TRAILING ARM Suspension Explained with Jake Burkey - ROCK RODS TECH

what's going on everybody this is Jake Berkey from rock rods and busted knuckle films and today I want to talk to you a little bit about trailing arms now first of all if you don't know what a trailing arm system is follow me over here to the board real quick and I'll show you looking at the side profile of a vehicle this would be like a four-link system this is the pivot point at the chassis this is the pivot point at the axle normally you would see shocks mounted from the chassis down to the axle out here and what that does is it gives a similar proportion between shock travel and wheel travel or actual travel now what we can do is we can take our shocks and we can move them up the lower control arm and for every inch of travel that you get out of your shocks you're gonna get more travel out of your rear end and because you do that and because you have more shock travel all of a sudden all the big hits the whoops the rocks and everything else become cleaned out a little bit more and then you can travel a little bit faster through it so what you're essentially doing by using a trailing arm system is increasing wheel travel now let's talk about some of the things that I ran into whenever I was building my system and our new system to take care of all those issues [Music] so let's talk a little bit about our new trailing arm systems and some of the reasons why we had to build these new trailing arm systems some of the issues that I ran into whenever I was building my trailing arm systems and hopefully you can learn from that and we can pass on some of that knowledge now to our customers and I work together on this project and I couldn't be happier with the way these things came out they are just unbelievably well built and the quality is great so if you buy these things you're gonna be amazed by the way that these things come out but I want to talk to you a little bit about some of the reasons why we did the things that we did and therefore you can make an informed decision whenever you're buying yours now the trailing arm systems that you find most the time on the market are already gonna come with a length they're gonna come in a 42 or a 46 or 48 or a 52 or whatever that length is and a lot of times you're gonna have to custom build these control arms these trailing arms to your rig and so that's why we decided to make these things cut to length we built the trailing arm system so that you can trim it to whatever length that you've got basically you've got a three components you've got your outside main tube you've got your front uniball and then you've got your hind joint back here at the back there whatever you cut that length to is whatever by-god you want and I love that because I don't like being told what to do when it comes to my trailing arm length you know my bug you ended up being way long because I couldn't get everything snaked in there and when you're building your trailing arms you're probably gonna run into some similar situations so cut to length was probably one of the first things that I wanted to get addressed the second issue that we ran into whenever we were building our trailing arm systems is the manufacturers generally have the bolt hole locations already lined out for you well we didn't want that we wanted to be able to adjust our shock location for more or less travel and for clearance on the upper control arms and things like that by making a bracket system that can slide back and forth up and down the trailing arm so basically what you have is a piece of two and 3/8 inch 188 wall tubing since we've built the kit and had some real world testing we found out the fit one étoile tubing wasn't quite strong enough so since we produced the kit we've decided to go up to a 250 wall tubing we've sold a bunch of these kits and we haven't had any problems since that this bracket sits on then you can adjust this bracket forward and backwards depending on where you want your shocks mounted to give you more or less travel you got a 16 inch traveling you want about 18 20 inches you can slide it back here if you want a whole lot more travel you just slide it up here and weld it on that was a huge benefit for us because what we ran into in ours was some packaging issues and it would be it would have been very helpful to be able to mount the bolt holes into a different location just by sliding down about two inches I'd lose a little bit of travel but I'd clear the radiator and I wasn't able to do that with that last kit so I wanted to make sure that we addressed it on our [Applause] the third thing that we wanted to address on our trailing arm system was the fact that they're just not big enough they're not strong enough we keep on bending them we keep on breaking them the ones that are on my rig right now or bowed up like a boomerang so we wanted to make them super strong but also keep the weight down so the very first thing that popped into our heads was 7075 t6 aluminum we've been using this stuff on our four-link systems for a while now but we didn't really want to weld to it or bolt to it because we were afraid that it was gonna weaken it so what we decided to do was take a piece of 2-inch 7075 t6 aluminum and wrap it with a piece of two and three eighths 188 wall tubing this is just regular D um tubing this piece slides inside this piece make an absolutely super-strong combination because these two are slid inside of each other the first time you hit a rock they're gonna pinch solid and they're not going to move anywhere and this creates a whole lot of extra strength now let's move on to some of the joints some of the biggest joints on the market that we're running right now are an inch and a quarter heim joint the problem with an inch and a quarter heim joint is is it doesn't have enough articulation in the joint for a long travel suspension when you start articulate in your suspension you get binding down here at the joint if you're running a 1 inch bolt now what a lot of guys are doing is they're taking these and they're necking them down and running a three-quarter inch bolts so you can get more articulation but I've seen those 3/4 break and when they break the entire suspension comes out and it's catastrophe it's a catastrophe it tears up absolutely everything so what we decided to do was go to an inch in 3/4 yes inch and 3/4 Heim so this is an inch and a quarter Heim that is the big dog that everybody talks about this is our inch and 3/4 Haim absolutely massive but what we were able to do was go to a high misalignment spacer and still run a one-inch bolt so this takes up the problem with the binding that we were talking about earlier and still gives you a massive 1 inch bolt that you can run through another problem that we see a