bouncing

[whitetrash21]

watching some sled pulling vids on youtube.... what causes the trucks to start bouncing?? some of these trucks were gettin 4-6" of air under all 4 tires!! .... that looks like it is prime time for breakin stuff....

is it the dirt?? driver tech?? truck setup?? all of it....

 

[Bluemax]

All of the above usually. The hopping usually starts with something in the driveline having flex in it, Probably the traction bars or leaf springs flexing. Or maybe to much wheelspin on a sticky track. It could be a number of things though.

But 4-6in. of air under the tires is just nuts.....

 

[whitetrash21]

yah it was a dodge.... reg cab, got out about 100 ft and started hoppin. he backed out of it, got the hopping stopped, layed into it again and the whole truck started gainin massive air.... i think they broke something because he stopped it after that. didnt try to keep runnin and you could hear people in the stands doin the "oh shit" ....

i was just curious. the trucks weren't pro or unlimiteds.... looked street trucks. no hangin weights so i was just wondering what caused all the rebound.

 

[redws6rocket]

my truck will hop if i run i class were you can not add wieght.

 

[durallymax]

If you ever start hopping, you might as well stop. YOur not going to pull out of it.

It really depends alot on track prep and driver.

 

[Whitetail Addict]

Usually on a stock truck, it is caused by axle wrap. The axle housing tries to rotate itself under the truck, turning the leaf springs into and "s" shape. That is why it is usually cured by traction bars to prevent the rotation. Just my $.02

 

[McRat]

I only had bouncing once.

Casper was about 6700lb. I had full 2500HD leafs and stock suspension all around except:

Clamps on the leafs behind the axle.
Blocked to 0" travel rear
Sleeves and Cognitos

Tires were 285 Durango A/T's, 25psi front, 50psi rear.

Hopping started within 10' of the line, I lifted at 100' due to violent hopping.

I removed the rear blocks, pulled again, and no bouncing.

 

[Distributor]

Alot of the bouncing is caused by too much air presure in the rear tires.

 

[PowerMax]

It's all about set up. Every truck reacts differently.