I am always playing with taking a drop or two of fluid out of the shocks to play with rebound. Not that I knew how much rebound I might want but always knew all shocks should be equal. This method allows you to set how much you want by where you place the piston during filling. VERY nice.
Also saved me from buying new driveshafts. I didn't know the pins could be pressed out and replaced! And didn't know that the next step after your pins get flat was for the drive cups to start getting trashed. I already "recycled" the pins from a bent front axle to rebuild my center diff to front driveshaft good as new and will order some Hudy pins over the winter to fix the rest! Easy stuff.
I saved the manual as there are quite a few tips in there that Kyosho never gave me
Now if I just knew how much rebound I want. I'm guessing 100% from the later comments. Our track is relatively smooth and I bottom out bad so it should help some along with some other changes I plan to make for next year.


Does setting up for 100% rebound put tons of extra pressure inside the shock body and cause any side effects?
bjr48 is offline  
Old 09-30-2008, 07:52 AM
  #15  
Tech Master
iTrader: (8)
 
Akhor's Avatar
 
Join Date: Feb 2008
Location: Alberta,Canada
Posts: 1,386
Trader Rating: 8 (100%+)
Default

Originally Posted by bjr48 View Post
+2
II didn't know the pins could be pressed out and replaced! And didn't know that the next step after your pins get flat was for the drive cups to start getting trashed.

Can you do this with any drive shaft or only the 808?
Akhor is offline  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.