lot of guys haven't is they take their trailing arms I put their jam nuts on there and there nuts get loose because they over articulate and then the jam nut becomes loose when the jam nut becomes loose now your threaded part is going into your trailing arm and it's getting a little bit of wobble to it next thing you know your heim joint pulls out of the tubing and there goes your suspension once again so we decide to go with this massive pinch bolt this pinch bolt system is a lot better for holding that heim joint where it needs to be it's read it inside and it just pinches down with these two bolts right here it's a lot stronger combination up here at the front we decided to go to the massive custom-built uniball this does not exist except for on this kit and the reason that it's made like this with this stem right here is because now when you weld you can plug well on the sides and you can physically weld all the way around the top and also because it's hollow it actually has a spot that's milled out in this 7075 right here that goes in the snout so basically those two go together like that with that piece of two and 3/8 on the outside and when you weld it together it makes a solid rod that goes from the unit ball all the way down to that back heim joint that right there is a super strong combination and runs a 1-inch bolt right through the middle the fourth thing that we wanted to address when we were building this trailing arm system was anti wobble now if you don't know what anti-wobble is it's kind of this mythical creature with a big it's not I'm just kidding it's not a unicorn but it is difficult to find everybody who you're on the internet talking to thinks they know what they're talking about but then can't explain it so I'm gonna help you guys out basically what happens whenever the shock is in its suspension travel and it gets to a certain point but instead of the shock pushing down the control arm wobbles anti-wobble keeps that from happening and anti-wobble can be built in a number of different ways but before we go into that let's talk about the worst type of anti wobble or the worst type of wobble so basically what also can happen because your shocks are now mounted to the trailing arm if you have your shocks mounted at the trailing arm and you take an impact from the side your trailing arm can actually turn farther than your shocks can turn and if that happens you can actually break the eye off of your shock so anti-wobble is designed to keep those two things from happening and a lot of guys take and Bend a part of their arm down like this to be able to get anti-wobble built in because the center point from here to here is higher than where the shocks are mounted and because of that it allows that trailing arm to push straight up and down through the suspension cycle that's the way mine are right now but there's a couple problems with that one clearance if you mount this trailing arm where it's supposed to be mounted to get your anti squat where it needs to be then you have a bad clearance problem because they're hanging down so low that they rub and bash on everything so what I did was I took mine and I moved him up but what that did was it took my anti-squat values and put it way out and I didn't have enough anti-squat so if you look at the past year pretty much every time I stomp the gas it was just squatting the suspension versus propelling the vehicle forward now it's very important for your suspension to have the right number of anti squat because the problem that you run into on the East Coast is when you stomp the gas trying to get up a Ledge you need that rear-end a hooking for it to propel you forward in the problem with not having enough anti squat as you stop the gas and it squishes the suspension it doesn't allow you to go forward so with a trailing arm system like this on the East Coast specifically it's very difficult to get your anti squat values where they need to be and then if you do you have a clearance problem down here so what we decided was we were going to build our anti-wobble right up here in this front uniball and if you look we've got a unit ball right here but it's got these little Delran or polyurethane bushings I forget what they are and that keeps it from articulating too far and that is giving you just a little bit of movement if you look it's barely moving back and forth now the only way that we were able to make this work was because we designed this extremely large hind joint that we talked about just a minute ago all your suspension articulation goes into that heim joint and the only way we were able to do that was by running an inch and 3/4 using these high misalignment spacers and still keeping a 1-inch bolt so you stopped the up here at the front put all of your articulation back here at the back that keeps your shock straight and keeps your wobble down one of the biggest pet peeves I had with my trailing arm system was the fact that the shocks were mounted below the top plane of the trailing arm just like the ones that you see back here the reason I can't stand that design now is because so much mud gets accumulated inside there that now the shocks are sitting below the level and it doesn't come out every time you hit a puddle you get water inside there you get muddy slurry and it's like liquid sandpaper as the shock travels up and down it just eats the top of that shock I out next thing you know you're gonna have to replace the top of your shock eyes mine or a completely wore out just because they've been in that scenario for the last couple months now our new design is made specifically so that it barely has enough room for your shock eye to sit in there because of that there's no room for a bunch of mud there's no room for water to accumulate now your shocks are sitting there moving up and down freely without having a bunch of slurry around them to tear the shock eyes up the next thing that we wanted to do is make ours round because the ones that we currently have on there are flat on top and because they're flat they accumulate a ton of mud whenever you're out racing they slow the buggy down change the way the suspensions run and this round tubing is gonna be a lot harder for mud to stick to so the point of this video was basically to educate you on trailing arms and tell you about some of the things that I ran into whenever I was build in mine and educate you on making a sound decision when you buy your next trailing arms if you want to take a look at these trailing arms go to busted knuckle off-road comm look at our trailing arm section we have everything you need to build them this way or build whoever you want alright so I wanted to show you guys how to put all this together and basically what you have if you have an outside plate it's the one that's got