Full suspension trike design and build.

With double wishbones the lower arms are always longer than the top. This is to tilt the top inwards as it compresses. This is needed because as you turn hard the outside wheel takes more weight and the suspension is compressed at that side. The chassis has leaned meaning the top and bottom inner pivots have changed their relationship to each other. Getting the top to come inwards works to keep the tyre vertical despite that change in the inner pivots. By making the top even shorter in relation to the bottom you will then introduce negative camber to the outer wheel as it leans in a turn. This puts the wheel at a better angle to the road to avoid the tyre rolling around the rim or worst case being rolled completely off it. Go too far with shortening the top one and the tops of the outer tyre can start to want your leg space depending on the overall track and amount of lock.
 
No that will make that your wheel will hang over in a corner. Making the bottom one longer makes that it stays upright
sorry... I mean make the arms the same size but increase the width of the bottom attmenent points OK I see now I needed to see the difference

same length


Bottom longer



I understand it. I have another question

Why not a McPherson strut... It simplifies the design. I mean it doesnt look as cool and you cant dial in the camber sure... but how fast is everyone planning on going? is this for a race trike?? just for looks? I mean you guys can't be going that hard around corners. I have made some hard turns on my dad's catrike 700.
 
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sorry... I mean make the arms the same size but increase the width of the bottom attmenent points OK I see now I needed to see the difference

same length


Bottom longer



I understand it. I have another question

Why not a McPherson strut... It simplifies the design. I mean it doesnt look as cool and you cant dial in the camber sure... but how fast is everyone planning on going? is this for a race trike?? just for looks? I mean you guys can't be going that hard around corners. I have made some hard turns on my dad's catrike 700.

You answer it yourself. Also it isn't that hard to make. My quad has the same system and it works great.
 
I was looking a grade 9.. I thought was the stuff you are supposed to use for structural
Grade 2 is the one I opt for for home-welding.
Grade 9 is comparable to grade 5, but with better malability, both Alpha-Beta alloys, stronger than the Grade 2.
But not weldable without a transition to Alpha phase around the welds, making those brittle.
 
Grade 2 is the one I opt for for home-welding.
Grade 9 is comparable to grade 5, but with better malability, both Alpha-Beta alloys, stronger than the Grade 2.
But not weldable without a transition to Alpha phase around the welds, making those brittle.
Well... I need to design a bike then think about welding AL... Which means I need a proper tig... or I can just steel myself. And do steel frame because a tig welder is pricey and I got a stick buzz box. My nasa certed welder I go to for welding retired.
 
Well... I need to design a bike then think about welding AL... Which means I need a proper tig... or I can just steel myself. And do steel frame because a tig welder is pricey and I got a stick buzz box. My nasa certed welder I go to for welding retired.
That's a pity. But as Brad -our leader- shows, even an old buzzbox can do well.
 
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