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Wildcat Rear Suspension Design

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    Posted: Dec/02/2011 at 12:23am
Going to assume most of the crowd here is familiar with Arctic Cats new side-x-side (UTV or whatever you call these things) released a little while ago. It features a 5-link rear suspension with some very intriguing claims. I finally found a good set of pics here http://blog.utvguide.net/2011/10/arctic-cat-wildcat-5-link-rear.html and http://utvguide.net/arctic_cat_wildcat.htm. There's allot of pics so I won't post them here. Let's here your thoughts on this. What is this suspension accomplishing? Pros, cons, you know the good, bad and ugly. 

So looking at the pics there's a few instances of single shear which I know makes many of us cringe but it's adequate and works. I'm personally a bit intrigued by their joints, they look like some sort of sealed spherical bearing. The joints on the trailing links are especially interesting, looks like a decent way to get a tough and strong joint with a couple degrees of freedom. 
I wish I could see a better pic of the knuckle. I'm not sure how the trailing links are attached. Anyway, looking at the overall arrangement the camber links look almost parallel thus not much camber gain, but the camber links are slightly unequal length so there is a bit. Which leads to a lot of scrub, however those are some long camber links so that helps reduce scrub. Should help reduce axle plunge too. The trailing links look like they're producing some anti squat. One thing I'm not sure what to think about is the extra camber and trailing link. I know the extra camber link could be used to set up geometry for roll steer but I highly doubt this suspension develops any roll steer. Maybe it's just to further constrain the motion and/or take up lateral loading??? I'm not sure what's up with the extra trailing link above large one either. It could be used to set up the anti's but they look about parallel so I'm not sure about that either.

Edit: with the outboard brakes that extra trailing link might be needed just to react on the braking torque.


Edited by schooter - Dec/09/2011 at 9:20pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Nick914 Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 2:09am
For seeing it in a show:
Trailing links are attached with some sort of U-joints at the frame and with spherical joints at the wheel. All side-links use rod-ends at both ends. Rod ends in the wheel are not much sealed and the biggest one even looks like it's made to trap sand... So I think it would wear out pretty quick and bad so too bad your super "no-scrub/no camber gain/ no anything" should turn bad.
Trailing links are needed to prevent roll around the wheel axis.
Since I saw it at the show, I've been laughing a lot... with other guys of the team
Just my opinion.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote schooter Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 9:32am
Those are spherical joints on the trailing links at the knuckle?......uh then like you said they would need two trailing links just to prevent rotation about that axis. Surprised that the rod ends aren't sealed. Granted I haven't seen the Wildcat in person yet so I can only estimate what the wheel motion does but it looks like it's achieving characteristics similar to a 3-link suspension. So this is beginning to look a bit unnecessarily complex. I believe there are reasons to use a 5-link setup (roll steer, improved control on anti-squat and lift....) but it doesn't seem like this is setup to actually benefit from those reasons. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jeiB Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 9:34am
Originally posted by schooter schooter wrote:


I know the extra camber link could be used to set up geometry for roll steer but I highly doubt this suspension develops any roll steer. Maybe it's just to further constrain the motion and/or take up lateral loading??? I'm not sure what's up with the extra trailing link above large one either. It could be used to set up the anti's but they look about parallel so I'm not sure about that either.


Well, to make a 5-link suspension, you need 5 links! Your Baja (Iowa State) had a double wishbone suspension with a toe link last year, correct? If you divide each wishbone into two links, you have all the neccessary constraints.



I don't see any rodends...seems to be only sphericals with the "ujoints" in the frame mounts of the trailing links.

Originally posted by Nick914<span style=font-weight: bold;></span><span id=userPro11680 =msgSidePro title=View Drop Down></span> Nick914 wrote:


bad so too bad your super "no-scrub/no camber gain/ no anything" should turn bad.


Do you mean that you expect the lack of camber/scrub to make the car handle bad?

My question is what are the benefits of the 5link over the 3link in an offroad setting other than marketing? Is all that control over your toe/camber that neccessary compared to the extra cost from all the joints?

Also...that single shear shock is scary, Im sure it works and has been analysed but...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote schooter Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 9:47am
Originally posted by jeiB jeiB wrote:


Well, to make a 5-link suspension, you need 5 links! Your Baja (Iowa State) had a double wishbone suspension with a toe link last year, correct? If you divide each wishbone into two links, you have all the neccessary constraints.


Hearing that the joints on the trailing links at the knuckle are sphericals then, yep, they would need that extra camber link just to fully constrain the movement. 