riot Kevin there then you got an inside plate like that it backs up against it and you've got that for the inside and the outside you just put a bolt through there and you have to come up with some spacers I use these for shock spacers right here actually perfectly and then you put your your next piece on like that and then you put your nose one next step set it on top of your piece of tubing and install these pieces that's gonna keep these things nice and strong and also keep the dirt out [Music] all right now that's nice and tight we've got space for our welds all the way around double check to make sure that everything is down and snug where it needs to be we're going to do a couple tack welds an we're gonna come back and well everything out you so there you have it that's the first part of building this kit just welding out the bracket that the shocks set on the next thing that we're gonna do is take this piece of tubing and we're gonna cut it to length once that's done we'll slide the aluminum in slide our ends in well it all out position our shock mounts and weld all together so I've got the trailing arm laid out so that you can see exactly how long these things are and they're basically a 48 inch trailing arm but they measure out to be 48 and a half inches I wanted to leave a little bit of thread showing so I could have some adjustments so 48 in 5/8 now my trailing arms have already been built so I have to put them back in the exact same position as what I had originally in order to make the sway bar and everything mount up perfectly so I want these to be 47 inches so we're going to cut off an inch and 5/8 from the piece of steel tubing and from the aluminum use a little piece of cardboard this is actually made specifically for wrapping around pipe and marking it I cut it up a little bit smaller so it's easier to get into tight spots and you just make a mark all the way around the tubing we're gonna cut that off and we're gonna do the same thing with the piece of aluminum that goes inside okay so take your heim joint and you lay it out on the tubing exactly where you need it make your mark and then you're gonna have to cut the aluminum a little bit shorter so it butts up inside the tube so you can see where I made the mark on the steel and right there I transferred the mark over to the aluminum if you look really closely there's a step right here and that step is where that steel comes up and butts up against it that way you can get inside there and put a nice penetrating weld all the way around this thing so we thought of everything whenever we started building this kit so now we're gonna take it over a hit it with a bandsaw cut it off all the way around make sure she's true and get started on welding all right what I'm doing now is I'm just drilling a 5/8 blown hole all the way through the end when it gets down through this other side will stop and that'll give us another good spot so well we'll be able to weld the chamfer and then turn around and weld the plug hole as well I want to show you guys just how nice this kid is everything has been machined so beautifully I just want to show you something this piece right here your solid 7075 watch how this thing slides down in here I mean there is absolutely no play but it slides down beautiful then want to take this I'm gonna put it in here and you can see that it gets right about there and look at this that's amazing amazing tolerances right there all right everything went together absolutely perfect so the next thing we need to do is well but before we well we want to take this snap ring right here and pull it out of the unit ball up here at the front all it is is just a wave spring and we got to pull that wave spring and pull the univille out so and then you can take the unit ball and you can actually just press it right up and out so this is a regular old uniball milled into that housing it's a beast look at that thing [Music] [Music] check out how massive that joint is that thing is just a beast you ain't gonna break that thing look at the size of my hand just kidding that's the joint we're putting in this kit ha it's a little mini-me compared to this one inch and 3/4 straight beef one of the things that we always do whenever we're puttin these unit balls together at the front part of our trailing arm kit is we spray this PTFE spray by wd-40 directly where the race contacts the bearing if you push this thing to the side right here you can see right down inside there you've got really good access to get inside the bearing race now we like to use this stuff because it doesn't attract dirt and dust it's a dry lubricant and it's perfect for this application so before you weld the shock bracket to the trailing arm one thing that our kit is great for is being able to move this bracket forward and backwards and get the perfect spot to mount your coil overs so make sure that before you well everything together it's got good clearance on your upper control arm and everything fits now a great thing about these that I forgot to mention throughout the video is that these were actually 18 pounds lighter than the trailing arms I took off my buggy and the reason I bought the original ones is because they were supposed to be lightweight when after I got my trailing arms installed and got my anti-squat where it was supposed to be I was able to put that buggy on the podium time and time and time again as you can see behind me I want a ton of races so if you want to put your buggy on the podium you need to follow the directions in this video and check out our trailing arms because they will make your bum you have better performance if you want to see some older rock rods tech videos take a look right over here and they'll be lined up tell us what you want out of the tech videos some of the things that you want us to cover some of the topics you want to see right down below let us know about the trailing arms what you think about them and as always thanks for watching [Applause] prevalent is a good word to address when we were building this trailing arm system is anti-squat now an testicle that's how wobble

Channel: Busted Knuckle Films

Views: 294,151

Keywords: trailing arm suspension explained, trailing arm suspension, trailing arms suspension, trailing arms vs 4 link, trailing arms off road, rock rods tech tip, rock rods tech, jake burkey riot buggy, jake burkey new buggy, jake burkey racing, tmr customs, tmr customs race series, jake burkey, trailing arms, busted knuckle off road, busted knuckle off road parts, busted knuckle off road parts and accessories, riot buggy, bubba bacon, busted knuckle films, bused knuckle video

Id: bi5k4zKd1mc

Length: 22min 5sec (1325 seconds)

Published: Sat Jun 30 2018

Reddit Comments

[u/Ajnybo]

can you please stop spamming your videos here?