Change fork compression target fkc_targetnu_bv_mv_comp.xlsx  
   
c-zeta damping curve             <---- select first
fk comp target stiffness       
target x factor             <---- select second
openLevRatioFk_crz_adjust_with_import.php  
[c-zeta info]
Untitled Document
 
  • From about 4-3-19 with Blue 3391f we will shooting for:
  • bv soft x 1.03   [was 1.07]
  • mv soft x 1.08   [was 1.06]
  • for both 'a' or 'b'
 
  1. First select c-zeta damping curve  'a' or 'b'  
    • Details for curve  'a'  and   'b'  found to the right.
  2. Select fork compression target stiffness based on  'soft-aver-stiff'.
    • Increment between soft-aver-stiff is 15%.
    • Use c-zeta x factor to adjust between increments
  • Fork c-zeta 'aver' is based on soft-aver-stiff found in fkc target nu. 
  • The c-zeta curve affects bv and mv by the same percentage.   However the base valve will have the most influence on low speed and feel at 1-10 ips.  The midvalve will have the most influence on mid speed and feel at 70 ips.
Untitled Document
  • Compression zeta (c-zeta) is used to create target damping curves for both bv and mv compression force.
    • The bv and mv force is reverse engineered from the curve, then 2 lbs of target drag is added. 
    • This =  co wogas [target].
  • There are currently three c-zeta damping curves.  We simply call them  'a',  'b',  'c'.  
  • Curve  'a' (blue) is from (3253)f 4CS fork. This fork works extremely well.
    • 'a'  is softer than 'b' from 3-60ips, crosses over about 70ips then amps up more as velocities increase. 
    • This is due to the 20mm mv piston and small mv ports.
  • Curve  'b'  (red) is from (2151)f KYB forks.
    • 'b'  is stiffer at 3-60ips, then the comp force drops off as velocities increase.
    • This is because the KYB fork has larger mv piston with larger mv ports.
  probably 4CS only   KYB
ips bv aver a x 1.0 mv aver a x 1.0   bv aver b x 1.0 mv aver b x 1.0
3 2 .1   2.8 .1
10/20 5.6 2.2   6.9 3
70 16.7 19.4   16.6 19.5
100 20.9 35.2   20.2 32.2
150 28 62   26 53
400 66 195  

57

 158
  • Here is another look at curves  'a' and  'b'.
    • This compares  soft 'a'  vs  aver 'b'.
    • They start about the same at 1-2ips, then blue curve 'a' is softer and it will eventually catch and pass red curve 'b' at about 120ips.