Our rear suspension built last year was not a double wishbone. It featured 2 camber links, 1 trailing link and 1 toe link. The trick in our suspension last year was in the trailing link joint at the knuckle which introduce an additional degree of freedom that allowed for roll steer.


Edited by schooter - Dec/02/2011 at 9:48am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jeiB Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 10:28am
Originally posted by schooter schooter wrote:

Originally posted by jeiB jeiB wrote:


Well, to make a 5-link suspension, you need 5 links! Your Baja (Iowa State) had a double wishbone suspension with a toe link last year, correct? If you divide each wishbone into two links, you have all the neccessary constraints.


Hearing that the joints on the trailing links at the knuckle are sphericals then, yep, they would need that extra camber link just to fully constrain the movement. 

Our rear suspension built last year was not a double wishbone. It featured 2 camber links, 1 trailing link and 1 toe link. The trick in our suspension last year was in the trailing link joint at the knuckle which introduce an additional degree of freedom that allowed for roll steer.


OHH...I just went back to relook at your suspension. From the pictures I posted on the rear steering thread (http://forums.bajasae.net/forum/four-wheel-steering_topic780_post11508.html?KW=#11508), it looked that the trailing link was in fact WELDED to the top camber link (bad picture angle). I understand my confusion and how your setup works. The trailing link is welded to the upright, correct?

EDIT: So you had a 3-link suspension with toe link similar to TTU...I don't understand how I got confused, I'm pretty now that you mentioned that before...




Edited by jeiB - Dec/02/2011 at 10:33am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Nick914 Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 11:35am
@jeiB: by "should turn bad" I mean that once everything wears out, it should turn loose and then your wheel path won't be what it should anymore... I did not check but someone told me that the wheels were already loose because of the links...
5-link are for better wheel path they say. Over 18" of travel, they could not have a 3-link that would have no camber/toe change and scrub.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jeiB Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 11:56am
Originally posted by Nick914 Nick914 wrote:

@jeiB: by "should turn bad" I mean that once everything wears out, it should turn loose and then your wheel path won't be what it should anymore... I did not check but someone told me that the wheels were already loose because of the links...
5-link are for better wheel path they say. Over 18" of travel, they could not have a 3-link that would have no camber/toe change and scrub.


Ah, you are talking about compliance (play in the joints). I totally agree with you, more joints means more play and wear.

The RZR 900 has a 3 link with massive travel....only 14in after googling it...

RZR 900 XP promo
http://www.youtube.com/watch?v=4El_vA4CKQ8

EDIT: go to 1min46 to see a rear suspension cam


Edited by jeiB - Dec/02/2011 at 11:58am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 1:56pm

This is what you build when you want the properties of a Live Axle with out the un-sprung mass.  Essentially an independent suspension constrained to 90% mimic a Live Axle.  Traveling 60 MPH on a hellish man made off road course devised by a demented individual you would need something exactly like this.  Completely overkill for anything else, far simpler to use a Live Axle that acts 10% independent assuming the un-sprung mass isn’t a factor because you’re not traveling fast enough.

Then again my opinion is bias.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote jeiB Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 3:08pm
Originally posted by Akron 1998 to 2004 Akron 1998 to 2004 wrote:

This is what you build when you want the properties of a Live Axle with out the un-sprung mass.  Essentially an independent suspension constrained to 90% mimic a Live Axle.  Traveling 60 MPH on a hellish man made off road course devised by a demented individual you would need something exactly like this.  Completely overkill for anything else, far simpler to use a Live Axle that acts 10% independent assuming the un-sprung mass isn’t a factor because you’re not traveling fast enough.

Then again my opinion is bias.



What are you referring to? 5link suspension or the RZR video?

In any case, how is a live axle like a 5link?

They are at complete opposite ends of the "suspension spectrum"...Independent suspension will always be more comfortable and faster in corners (I'm not taking about baja).
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 3:45pm
Originally posted by jeiB jeiB wrote:


What are you referring to? 5link suspension or the RZR video?
In any case, how is a live axle like a 5link?
 
I'm talking about the 5link.  Its like a live axle in that the movement of the tire is constrained to follow the same path and the anti-roll bar combined with the roll-steer mimic the articulation.
 
Originally posted by jeiB jeiB wrote:


They are at complete opposite ends of the "suspension spectrum"...Independent suspension will always be more comfortable and faster in corners (I'm not taking about baja).
 
