Track Tac

Right front spindle? Will

alvin l nunley said:
I’m not saying you have to change spindles. I must be extremely bad explain things.



Example; let’s say you have a 2.75° spindle. You want 3.0° camber. All you have to do is make a .25° adjustment. I would think that would be a lot easier than making a 3.0° adjustment? Has karts are built today, that means you’re also putting another 3° into the kingpin inclination. This means you’re actually changing 2 things.
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Interesting observation . Any camber adjustment will change king pin angle .
A 2* swing in camber on the right is pretty big . Factory teams may get some special spindels you never know .
As stated mass production makes comprimises for many reasons .
Additional- PRC did use a different L block when you went too the asphalt spindle on the left . Going from a 7.5 too a 5* . King pin inclination .
At that time there must have been a reason .
 
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While we are on front end geometry... What angles are the plates welded on at? If i set my kart down on a flat surface without wheels they sure arent straight up and down. Do they typically do the same angle as the block that will be used the most? I'm considering changing a junior sprint over to the gokart style would have to build my own spindles and axle.
 
95 shaw said:
It's just another way to see things.

If you look at spindle build angle instead of kingpin inclination in relation to the ground, it is easy to stay consistent with adjustments.

A spindle with 12 degree build angle and 2.5 or 3 degree camber is easily achieved without unnecessarily complex thought process. Add in caster, and in plan view, neither produces a true 15 degree kingpin inclination.
Parts are easily duplicated without difficulties you will assign to making individual pieces.

Just making things complicated, without understanding why you are making it complicated.
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I had eccentrics on our old style C front end offset.
It was easy to adjust, just spin the eccentrics, put the kingpins where you wanted, and lock it down.
I only needed to change it when he came in and said it pushed even though I didn't see it push.
I took his word for it and usually simply angled the kingpin via eccentrics top to the left of where it was leaving everything else the same.
A thumbs-up next time from the track meant I did well. ... :)

And it was before plates were around here and nobody else had a Bandit Boss with eccentrics on it. ... :)

edit: Conversation would go: Me, "I don't see it pushing"; Son, "Just take my word for it and fix the push", Me, "OK".
 
racinnut15xm said:
While we are on front end geometry... What angles are the plates welded on at? If i set my kart down on a flat surface without wheels they sure arent straight up and down. Do they typically do the same angle as the block that will be used the most? I'm considering changing a junior sprint over to the gokart style would have to build my own spindles and axle.
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This is how I would do it .
Set the L block up with the heim centered . Camber range considered .
mock it up too get the king pin angle , wanted .
Then measure the angle of mounting surface of the L block .
 
The basic design, and 50 years, or more, experimentation, have given a range to work within.

Part of this is understanding what happens at the contact patch.
Looking at any related angles without considering the effect on the contact patch creates information with no basis for use.

It does not matter which discipline (dirt/asphalt, lefty/righty, or oval), all paths to understanding must include the tire contact patch.

Spindles are designed by chassis manufacturers with their end use already in mind, based on the chassis basic design, and track profile.

Unless a spec chassis is designed, and required, the number of variables make an infinite number of possibilities available.

Still need to put the whole package together to end with a cohesive strategy for tuning.
 
Along with what Mr. shaw says .
Something just hit me.
If you change camber with the spindle , leaving the king ping the same . you affect scrub radius .
With the heim method , it appears scrub radius would stay the same .
 
flattop1 said:
Along with what Mr. shaw says .
Something just hit me.
If you change camber with the spindle , leaving the king ping the same . you affect scrub radius .
With the heim method , it appears scrub radius would stay the same .
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Close.

Scrub radius still changes as the shape of the contact patch changes.

Less negative camber makes a wider contact patch, thereby moving the center of the patch.
The inside edge of the contact patch remains the edge of the tread, or close.
For the patch to get wider requires the center to migrate away from the steer axis.
The net change, spindle build angle, vs actual kingpin inclination in relation to track surface, still necessitates a scrub radius change.
 

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As JPM says in post #10, manufacturers have probably developed things to the point of building chassis where the most common starting point of settings is in the middle of the range of adjustments they build in.

The top guns here can correct me if I'm wrong (and please do so) -- I suspect that a small camber adjustment is probably a significant "tuning" method, whereas the slight change in kingpin inclination that comes as a consequence of that is probably not an issue.

PM
 
If your setup includes 3.5° camber, that's a 33% Increase in kingpin inclination. If that's inconsequential, and I don't know if it is or isn't a, I'd be surprised.

I know my Shark kart had no kingpin inclination, And if anything, I think it handle better than any kart that I ever drove!
 
alvin l nunley said:
If your setup includes 3.5° camber, that's a 33% Increase in kingpin inclination. If that's inconsequential, and I don't know if it is or isn't a, I'd be surprised.

I know my Shark kart had no kingpin inclination, And if anything, I think it handle better than any kart that I ever drove!
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40 yrs ago, truth is you have never sat your butt in an oval specific kart chassis, thats why you stay out in left field
 
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