In this video, Todd Muller at Lowbrow Customs shows you how to install the Burly lowering kit for 39mm narrow glide forks, as found on Harley-Davidson XL Sportsters and some model FXD Dynas. Additionally, Todd goes through the easy installation of the Lowbrow Tapered Fork Legs for 39mm front ends.
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You can read a full transcription of this video below:
Todd from Lowbrow Customs and this video tech tip, I'm going to show you how to lower your 39mm front forks with this Burly kit, that we sell in our web store and we're also going to show you how to install a set of these Lowbrow Customs Tapered Fork Lowers that replace the stock lower legs on your 39mm front forks. Here's the burly kit, springs and stuff to replace in there and we're also going to use this new kit that we're stocking from James gaskets.
That basically comes with everything you need to do the job here. We're going to basically be removing the fork legs from the trees. This can be-- we just have a front end off of a bike here for demonstration purposes, but the same will apply on your motorcycle. First thing you should do before - we're going to be removing the legs off of the bike - but the first thing you should do is loosen the top caps with it still the pinch bolts tightened.
It's much easier to loosen the top caps when they're still in the fork on the bike. Yes then we're going to loosen these two pinch bolts here, top and bottom, that'll let us remove the leg on the entire fork, tube and lower leg. That's why we do one side at a time if you're on the bike. This is what the fork tube will look like removed from the motorcycle.
Okay we got the fork leg off the bike, probably best thing to do first would be to remove this chrome cap, you notice there's a slot on the lower leg that'll allow you to use a punch, remove that. Next thing we're going to do is we're going to remove-- there's a bolt down inside the end of the lower leg that holds the damper tube. In order to get that out we're going to use this six millimeter allen.
I like to use an impact on it, it makes it come out a lot easier. Go ahead and take that out, and we're also going to have a bunch of fork oil in there, and then if you just pump the leg up and down a couple of times. See how the fork oil's coming out where we just took that screw out. At this stage we could take the top cap off which we loosen before we remove the fork from the triple trees, makes it easier to loosen it and this is going to be under spring pressure here.
Next thing we're going to do is we're going to take this seal off the top and reveal the snap ring underneath. Now once you get that removed, there's a snap ring in the groove. Take your screw driver, actually we can remove the spring at this stage of the game too, snap ring out. Now we're going to use kind of a slide hammer action. We've got the screw out of the bottom, snap ring out of the top and it removes the lower leg revealing the seal.
Now we're going to take the old seal off, we're going to take the spacer off because we have a new one from the kit. Now's a good time to inspect the two bushings that ride up and down inside the lower leg, these slider bushings, those look like there still serviceable. Going to remove our damper tube and here's our stock spring, clean this off a little bit and also inspect these two plastic seals at the bottom.
Occasionally I've taken this apart and found one of those split in two and there is a cut on it for installing them, but if it's broken in two pieces you might want to replace those. The kit comes with a metal spacer and a new damper tube spring. If you're going to lower your forks one inch, you're going to remove the stock spring. You're going to add the metal spacer first and then the new spring from the kit.
That configuration right there will lower it one inch. We're going for two inch so you're not going to use the metal spacer from the kit, you're going to use the stock spring and also the new spring from the kit. Go ahead and drop these back down in, comes out the other end like so. Then from the new kit we're going to put the spacer on first. It has a flat side and a rounded side, you want the flat side down and we're going to put our new seal on and be careful the orientation on the seal.
That's going to be the bottom side of the seal right there, that's going to go down. It's probably not a bad idea to take a little bit of fresh new fork oil, and just kind of coat the inside of that lip. Help to slide this over this without damaging it, the spring in there. There we go, slide that down til it contacts that spacer. Now we're ready to put the-- oh wait we have one other thing to do here.
You need the damper tube screw that goes through the bottom of the lower leg. You're going to remove the sealing washer from that, we have a new one from the kit. Just want to clean this off real good, a little elbow grease doesn't hurt anybody, and then we're going to put the new seal from the kit. It also has kind of a flat side around this side, you want the flat side to face in, okay that's ready for installation.
Then we're going to grab our new lower leg here. When you take these out of the box they're going to have a bolt in the bottom, pitch bolt. You want to remove that, so we can gain access to the hole to get the damper tubes screw in there.
