axle twist solution

[hemorrageman]

Yes i know this topic has been beat to death but it is a valid one.
im currently building a maxx-style crawler and ive had a thought. if you move the pumkin on your driveshaft to the right (1:1 crawlers do it to compensate for off-center engines) wouldn't it minimalize the effects of axle twist? this is just me thinking, might try it if u guys think it would work. any input would be great.

 

[TwistedCreations]

you talking about moving the diff off to one side?? why would that minimize axle twist? then you have a longer axle that would be weaker to break :neutral: but you would have to figure out what to use as a carrier bearing also.. either get some MIP CVD's or go to revos and not worry about it ;-)

 

[JakeTheAlligatorMan]

I think he's talking about torque twist/roll?

 

[hemorrageman]

actually come to think of it i might have to move it to the left :? i dont know, but in my mind if the longer side was being pushed down it would create more resistance. a good analogy would be trying to pull yourself up by your shoelaces. the pumkin will not lift itself without leverage, therefore the axle would not twist.

 

[TwistedCreations]

I think he's talking about torque twist/roll?

actually Jake, I think he may be talking to himself :?

 

[hemorrageman]

:mrgreen: im always talking to myself in one way or another

 

[hemorrageman]

you talking about moving the diff off to one side?? why would that minimize axle twist? then you have a longer axle that would be weaker to break :neutral: but you would have to figure out what to use as a carrier bearing also.. either get some MIP CVD's or go to revos and not worry about it ;-)

sorry i get confused sometimes yeah i meant torque twist

 

[JakeTheAlligatorMan]

i meant torque twist

That's a pretty good thought, I can see the Logic.

 

[cuban b]

I think the logic is flawed. Torque twist isn't the force the axle exerts on itself, it is the force the axle puts on the chassis. Moving the diff won't change that.

 

[TwistedCreations]

I hardly have any torque twist at all, but yet I run a double triangulated link setup and run my shocks in the rear just a little stiff. Torque twist is mainly in your suspension, not in the axles themselves

 

[JohnRobHolmes]

I think that moving the pumpkin would affect twist, but I think that suspension would have a greater effect overall. You would be better off making a counter-rotating tranny to cancel out twist.

 

[hemorrageman]

I think the logic is flawed. Torque twist isn't the force the axle exerts on itself, it is the force the axle puts on the chassis. Moving the diff won't change that.

the idea was to keep that one tire from lifting when throttle is applied, if the wheels were off of the ground it woudnt make a difference but on the ground i believe it would.

 

[jeepster26104]

Maybe you could run an anti sway bar that would still allow twist. You gain traction by pushing back at the ground.

 

[RCMFMaxxMan]

so your saying that moving the diff (more wieght) to the side of the axle that tends to lift under throttle? it might cut down on it a bit but not much. your best bet is tuning your suspesnion just right.

 

[TwistedCreations]

agree... with a suspension that is setup good, you should hardly have any twist at all.Maybe some, but very minimal. You would put in less work making a suspension work properly, than moving the diff to one side. The only true benefit to moving the diff to one side is for diff clearance.When that side tire goes up, the diff does also as you know.Also, that way you have less to drag in the center.But with locking out a Maxx suspension,you already have more diff clearance than a SA truck ;-)

 

[hemorrageman]

so your saying that moving the diff (more wieght) to the side of the axle that tends to lift under throttle? it might cut down on it a bit but not much. your best bet is tuning your suspesnion just right.

no nothing to do with weight, the tire that is lifting will be the closest to the pumkin and the pumpkin will not lift itself by twisting. hard to explain, but you can't lift yourself without leverage (or something to hang onto) and neither can the diff.

 

[JohnRobHolmes]

I have visualized what you are talking about many times. The only thing I cant figure out is which direction the pumpkin would needed to be moved.

I know that the rotation from the tranny causes twist on front and back axles.
I know that stiffening the oil in the rear tire opposite the lifting tire helps a lot.
Therefore, the leverage from the pumpkin on the rear tire that is "planting" should be reduced to counter torque roll. (IMO)

Now the question of which side to move the pumpkin. If the front right tire is lifting, the back left tire is planting.

the situation seems like a third class lever, so moving your effort closer to the fulcrum will decrease it's mech advantage. Moving the rear pumpkin left could be a good place to start.

 

[Reflection]

I'm with Jeremy on this one,spend less time building a correct suspention set up and your problem is solved,alot easier if you ask me. If you want to compare to 1:1,if their rigs don't handle the way they like,9 times out of 10 they'll work on their link configuration to get it nailed. They move the diff in 1:1 to suit the right or left side Tcase drop,not an off center engine and they'll put the diff right next to the wheel to gain better ground clearence.

 

[shortbusjeep]

i was just about to point out that the off center pumkin is for off center because of t case out put. i would just work on your suspension, but if you are really set on moveing your diff i would move it to the wheel the stays on the ground. put 10 pounds on the end of a yard stick hold it 3 inchs away and try to rotate your wrist, now hold it 3 feet away and try to rotate you wrist. has to do with moments. ( ya its rocket science )

sbj

 

[spookyseven]

hmm.. another idea, what would happen if you put a gear reduction on the diff so it would take less force to turn the wheels. so then you would have your driveshaft coming out of your tranny, into the gear reduction, then your reduction would turn your diff. i have no clue if this would work, just thought i would say it anyway