Level Pinion ?

[SouthernComfort]

Ok I'm wanting to set up so my pinions are level and not pointed up.

What length links or how much longer will the lower link be over stock ?

Thanks.

[allanon1965]

change the upper ones to shorter links depending on how far you have to go. Why are you wanting them level? mine tilt upwards to help keep them from taking a beating on the rocks, the lower links help protect them when the pinion is slightly above them

[SouthernComfort]

Not a big rocker myself but will it hang up and get beat up that much more ?

[Duuuuuuuude]

I always try to keep mine aimed at the transmission.

[TacoCrawler]

Originally Posted by Duuuuuuuude

I always try to keep mine aimed at the transmission.

^ this

the only time during susp. cycle
that the drive shaft would align horizontally with the tranny output...
is at full compression and to the bump stops (shocks)

OP... what are you wanting to attempt ? why ?

Will be kinda bouncy without any remaining up travel !? Lol

[allanon1965]

Originally Posted by SouthernComfort

Not a big rocker myself but will it hang up and get beat up that much more ?

it can, even on trails, another benefit to it as duuuuuudeand and taco eluded to, is if its pointed more towards the trans output, the driveshaft angle is less and makes it easier on the joint, with the front you want to make sure you dont have the chubs pointing forward..level or slightly pointing to the rear is best for the caster angle..

[Eric0424]

Adding 6-7mm to your lower links will get you a level pinion on a stock Wraith, but this figure will change a little with your desired ride height and amount suspension travel. Optional components and/or modifications will also alter this figure. Shortening the upper links 6-7mm or a combination of both (uppers 3mm shorter, lowers 3-4mm longer) will work as well.

I don't recommend it (leveling the pinion angle) as there are no benefits to it, but that's what you'll need if you want to proceed.

You'll still have some negative caster, and you can file the slots in the C-hubs to clock them back another notch to regain some of the lost caster angle if needed. To my surprise there was no driveshaft binding at full extension. However, doing this will put your driveshaft in harms way since it will be lower than your links.

[SouthernComfort]

Originally Posted by allanon1965

is if its pointed more towards the trans output, the driveshaft angle is less and makes it easier on the joint..

But the joint at the trans is always level. No real reason other than to have both with the same angle. And for the front to have the servo level also.
But yeah I can see the rear maybe a prob hitting things.

[SouthernComfort]

Originally Posted by TacoCrawler

Will be kinda bouncy without any remaining up travel !? Lol

Not trying to compress it..

[Duuuuuuuude]

Originally Posted by SouthernComfort

But the joint at the trans is always level. No real reason other than to have both with the same angle. And for the front to have the servo level also.
But yeah I can see the rear maybe a prob hitting things.

The lesser the angle maintained, the less stress put upon the driveshaft joints.

A servo being out of level is not really an issue.

[maslin]

And the more you tip the pinion down, the greater the angle at the transfer case.

Basically, it isn't something to worry about.

[mrhobby100]

trying to setup your rig so that your pinions and servo are level make no sense to me at all. Their is no performance gain and all you will do is cause more stress with more angle on your pinion at ride height. the yeti has been known to over heat pinion bearings and cause high heat on the drive shaft its due to the angle. my buddy fixed the angle and half the heat went away got a centered axle and all the heat went away and he has his pinion pointing at the trans even though wraiths don't heat up pinion bearings as much they do wear them out quickly if the driveshaft angle is bad. I build 1:1 Baja trucks and the crazy travel that we push makes it so driveshafts have to be setup correctly or you will blow them every trip. you setup your pinion to point at your transmission with the least amount of angle on the axle pinion as possible. This will allow the most amount of travel up and down before the angles get too severe. use some VP upper links and get jato and revo rod ends and mix and match them until you get the most travel with the least angle.

[wouterb]

The benefit of having the pinion leveled is that it is in line with output shaft. This eliminates speed-up-slow-down ('unevenness' is that english?) action the joints create. (if the are mounted excactly opposit each other).
Next question is; Will the increased wear be noticable?
And, because of the different length of the links, the pinion will only be leveled in one position of the suspension.
I think it creates more problems the it solves.