It's probably not a bad idea to maybe just put a little bit of fork oil on this too, and we're just going to slide this together. Start your seal by hand, bottom that tube down to there so the damper tube will be all the way at the bottom of here. Then we can install the screw into the bottom. It's okay to just hand-tighten that for now because it's much easier to put the final torque to it with the spring pressure pushing down against that. The next thing we're going to do is, we're going to use the seal driver tool, motion Pro, sold on the website.
Now the nice thing about this tool is it does have this ring, if you spin this around, you can take it apart, we're not going to need it apart for the way we're doing the job here today. Let's just say you were putting a set of chrome lower legs on your bike, you can install the legs with the lower legs onto the fork tubes with everything still attached to the motorcycle. This will allow you to put this over this because you're triple trees up here and you can't slide it down over that.
For demonstration purposes here, we're just going to put that back together because we're going to use it like this if you've got your fork off of your bike. This is going to send that seal home, like so, revealing the snap ring groove. Make sure that seal is below that. We're going to put our new snap ring in making certain that it is completely seated in the groove, screwdriver helps that go down in there. Give it a visual, make sure it's all the way down and that's that, now the snap ring is in there.
Now we're going to put this other dust shield on there, that protects the bearing. I'm sorry D seal now looks like it's going in with just finger pressure, it's all the way on the one side. You can use a soft hammer to send it home and on the left, there we have it okay. Then we're going to install our spring next, this is the new spring from the kit. I generally like to put the tightly-wound side down.
Next thing you do is determine the amount of preload you want on the spring. It's best to refer to the instructions that come with the lowering kit. It does come with the plastic PVC pipe that you can cut to size. What you're going to do is you're going to put your cap up and you're going to measure how much it's pushing the spring down, that will determine how much preload you have on the spring.
Since I'm using different blowers on here, I can plainly see that by the amount of that's coming up out of there, that I don't need to put a piece in there freer with a stock lower leg stock tube. You're probably going to need to refer to the instructions that come with the kit to determine the preload. It also says something to the effect of for a heavier or lighter rider you could change that specification.
Alright, now that we've got the assembly all the way together, it's time to put the fork oil in. I have this handy tool here it's called a ratio rate, it's good for measuring fork wall and other various fluids maybe you guys with two strokes might recognize this. The capacity on these legs is going to be 10 ounces, you're going to go to the fluid ounces and you're just going to fill this up to the 10 spot, actually 10.2, a little bit clinging to the container. We're just going to go right about there, okay.
You can fill this up before you put the spring in or after. I actually have this funnel that I made up where you can just stick that down in there and fill up the fork well, okay. Once you've got it all reassembled, time to put the top cap back on. While you're at it, we have some really great choices for replacing your stock cap, as you can see this one was buggered up from whoever worked on this bike before me.
We have these flush mount ones, also good for the guys with 48 bikes for changing handlebars. They're going to sit even with the surface of the top three, they're available in black, they're also available in aluminum and they're also available in brass. Now we also have another option for you here, these are a fairly new product here at lowbrow, these are called our radius 4 caps. Those are going to stick up a little bit on the top, a little nice little turn into the stock ones, available in chrome or black.
We also have a matching center cap for those that will log go here on your tree, okay. For the demonstration, I'm going to use one of the new low profile black ones. Sometimes it can be challenging to get this cap on there. [silence] We help if we're going the right direction. Okay, get started on there, since again that can be fully tightened once the fork is on the bike. Then once you fill up your fork tighten your cap, be sure don't forget to tighten the one we just hand tighten here.
It's okay to use your impact there is a torque spec on it but if you just hit it once with your impact a little bit once you've got the cap on that's putting some pressure on the spring. Then you're ready to reinstall the forks onto your motorcycle. When you put them back in your trees be sure to follow the torque spec of the manual, for torquing the four pinch bolts, and also there's an installed height spec on the top of the tube, how much it sticks up out of the top tree.
There's just a real simple measurement, but you want those two forks to be even in the tree side-to-side. The lower fork leg kit that we have also comes with a special axle that's designed specifically for these fork legs and once you've got your axle in there one side one thread and this is designed for three-quarter inch bearings.
This is going to slide through and the end is a little bit larger. You can hold one side of the wrench while you tighten the other side, and then you have the two pinch bolts but that does come with the new fork legs.
That's it. Happy fork lowering guys.