Caster, Camber, Toe - 850 Spider

lezesig1

expatriot
In continuation of "Just a quick Brake Job..... (and not to hijack that thread)", and response to boxy02.
Regarding ALIGNMENT

A few snapshots when dialing in this kart.

Tool.jpg

Tool. Rudimentary. Worked well. Repeatable.


Rotate_Plate.jpg

24 x 12 ceramic tiles. True enough.

Caster_Out.jpg

15 degree layout. Two sides. Caster swing-out.

Camber_Zero.jpg

Camber zero'ing.
Note: diagonal was sufficient.

Camber_Measure.jpg

Caster input, plus Camber measure - typical tool orient.

Shims.jpg


Shim stackup. Various thicknesses.

Toe.jpg


Toe setup.


Results:

Arrived at +9 degrees caster left and right. + 1 degree camber left and right. Opted for 1/4 inch total toe-in.

Rear unloaded + 1 degree camber.
Rear unloaded 0 - 1/16 total toe-in.

Please don't ask how many times the wheels came off to allow re-shimming (smile).

Did not use all slotted shims, instead got proficient enough to swap shims in 5 minutes. Wheel on,
wheel off. Gotta admit a total stack of all slotted shims would have made it slightly easier. The steel flat washers
to within a couple of thousandths surface profile made great shimstock.

One tip. Keep a light jack under the spring end held tight before releasing the arm from the chassis mounts.
This prevents the spring from sagging a few inches and having to jack it up every time to remount the bar.


lezesig
'72 850spi
 
In continuation of "Just a quick Brake Job..... (and not to hijack that thread)", and response to boxy02.
Regarding ALIGNMENT

A few snapshots when dialing in this kart.

View attachment 64798
Tool. Rudimentary. Worked well. Repeatable.


View attachment 64799
24 x 12 ceramic tiles. True enough.

View attachment 64800
15 degree layout. Two sides. Caster swing-out.

View attachment 64802
Camber zero'ing.
Note: diagonal was sufficient.

View attachment 64801
Caster input, plus Camber measure - typical tool orient.

View attachment 64803

Shim stackup. Various thicknesses.

View attachment 64804

Toe setup.


Results:

Arrived at +9 degrees caster left and right. + 1 degree camber left and right. Opted for 1/4 inch total toe-in.

Rear unloaded + 1 degree camber.
Rear unloaded 0 - 1/16 total toe-in.

Please don't ask how many times the wheels came off to allow re-shimming (smile).

Did not use all slotted shims, instead got proficient enough to swap shims in 5 minutes. Wheel on,
wheel off. Gotta admit a total stack of all slotted shims would have made it slightly easier. The steel flat washers
to within a couple of thousandths surface profile made great shimstock.

One tip. Keep a light jack under the spring end held tight before releasing the arm from the chassis mounts.
This prevents the spring from sagging a few inches and having to jack it up every time to remount the bar.


lezesig
'72 850spi
Nicely done. I hope to be at that stage soon.
 
In continuation of "Just a quick Brake Job..... (and not to hijack that thread)", and response to boxy02.
Regarding ALIGNMENT

A few snapshots when dialing in this kart.

View attachment 64798
Tool. Rudimentary. Worked well. Repeatable.


View attachment 64799
24 x 12 ceramic tiles. True enough.

View attachment 64800
15 degree layout. Two sides. Caster swing-out.

View attachment 64802
Camber zero'ing.
Note: diagonal was sufficient.

View attachment 64801
Caster input, plus Camber measure - typical tool orient.

View attachment 64803

Shim stackup. Various thicknesses.

View attachment 64804

Toe setup.


Results:

Arrived at +9 degrees caster left and right. + 1 degree camber left and right. Opted for 1/4 inch total toe-in.

Rear unloaded + 1 degree camber.
Rear unloaded 0 - 1/16 total toe-in.

Please don't ask how many times the wheels came off to allow re-shimming (smile).

Did not use all slotted shims, instead got proficient enough to swap shims in 5 minutes. Wheel on,
wheel off. Gotta admit a total stack of all slotted shims would have made it slightly easier. The steel flat washers
to within a couple of thousandths surface profile made great shimstock.

One tip. Keep a light jack under the spring end held tight before releasing the arm from the chassis mounts.
This prevents the spring from sagging a few inches and having to jack it up every time to remount the bar.


lezesig
'72 850spi
Lezesig, brilliant!! So many great ideas and thanks for reporting all your results! Will do this soon (after I renew all my bushings).
Mike
 
I did mine with the wheels off with a homemade kit. Ball bearings on the base.

ramona300


I like. I see the geometry. Measuring off the face of the disk.
As you are painfully aware of no doubt...increasing-decreasing shim thickness does not necessarily directly translate into an anticipated angle change. On a perfect machine probably. On our sheet metal to stud, to forged piece, to rubber, to bushing.....NO.

You solved the "wheel on wheel off" dilemma (smile)

Your surface plate. Formica laminate ?
 
The surface plate is Formica. This is from when I raised the upper arms pivot point by about 30mm and widened the track at the same time so I was virtually starting from scratch. I also altered the castor to 9 degrees. The "professional" wheel alignment people had it at 6 degrees! I simply copied the bracket from a Youtube video. Most of the adjusting was done on the lower wishbone spherical ball joints. The hub is at the normal ride height but without the wheel in the way, it's fairly easy to make adjustments.
 
I did mine with the wheels off with a homemade kit. Ball bearings on the base.View attachment 64805

I've taken inspiration from @ramona300 . Apologies for the blatant plagiarism:

IMG_4070.jpeg


I repurposed stock wheel spacers and a-arm pivot shafts. Fantastic idea, thanks for the inspiration. I also use this to load the suspension and easily tighten all the bolts in the loaded position. Best part about this fixture is that I can use it on my X1/9 as well!
 
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