The new Mustang (Live Axle) is faster than the new Camero (Independent) in corners. Comfort takes a back seat to functionality when it comes to race cars.  Trophy Trucks and Race ATVs have Live Axle.  UTVs have independent suspensions because they are purchased by weak old men with back problems.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jeiB Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 4:15pm
Originally posted by Akron 1998 to 2004 Akron 1998 to 2004 wrote:

[QUOTE=jeiB]
UTVs have independent suspensions because they are purchased by weak old men with back problems.


That is because they raced ATV's or live axle cars when they were young and now they are paying the price...

Why are you obssessed with live axle and solid axle suspension?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ErikHardy Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 4:22pm
Here we go again...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote schooter Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 4:43pm
........focus!!!!!Angry Let's not ruin this thread. Actually was a decent discussion going on. 

To bring this back on topic. With this 5-link arrangement I feel you'd be just as well off with a well designed 3-link. I could easily be missing something in the geometry but it just seems that this 5-link doesn't take advantage of the potential geometry that could be setup. Seems like there is freedom on so many axis with different orientations that they had to throw more links at it just to keep it constrained.

Would be nice to have someone point out something we're missing with this 5-link......
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jeiB Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 5:07pm
Originally posted by schooter schooter wrote:

To bring this back on topic. With this 5-link arrangement I feel you'd be just as well off with a well designed 3-link. I could easily be missing something in the geometry but it just seems that this 5-link doesn't take advantage of the potential geometry that could be setup. Seems like there is freedom on so many axis with different orientations that they had to throw more links at it just to keep it constrained.

Would be nice to have someone point out something we're missing with this 5-link......


Well, I agree that a well designed 3 link will probably be very similar to a 5link in OFFROAD conditions. Onroad, the 5 link wins, no doubt.

Well...actually, if we are comparing 3link with a toe link to a 5link then I agree that the 2 setups are so close to each other, I wouldn't know how to differentiate.

Maybe manufacturing and serviceability? Easier to replace a link than to replace a trailing link with upright?

To me, it seems like a marketing scheme. Like you said, the camber is zero throughout the travel as well as the toe (I suspect)...wait, wouldn't a trailing simply fit the requirements here....

so confused now
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 5:16pm
Originally posted by jeiB jeiB wrote:

Why are you obssessed with live axle and solid axle suspension?
 
Almost entirely selfish childish reasons.  Make you a better Engineer bla bla bla………Mostly I’m just bored.
 
I would use IRS on a formula car.  Its important to remember that the most complicated solution isn’t always the right choice, and that the majority can be wrong. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 5:22pm
Originally posted by jeiB jeiB wrote:


To me, it seems like a marketing scheme. Like you said, the camber is zero throughout the travel as well as the toe (I suspect)...wait, wouldn't a trailing simply fit the requirements here....

so confused now
 
I think that was what I was trying to say.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote schooter Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 6:07pm
Found a good article from Honda discussing the advantages of a 5-link suspension. Check it out if you're curious.

http://world.honda.com/news/1997/t970702b.html
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ErikHardy Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 7:24pm
Originally posted by schooter schooter wrote:


 I could easily be missing something in the geometry but it just seems that this 5-link doesn't take advantage of the potential geometry that could be setup. 
What potential geometry are you referring to?

18" of travel is a shampooton of travel for that trackwidth. As mentioned before a 3 link would have excessive toe changes at the upper/lower limits of the suspension. At 12inches of travel, our toe change (3 link) gets rather excessive. An additional toe link would be nice but I don't think its worth the added cost and complexity.

I might be missing something but with that trackwidth and 18" of travel a 5 link is there only acceptable solution. Why they chose 18" might be the real question, seems a bit much for that vehicle. Marketing? Maybe. The new Cruze has a Watts link, I'm still pondering about that one.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote schooter Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 9:58pm
The geometry I'm referring to is the geometry that a 5-link suspension arranged into a Watt linkage can produce. Like Nick mentioned, a Watt linkage constrains the movement of a wheel to a nearly straight line versus an arc which a 3-link suspension move a wheel through. So you can in affect setup a rake angle. Additionally since spherical joints are being used with the Wildcat there probably isn't any intended compliance and with the overall arrangement, there doesn't seem to be any roll steer. After reading the Honda article. The Watt linkage style suspension also allows the links to absorb lateral and longitudinal forces leaving just vertical forces left for the shocks. So you can more precisely tune the ride characteristics resulting from the shocks. The Wildcat 5-link doesn't appear to be setup to benefit from these like a Watt linkage does.

