Good idea, I’ll check it out
Very true lol
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Why is the axle so far forward that it literally overhangs the top bushing slightly?
That’s going to put a lot more forces on the front pair of bushings than the back pair.
It seems odd to make that decision, but also have the same duro bushing for the front kingpin and the back.
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Relative to the picture below, moving the axles down and left will give more rake basically (more dive), up and right will reduce rake (more stable), Apex PKP are more centered between the pins and more inline with the plane of the bushing seat so they will do better at speed but Trampa will have more wiggle wiggle wiggle
Moving along the plane of the bushing seat will affect leverage in the turns while offset from that plane will affect leverage in the straights based on my intuition of mechanics
Hypothetically if the pins are actually parallel you can swap the orientation of the hanger to affect the performance. Backwards will give a more linear dive while upside down will make a strong return to center at neutral
Edit: wait no I fucked up, the taller the board is the more dive it will have, so upside down hanger means strong return to center at neutral lean, backwards means it will carve more
Trampa PKP should feel pretty wiggly in the straights but push you out of the turns, which is kinda gross. I think the Apex Airs will be more stable
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If we look at the truck this way, so I can describe the axes easier, moving the axle up/down increases or decreases rake.
But moving it forwards and backwards doesn’t at all. It just changes the axle position relative to the bolt pattern, the load on the different bushings, and when mounted at an angle on a deck will change the ride height.
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Ride height does affect it, but its akin to drop mounting vs top mounting (higher ride height will make it harder to stay at neutral and lower ride height makes it easier to stay at neutral)
But farther from the baseplate is more rake and closer to the baseplate is negative rake
Edit: if you mount the hanger backwards it will also make the axle center to center shorter which means smaller turning radius, but not by much
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what if one was to have negative rake in the back and positive in the front then compensated with wheel size?
If the axle is beyond the intersection of the outside pin and the bushing seat then the load on the inside pin pulls away from the baseplate, gross
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You could keep the wheel size, if you flip and invert the rear hanger then it will have negative rake, shorter wheel base, and more return to center…will feel like split angle baseplates
You might need a bit more angle on the deck to get it to line up perfectly actually, back will sit a little low
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you could then swap a xl kingpin and a gigantic barrel RS top kingpin maybe.
You’d be better off compensating with risers first before wheel size.
Negative rake reduces the ride height a lot, and in terms of truck geometry when we talk about ride hight what we really care about is where that puts the roll axis. Risers will increase the height to the roll axis, but bigger wheels will not.
Actually, I just built a board where I tried having a too low roll height in the rear only. I was hoping to add stability to the rear but keep control through higher topmount leverage in the front, but it didn’t work like I hoped.
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because roll axis defined where deck(standing platform) height compares to the axle pivot or axle location given rake from hanger. Do I have it well defined now?
Witness this artful technical drawing
Run short board side and tall road side bushings in the front with the axle out and up, run tall board side and short road side bushings with the axle in and down on the back
Should have an even ride height but a more stable rear end
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Yes, more or less.
To completely break it down, if you draw a line for the pivot axis and a vertical line off the axle, the roll center of the truck is where those lines cross.
The roll axis is the line connecting the roll center between the two trucks.
And the roll height would be the distance between the top of the foot platform, and the line making up the roll axis.
Here’s my little diagram
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I’m slightly confused which lines correspond to what there, can you elaborate?
Also isn’t the roll axis the normal projection of the axis on the pivot plane?
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Its not the best diagram, because it just throwing labels on a sketch I already had.
You know what, maybe?
Its been a while since I did the working out.
Yes, according to what I said, the roll center would be the pink arrow.
The normal projection would be the green arrow?
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Normal projection would be green, but I’m too tired to figure it out lol
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Same, but I think you’re right.
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I want to just make a model in cad but SW is being a bitch because of the school VPN
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