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For something fun.....A class 1 buggy weighs 3500-4000#'s. Lets say 3750 average. They usually have around 20" of wheel travel. say 40/60 weight bias and you get 1500#'s in the front. 1500/20 inches of travel=75#'s per inch. Now if your motorcycle powered car weighs 1500#'s with the same weight distribution you get 600#'s in the front /75 = 8" of travel. I could make the 1500# car handle the same with under 10" of wheel travel......... More mass needs more time to decelerate transfer the same amount of force. Wheel travel = time. The lighter the car the less wheel travel is needed. Granted, this assumes that a lot of things like unsprung weight will decrease proportionally so it's not exact but more of a fun observation.
Wow, very insightful. About 5 / 6 years ago I asked the question on another forum and got crickets. My question was is a well thought out 12" better than a poorly thought out 16" or some variation of that. My underlying concern being that so many folks had tunnel vision re: Total travel vs. Quality of Travel. You just kind of hit the nail on the head.
So I'm trying to soak this in, and seems to me that any type of suspension that has a forward arm (trailing, semi trailing, 4/5/6 link) that once that forward arm reaches level any additional up travel will result in the tire also moving toward the front of car. And if your running 30" tire and 3" ground clearance then 30"/2=15"-3"=12" so the last 12" of travel the tire would move forward. And thats a sweet example of the wheel travel vs weight.
Bit off topic but along the lines of what we're talking about, found this pdf with some interesting observations on G-forces at impact, time and the use of suspension:www.highspeedcraft.org/pdf/7Ullman_HSC_Suspension_Seat_Design.pdf
Wheel moving forward toward the chassis pivot line but back at the angle the pivots are angles up at the front. I thing the bump is at about 16 degress so if the pivots are angled up at the front more than that its still moving back.I'm working out why sometimes these ideas move more slowly than others, but I think I've got it.Next question; would the wheell moving back make that much of a difference maybe comparing it to wheel size. With the wheel moving out from the below holizontal and back at the (umm) pivot angle the combines effect from hitting a bump and the wheel moving would be a big combines rearward movement that could smooth things out.If the approach angle of a bump is 40 degrees and the initial movement of the wheel is 20 degrees back does that back the effective face of the bump 20 degrees compared to an a-arm design. This is an oldy, but a goody.