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Old 02-13-2008, 08:25 PM
  #25142  
Darkseid
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Originally Posted by seaball
so, guess the chart is easy, now.

shims vs. toe

0.00mm = 3.8*
0.5mm = 3.2*
1.0mm = 2.6*
1.5mm = 2.0*
2.0mm = 1.4*
2.5mm = 0.8*
3.0mm = 0.2*

now raise your hand if you just skipped to the bottom. (and we can do some extra credit at the next big race).
Raises hand...


Originally Posted by seaball
math. i can make a chart, but here's the math. (don't be scared, it's about 8th grade level, maybe )

the holes for the vertical screws in our pivot blocks are 48mm apart (roughly), and that's where the 'pivot' for inboard toe is. that length is the hypotenuse. the difference in shims (f/r) is the opposite side (of a triangle). opposite over hypotenuse = sin(x). so x = invsin(shims/48). (use your calculator)

eg: 2mm/48mm = .0417. invsin(.0417) = 2.39* (approximately, 2.4*). therefore (as stated in the back of the manual). each millimeter of inboard toe is equal to 1.2* (or i think they wrote that each 0.5mm = 0.6*)

for the rear end, we reverse the blocks, so you can't just count up the front shims and divide. the reversed blocks appeared to give a 3.2mm (.125") offset (when i measured the hingepin at the front and rear). therefore arcsin (3.2/48) = 3.8*

so the unshimmed rear has 3.8* of toe per side, and every half millimeter shim used at the front blocks removes 0.6*.

that was all measured (and based on my memory from last may). maybe 'ca' can read the prints and give us some better numbers.

- yvonne durkowski -
Hey...hey.........HEY...........you just keep your math out of my hobby!
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