According to RaceTech's website, For a Hawk GT and rider who is 155 lbs wihthout gear.
<p>
Note that the only thing that changes is the spring rate?  I put in some other rider weights (100 to 280 lbs)<br>
and <b>still</b> the only thing that changed was the spring rate.  Hrm...  That sounds weird to me.
<p>
<table border=1>
<tr>
<th><th>oil weight<th>oil height<th>spring rate<th>spring preload<th>emulator preload
<tr><td bgcolor=pink >street, all skill levels
<tr><td align=center>prefers soft<td align=center rowspan=8>US-2&nbsp;/&nbsp; 10 wt.<td align=center rowspan=8>160mm<td align=center rowspan=2>0.823 kg/mm<td align=center rowspan=8>20mm<td align=center rowspan=8>2.0
<tr><td>standard stiffness
<tr><td>prefers stiff<td align=center>0.843 kg/mm

<tr><td bgcolor=pink>road race, all skill levels
<tr><td>prefers soft<td rowspan=2>0.888 kg/mm
<tr><td>standard stiffness
<tr><td>prefers stiff<td>0.908 kg/mm
</table>