[mrhobby100]

Um the slow up speed down is what your gonna create by having the pinion level and not pointed up towards the trans. Setup the driveshaft level and look from the side the cv's will be setup almost opposite and then you get the slow up slow down.

No way to set the pinion leveled and have itnpojnt towrd the output shaft. It needs to point up unless you have lowered your rig so mucb thatbthebtrans output and the pinion output are level. The pinion is always below the trans at ride height hence the pinion pointing up. Atbthe front pointing the pinion up will cause the servo to sit at an angle whcich hasnt been a problem for me for 3 years on mh wraith.

I think you are confusing leveled. You talk about leveled with the output shaft and op basically want pinion level with the ground.

[wouterb]

Originally Posted by mrhobby100

Um the slow up speed down is what your gonna create by having the pinion level and not pointed up towards the trans. Setup the driveshaft level and look from the side the cv's will be setup almost opposite and then you get the slow up slow down.

No way to set the pinion leveled and have itnpojnt towrd the output shaft. It needs to point up unless you have lowered your rig so mucb thatbthebtrans output and the pinion output are level. The pinion is always below the trans at ride height hence the pinion pointing up. Atbthe front pointing the pinion up will cause the servo to sit at an angle whcich hasnt been a problem for me for 3 years on mh wraith.

I think you are confusing leveled. You talk about leveled with the output shaft and op basically want pinion level with the ground.

No. That's not wat I mean. Even pointed towards the transmission output you'll have unevenness due to the (more or less) horizontal bend in the joint.
So unevenness in the drive shaft is inevitable.
If we assume the trans output to be constant velosity, the first joint will create unevenness in the driveshaft. This can be eliminated by having a pinion shaft in line with the output and the 2nd joint mounted exactly opposit the first one.

Offcourse this is only in one position of the suspension cycle, as the axle twists during travel.

Again: I think it is purely theoretical. Having all diffs locked will create way more mechanical stresses then the action stated above.

[Duuuuuuuude]

If this were a 1:1 I would agree, but it's not. I've always run my pinions aimed at my trans outputs and have never noticed any issues.

[TacoCrawler]

Originally Posted by Eric0424

Adding 6-7mm to your lower links will get you a level pinion on a stock Wraith, but this figure will change a little with your desired ride height and amount suspension travel. Optional components and/or modifications will also alter this figure. Shortening the upper links 6-7mm or a combination of both (uppers 3mm shorter, lowers 3-4mm longer) will work as well.

...tho' yer not completely wrong.
Your advice is not the proper procedure nor approach.

Lower link length establishes the wheel base
the Upper links establish the axle's rotation (clocking).

Altering the upper links will clock(rotate) the axle... F <-> R
and can ever so slightly extend or shorten the wheel base.
But not likely enough to cause effect unless the axle were over rotated.
And even then it would be minimal.

The same cannot be said for the lower links
as they are the primary adjustment for the WB setting.
So changing those lengths will alter the established WB.

Because Wraith's have no wheel well arches
that demand a specific wheel base...
altering that... may not be very critical.

------------

all this theory and conjecture regarding axle rotation/resistance
is mostly nonsense... and a waste of time regarding off road susp.'s

Might only be of consideration, if it were a street driven chassis
of which that suspension articulates very little.

Do ya'll theologian's even have an understanding of a Wraith
or other similar off road LT suspension systems ?

Not on road theory... off road, long travel chit.

The purpose of having a high angle universal
is to allow rotation when a drive shaft is at extreme angle.
Something that is assured... for long travel susp.'s for off road machines.

For off road LT susp. systems...
the drive shaft must be free to change from severe angle to flat
and still rotate... with as little universal bind as possible.

There is no perfect solution...
but the engineers have established a base design.
It can be tweaked a little... but just a little.

If the drive shaft's angle is too extreme...
then it's likely the suspension set up rides too tall.

