Basic bump load value?
Basic bump load value?
(OP)
I am looking for basic bump (G) value - If I would use, say 3g at the wheel - what effect does dampening have on a object mounted to the chassis/body - would this mean that 3G would be to high a value?
- which opens up the question a bit to... if bump is the highest value then use this value to envelope for all directions or is there a better way of looking at the loading of an item that is along for the ride.
I wish to build a hitch mounted carrier for a bike. I could buy one of course - but where is the fun in that.
- which opens up the question a bit to... if bump is the highest value then use this value to envelope for all directions or is there a better way of looking at the loading of an item that is along for the ride.
I wish to build a hitch mounted carrier for a bike. I could buy one of course - but where is the fun in that.





RE: Basic bump load value?
Norm
RE: Basic bump load value?
Therefore you (and the sprung mass of the car) actually see less than 1g dynamically in bump
BUT
better safe than sorry. I personally would overdesign this by a fair bit, mountain bikes spread all over the road are embarrassing and expensive.
Cheers
Greg Locock
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RE: Basic bump load value?
You've also got vehicle pitch to worry about as the vehicle traverses bumps one axle at a time (maybe someone here has a typical pitch value for a passenger car); which may cause more than 1g acceleration on the end of your lever arm (bike rack) protruding from the rear of the vehicle.
A safety factor of 4 on the load sounds reasonable to me, if you're a decent welder.