As I told awk earlier, the distance from the inner pivot point to the shock mounting pivot point is not the only figure needed to make the lower mount the right shape.
You need the distance from the inner pivot point and the distance above a straight line drawn between the two pivot points. This is not the way to figure out maximum/minimum position and to maximize shock travel vs suspension travel... simply the measurements needed to properly mount a predetermined shock to a predetermined control arm for a predetermined amount of arm travel.
In this case, I have the measurements for stock suspension (which can be used safely for most any shocks but won't net the maximum suspension travel) and what I welded my arms to to get 8 1/2" of travel.
If you have the arms built and have everything in place, you can install the lower ball joint (leave two threads exposed) and hold a ruler up to the side of the arm to "draw" a line between the pivot tube and the pivot point inside the ball joint.
Measure up from the ruler 1 1/4" and remember that general area. Then measure out from the center of the pivot tube 6 1/2". Once you've got an idea of where the pivot bolt should be, you may want to cut some carbboard out to make a jig for the design of the "ears" that sandwich the shock. Once you have the general shape, you can work on the spacing.
I have the figures written down for the cross bar distance and length away from the pivot tube.
The cross bar needs to be notched at the same angles up against the front and back tubes to sit parallel to the pivot tubes. The length from the center of the notch to the center of the notch is 4 1/2". A side note, the HF tubing notcher won't do 4 1/2" without modification. I'll post that with pictures tomorrow...
Once the cross tube is cut to length, it slides down in between the front and back tubes for a snug fit. Once you have a cardboard cutout of the center of the shock pivot bolt, you can cut the cardboard cutout to match the cross tube until it fits together matching the measurements and then cut some of the .125" plate out to match the cross tube with a hole drilled in it at the location marked by the measurements. Those measurements should put the cross tube just slightly inside but almost directly under the shock lower mount at maximum shock extension and then slightly outside but almost directly under the shock lower mount at minimum extension.
Alright, got all that? good go make some arms!
You need the distance from the inner pivot point and the distance above a straight line drawn between the two pivot points. This is not the way to figure out maximum/minimum position and to maximize shock travel vs suspension travel... simply the measurements needed to properly mount a predetermined shock to a predetermined control arm for a predetermined amount of arm travel.
In this case, I have the measurements for stock suspension (which can be used safely for most any shocks but won't net the maximum suspension travel) and what I welded my arms to to get 8 1/2" of travel.
If you have the arms built and have everything in place, you can install the lower ball joint (leave two threads exposed) and hold a ruler up to the side of the arm to "draw" a line between the pivot tube and the pivot point inside the ball joint.
Measure up from the ruler 1 1/4" and remember that general area. Then measure out from the center of the pivot tube 6 1/2". Once you've got an idea of where the pivot bolt should be, you may want to cut some carbboard out to make a jig for the design of the "ears" that sandwich the shock. Once you have the general shape, you can work on the spacing.
I have the figures written down for the cross bar distance and length away from the pivot tube.
The cross bar needs to be notched at the same angles up against the front and back tubes to sit parallel to the pivot tubes. The length from the center of the notch to the center of the notch is 4 1/2". A side note, the HF tubing notcher won't do 4 1/2" without modification. I'll post that with pictures tomorrow...
Once the cross tube is cut to length, it slides down in between the front and back tubes for a snug fit. Once you have a cardboard cutout of the center of the shock pivot bolt, you can cut the cardboard cutout to match the cross tube until it fits together matching the measurements and then cut some of the .125" plate out to match the cross tube with a hole drilled in it at the location marked by the measurements. Those measurements should put the cross tube just slightly inside but almost directly under the shock lower mount at maximum shock extension and then slightly outside but almost directly under the shock lower mount at minimum extension.
Alright, got all that? good go make some arms!