There are limitations... period

Shorter shocks or raising their upper mounts
will lower the suspension to the engineered susp. limitations.

The axle's pinion angle should be directly in line
with the transmission's output at full compression...
But when it's at full droop... that won't be the case.

But too much droop - extension will cause universal bind.

So don't do that...
unless ya'll like rebuilding those universal's often.

[Eric0424]

The BIG question is: Are the CV joints at the axle pinion and transmission true CV joints?? If they are in fact Constant Velocity joints, and not just another phrase borrowed from the 1:1 world and missued by the RC industry. Then the whole pinion-angle/varied-velocity/vibration/added wear argument is moot in regards to the Wraith and anything else using the CV joints driveshafts. If they are CV joints it would also explain why the Wraith doesn't seem suffer from the troubles of uneven velocity prevalent in universal joints.

Personally I think the CVD/CVA joints we see in RC applications are a variant on the Tracta joint concept. Until I can find something closer in design to our CV joints.

The universal joint, one of the earliest means of transmitting power between two angled shafts, was invented by Gerolamo Cardano in the 16th century. The fact that it failed to maintain constant velocity during rotation was recognized by Robert Hooke in the 17th century....

Constant-velocity universal joints are articulated linkages for transmitting rotation between two (drive and driven) shafts, while maintaining a constant unit velocity ratio between the two shafts, regardless of the angle formed by the shaft axes....

[mrhobby100]

This is one of the main problems along with people not fully understanding offroad setups. They try and design the parts like 1:1 but its close not exact and long travel offroad setups have a totally different set of rules than on road setups. The first rule of thumb when setting up your rig is getting your ride height established this determines a lot. Mostly because you need to setup your suspension and drivelines to work at its optimum performance at normal ride height. Then you start your trial and error to see how extreme the suspension and drivelines can go in either direction then you limit it at that point. Offroad setups will always look crazy during the suspension cycle because some components just can't be fully long travel modified and are usually the limiting factor when building long travel. Like on a-arm setups with solidworks you can get the camber pretty good through the whole cycle but the steering tie rods and if its 4wheel drive then the front cv's will also limit the amount of useable travel. That's why you go LONG travel because by stretching things just like you learn in school math you reduce the angles at a given point the wider you go on your suspension the more travel with the least amount of angle and stress on moving parts. Also for the OP trying to setup the front axle level you want it tilted slightly and also clock your knucles to get your steering bar up as high as possible. Clocking the axle will help to give you a not so flat turn on your tires. I wont try and confuse you with the fancy terms like ackerman and scrub anti-scrub blah blah. But what you want is when your tires are turning they are sort of leaning instead of just turning flat on the tread this helps when turning on sidehills and takes some stress off the steering components because the tire has less surface on the ground creating less friction during the turning. When pointing forwards the tires will be flat but as they turn you will see a very slight lean to them.



If you setup your suspension with your drivelines inline at full compression you will be losing a lot of down travel. In offroad suspension you have to accept that you are gonna push driveline components to their max you want to setup the drivelines with the least angle at ride height because this is where your vehicvle will be most of the time while operating and especially at high speeds. you then want to go to full compression and see if you can compress your axle to where you want it and check the drive line and then adjust if need be. there will be an extreme angle on the pinion at full compression but just make sure there is no binding and the driveline can still operate freely and your good to go. then go to full droop and check if you get binding then you need to limit the travel either with shorter shock or movement of the shocks mounting position or limiting straps just depending on the direction your trying to limit suspension travel as limiting straps will only control suspension droop but not compression. It would be dope if someone came out with lil scale bump stops.

[Eric0424]

Leveling/reducing the pinion angle will raise the "steering bar". It would also increase negative caster angle, the "sort of leaning" you're referring to. Not sure how I missed it when I set the pinion angle level a couple of days ago, but decreasing pinion angle actually increased caster and brought the steering links up. Both of which could be set right (or back to factory setting) by clocking the c-hubs forward if one so chooses.