Personally as long as you could avoid interference and range of movement issues I don't see why a 3-link style suspension like the RZR uses couldn't produce camber, scrub, plunge similar to the Wildcat. Even similar toe change assuming the Wildcat 5-link doesn't produce intended roll steer.


Edited by schooter - Dec/02/2011 at 10:03pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Nick914 Quote  Post ReplyReply Direct Link To This Post Posted: Dec/02/2011 at 11:05pm
Originally posted by ErikHardy ErikHardy wrote:

 As mentioned before a 3 link would have excessive toe changes at the upper/lower limits of the suspension.

Since their links are very long (much longer than what you'll find on baja car), I think they could have acceptable geometries, maybe just not as easily.

As for marketing reasons, it works, most people around were impressed...

One thing I forgot to mention: finishing quality is impressively bad (to me). Welds are awful, doors are loose, tubes under the engine are not capped (nice for picking up dirt and rust). The look is cool though.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ErikHardy Quote  Post ReplyReply Direct Link To This Post Posted: Dec/03/2011 at 1:28am
The links can't be much longer than what our car has along with many other teams. Granted our car is 60" wide and the wildcat is 64". The close coupled mounting inboard is similar to many other 3 links in baja. I really don't see a 3 link happening with the wildcats trackwidth and suspension travel. Could be wrong though

I've only been on a Razr on relatively flat ground but is 18" excessive for UTVs in various conditions?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote otto Quote  Post ReplyReply Direct Link To This Post Posted: Dec/03/2011 at 9:13pm
Originally posted by Nick914 Nick914 wrote:

Originally posted by ErikHardy ErikHardy wrote:

 As mentioned before a 3 link would have excessive toe changes at the upper/lower limits of the suspension.

Since their links are very long (much longer than what you'll find on baja car), I think they could have acceptable geometries, maybe just not as easily.

As for marketing reasons, it works, most people around were impressed...

One thing I forgot to mention: finishing quality is impressively bad (to me). Welds are awful, doors are loose, tubes under the engine are not capped (nice for picking up dirt and rust). The look is cool though.


First thing i noticed was the uncapped tubes in the pics and the poor welds

Anyhow, 5 link is advantageous over the 3 link because you are forced into a side view instant center right where your trailing link pivot is (with a 3 link).  This has implications with caster change in travel and can affect how the vehicle pitches under acceleration and whoops etc.  The 5 link affords designers more flexibility because less geometrical compromises must be made.

18 inches is a lot of suspension travel.  The dakar guys are limited to 10.  The wildcat does look like it goes straight very well.  Some of the photos of it in cornering look pretty bad from the front (very little camber change in travel on the front suspension).  Looks fun to drive, and wow these UTVs weigh a TON


Edited by otto - Dec/03/2011 at 9:14pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote CLReedy21 Quote  Post ReplyReply Direct Link To This Post Posted: Dec/04/2011 at 1:00am
90" wheelbase...really???

We're running similar widths with 2/3 that wheelbase and I still think we could lose an inch or two between the axles.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote schooter Quote  Post ReplyReply Direct Link To This Post Posted: Dec/04/2011 at 4:25pm
Originally posted by otto otto wrote:


Anyhow, 5 link is advantageous over the 3 link because you are forced into a side view instant center right where your trailing link pivot is (with a 3 link).  This has implications with caster change in travel and can affect how the vehicle pitches under acceleration and whoops etc.  The 5 link affords designers more flexibility because less geometrical compromises must be made.

Strategically placing the IC you're referring to is exactly what I was talking about with the potential geometry that this 5-link could benefit from. Since the trailing links seem to be about parallel the IC is at infinity. Thus (assuming the IC is indeed at infinity) the angle of either trailing link relative to a line drawn between the center of the hubs is what determines the anti-squat characteristics. So this is a special case where the anti-squat characteristics act like a 3-link.

I'll be interested to see the changes/refinements that happen to this suspension next year.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Dec/05/2011 at 12:09pm
Originally posted by otto otto wrote:

The wildcat does look like it goes straight very well.  Some of the photos of it in cornering look pretty bad from the front (very little camber change in travel on the front suspension).  Looks fun to drive, and wow these UTVs weigh a TON
 
The front suspension is just fine.  You don't want the tire camber to change when the suspension is compressed with that much travel.  When the wheels are turned for steering the camber is dynamically changed due to the pro-dive / caster angle such that both front tires lean into a turn.  Not many of you guys figure that out because its not covered in formula design books and your king pin angle is so large you negate the positive effects of the pro-dive / caster angle or worse your tires dynamically camber out of the turn due to your excessive king pin angle.  Scrub radius is not the devil, it provides some valuable driver feedback forces.  
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Post Options Post Options   Thanks (0) Thanks(0)   Quote otto Quote  Post ReplyReply Direct Link To This Post Posted: Dec/05/2011 at 10:48pm
Originally posted by Akron 1998 to 2004 Akron 1998 to 2004 wrote:

