what causes bounce

S

smokeisfun

still learnin
Joined
Oct 14, 2007
Messages
230
just like the title says, bouncing could have cost me a $4000 transmission so i would like to know how to prevent it

you pro pullers let me know


what tires?
tire pressure?
preload on traction bars?
its an auto so what gear? i was in 2nd
 
The biggest cause I've found is power to traction ratio. More power or wheel speed, no bounce. Less traction at the same power, no bounce. Finding the happy medium is tricky part.
 
mech2161 said:
The biggest cause I've found is power to traction ratio. More power or wheel speed, no bounce. Less traction at the same power, no bounce. Finding the happy medium is tricky part.
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simply put the tire will grab traction wrinkle the sidewal then unload throwing the truck upwards and starting the the bounce

like kevin said you want a happy medium
 
I believe bouncing is caused by orange parts/paint on trucks. My truck never bounced last season, painted it orange, now it bounces like a rabbit.
 
What tire pressur u running jamie? And what are you leaving the line at? I ran BFG A/T's last year and bounced every pull coming off the line at 3600 now with truxus and coming off the line at 4K! No problem!
 
mech2161 said:
And you changed the rpm where your making power.
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mech2161 said:
Jamie you need to come out hard and let it eat.
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Thats true Kevin, I did change rpm, but if you watch the vid in my sig....I launched hard & bounced hard. I've tried hard/soft launching & nothing worked. I'm thinking tire pressure.
Kman9090 said:
What tire pressur u running jamie? And what are you leaving the line at? I ran BFG A/T's last year and bounced every pull coming off the line at 3600 now with truxus and coming off the line at 4K! No problem!
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I run my truck from a jobsite to the track, don't change anything. I run 50psi all around [tires] & launch at 4233rpm.
 
so would wide tires with little tread on them full of air help out. also how do you come out of a bounce...or once you start is the pull over.
 
smokeisfun said:
so would wide tires with little tread on them full of air help out. also how do you come out of a bounce...or once you start is the pull over.
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Most organizations have a 75ft rule. If you start bouncing, just stop & start over if you haven't crossed 75ft. If I cross the 75ft line, I usually back out, then gun it & it would come out smooth. Thats exactly what happened in the vid in my sig.
 
I'm not a puller but I see it just like a drag racer shaking the tires on a biting track or just like Kevin was talking about.

How many pro mods or 3.0 trucks do you see bounce?

Jim
 
Tire pressure is a big reason for bounce as is the flexing of single bar traction bars. Any movement of the rear axle will send a shock through the truck that will start a bounce. If you run an auto when it shifts it shocks the driveline, ie. springs, tires, frame. Any little movement by a part will cause another part to move then another ending up in a bounce. A reece hitch flexing will cause a bounce. It could be any number of things causing a bounce but only change 1 thing at a time until the problem is fixed. I personally am a video junky watching hours of video trying to fix problems on my truck.
 
Jim Fulmer said:
I'm not a puller but I see it just like a drag racer shaking the tires on a biting track or just like Kevin was talking about.

How many pro mods or 3.0 trucks do you see bounce?

Jim
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so your saying, i need more power or less traction...allrighty
 
Watching videos is the only way I figured out what my problem was.
 
DISTURBED said:
Tire pressure is a big reason for bounce as is the flexing of single bar traction bars. Any movement of the rear axle will send a shock through the truck that will start a bounce. If you run an auto when it shifts it shocks the driveline, ie. springs, tires, frame. Any little movement by a part will cause another part to move then another ending up in a bounce. A reece hitch flexing will cause a bounce. It could be any number of things causing a bounce but only change 1 thing at a time until the problem is fixed. I personally am a video junky watching hours of video trying to fix problems on my truck.
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I'm gonna try more pressure. The traction bars are set at zero preload & they are 2" DOM [1/2"] wall.
 
one other thing, since i snapped my out put shaft of my trans...would there be any reason to worry about the intermediat shaft...dave told me that there would be alot of tears shed if i broke that intermediat shaft, thats why he said to have my output be my weak link if out of everything...
 
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