Originally posted by otto otto wrote:

The wildcat does look like it goes straight very well.  Some of the photos of it in cornering look pretty bad from the front (very little camber change in travel on the front suspension).  Looks fun to drive, and wow these UTVs weigh a TON
 
The front suspension is just fine.  You don't want the tire camber to change when the suspension is compressed with that much travel.  When the wheels are turned for steering the camber is dynamically changed due to the pro-dive / caster angle such that both front tires lean into a turn.  Not many of you guys figure that out because its not covered in formula design books and your king pin angle is so large you negate the positive effects of the pro-dive / caster angle or worse your tires dynamically camber out of the turn due to your excessive king pin angle.  Scrub radius is not the devil, it provides some valuable driver feedback forces.  


We've always made use of caster angle to generate enough wheel camber during cornering.  Pro dive and caster angle are not the same thing (unless you make the side view control arm angle equal to caster angle, in other words the kingpin axis is perpendicular to your a arms, which are parallel).  I wasn't talking about scrub, but that mainly gives steering feedback for road surface irregularities (obstacles and such) as well as from braking with tires on two different surfaces.  Mechanical trail is what gives steering feedback during cornering, which is when you want to know what is happening with the tires.

schooter: Wheelpaths for 5 link and 3 link (trailing link, what have you) are very much different, which is all I was trying to hit on.  18 inches of travel with a trailing link would start to arc pretty bad at the travel limits
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Post Options Post Options   Thanks (0) Thanks(0)   Quote schooter Quote  Post ReplyReply Direct Link To This Post Posted: Dec/06/2011 at 12:23am
Originally posted by otto otto wrote:

schooter: Wheelpaths for 5 link and 3 link (trailing link, what have you) are very much different, which is all I was trying to hit on.  18 inches of travel with a trailing link would start to arc pretty bad at the travel limits


Agreed 100% (didnt disagree before), I'm just posting my thoughts because its one of the things I do when I need a break from ProE

Edited by schooter - Dec/06/2011 at 12:23am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Dec/06/2011 at 6:20pm
Originally posted by otto otto wrote:


We've always made use of caster angle to generate enough wheel camber during cornering.  Pro dive and caster angle are not the same thing (unless you make the side view control arm angle equal to caster angle, in other words the kingpin axis is perpendicular to your a arms, which are parallel). 
 
Pro Dive dynamically affects Caster, Caster dynamically affects Camber, doing my best to be informative yet brief, and you seem to know what you're doing.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote p.lewis Quote  Post ReplyReply Direct Link To This Post Posted: Dec/15/2011 at 5:17pm
Originally posted by Akron 1998 to 2004 Akron 1998 to 2004 wrote:

Pro Dive dynamically affects Caster, Caster dynamically affects Camber, doing my best to be informative yet brief, and you seem to know what you're doing.
... just to make sure I understand what you're saying... PITCH motion of the chassis from dive rotates the kingpin axis (i.e. affects caster). And if your wheels aren't pointed straight forward, caster and camber interact.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Dec/16/2011 at 2:01pm
Originally posted by p.lewis p.lewis wrote:

Originally posted by Akron 1998 to 2004 Akron 1998 to 2004 wrote:

Pro Dive dynamically affects Caster, Caster dynamically affects Camber, doing my best to be informative yet brief, and you seem to know what you're doing.
... just to make sure I understand what you're saying... PITCH motion of the chassis from dive rotates the kingpin axis (i.e. affects caster). And if your wheels aren't pointed straight forward, caster and camber interact.
There is a lot of different ways a suspension will move simultaneously if you do/don't desire it to.  In that comment I was thinking about a Pro Dive configuration that causes Caster to change with suspension compression due to upper and lower linkages not traveling in a parallel path (which most baja cars don't bother with because that level of complexity isn't required for what your doing).   The suspension compression I'm thinking about is due to chassis ROLL in a turn.
 
Yes all you really need is for decelerating or accelerating to PITCH the chassis and Caster is affected but ROLL is more important while steady state turning.
 
 This is really starting to get complicated; I simply suggest you guys run a larger Caster angle than Kingpin angle and you will be rewarded with better Camber in a turn.
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