Ohlins Suspension - Pistons and valves

This side with the compression wedges has the largest ports and it has to do with the fact that the shaft enters or leaves when it enters it is more difficult to push that part of the space that the oil that passes here in compression wants to occupy is already being occupied by the shaft and that is why it is different here is an Example of the difference in this dyno sheet, this is a TT x36 ILX dyno sheet that I made and this is the original valve and the bleeds are the same, it's minus 10 minus 10 and it comes with exactly the same cushioning or. same stack of wedges, compression and rebound, it's the same thing and you can see the difference.

The compression if you go out like five inches, it's one hundred and forty pounds of force, where the rebound is one hundred pounds and that's identical, everything is identical, so that shows you the difference depending on whether that axle goes in or out, in other words , if it is on compression or rebound and the TT x40 TT x 46 strut you don't have that problem if it is a dyno blade for a TT X 40 with identical

valves

on each side, the forces would be identical because there is no oil that shifts the axis, so what's next? Well, in my ILX tube video I talked about why I'm tough. above the surface of a piston always and I can explain it here there are two

pistons

of this earlier model and a later model and you notice that it has a lot of surface and it is shiny and smooth and what used to happen was from time to time At that time, yes you looked at the dyno blade, there would be a little blister and the compression site would show up and what it was was the wedge would stick for a moment until I guess I got enough force to peel it off and then it would pop open and cause this little bulge and It turns out that when you have to smooth surfaces things tend to stick, there could be different reasons, it could just be the surface tension of the oil that's under the shim or what machinists have when they have gauge blocks and they stick, it's called smoothing ability. ring, where there are actually two really smooth surfaces that stick together, it's hard to separate them and there's something called Van der Waals forces and basically when things are really smooth and really close together they exchange electrons or something and they have some kind of force weak that holds them together so I don't know exactly what it is, it could be any or all of these, but the way öhlins mitigated it later This is a nice light, it could be from a TT 44, but you notice the surfaces at the ones that the shim sticks on or the shim seals are very small and they have machined small areas that stop here to make sure there is the least amount of area in contact with the Shem and I rough them out anyway just because I'm used to it and besides, if you know you're making hundreds of

pistons

, you can't rough them all out.

Know that when they are machined, they are smooth also on older pistons, if you have older Overlands, this semicircle here, this circle around means it is the rebound side when it is not very clear, it is usually clear what the rebound cut is , the ports are much smaller, okay? This is a digressive piston. I don't use them. I don't like aggressive

valves

, but the idea with a digressive piston basically means that there is a lot of force initially and then the force levels out as the shaft speed increases. There are all kinds of reasons for this, there are supposed reasons for this which I'll get into in another video, but anyway, you can always identify a digressive piston because there's a ring around it that, unlike something like this, where the wedge seals. the ports on this, the shim is sealed by this ring and the reason is that this center part is lower than this one, so when you have an opinion on the shims, you know that they are the ones where you can change the preload, but if you press the middle of this it pushes a little bit of preload to the wedge so what happens is it takes a little more force to turn the stove on but once it opens it throws liquid out and that was my sound of liquid discharge and then the damping is bypassed. you know it did it becomes linear so anyway that's it and here are the two 36 millimeter ports to the port that was in production it looks like it's symmetrical it looks like the ports are about the same size and they don't give any indication once rebound and once compression and this was a production piston but they don't make it anymore and I really liked it, it did what I liked to do, anyway there is another two port piston, for some reason They just don't do it. use them more, so here's a really interesting piston mm-hm.

I think it's from NASCAR. It is a high frequency piston. They use them in TTX 40 and TTX thirty-six. They do not have. They do not use shims on the pistons with TTX technology. unless it's a boring office and they make a blow-off piston, but they have all the other little parts on the piston, mostly around it, and I guess when you have these clamp-on shocks, NASCAR had a height restriction right. and on the super tracks Aero was really important, they wanted to lower the car, so they use the shocks instead of for mechanical grip, they use them to pump the

suspension

by having no compression damping and there is practically no compression damping and there are tons of rebound damping. when I put one of these on my Dyna wants or these NASCAR Super Speedway shocks and it stopped via dyno, then what happens is the shock can go up or the

suspension

can go up but it can't go down because there is too much force, well, any I think with This high frequency piston has 21 small ports on each side, it is a rebound side and was 1.14 millimeters in diameter.

I did the math and here's the math and if you're a math expert let me know if I did it right but I think I did it hmm so if you add up the bleed, in other words how much, how big if it was a hole , the bleeding would be five point two. two millimeters, which is quite a lot, so what happens is even though the piston was way down on the inside, you know it was Lord, you could still flap because what happens is you have the one ring, there's a gap of three millimeters with a two a millimeter O-ring and the O-ring, depending on which side it's on, seals these little holes, so what could happen is this piston could move up and down.

You know, if I moved a little bit, it would stop moving because the O-ring would cover the ports, but then if I were to hit the other direction, I can move a little bit in either direction, so this is a high frequency piston and they have them in TT that if the speed goes up too much, it will dump oil and it doesn't go through the valves and they have a high frequency piston, there are no shims, but the little holes and the o-ring and everything, probably for Indian things, when you're going 230 miles an hour , you know, and you even have little bumps. they're probably oscillating at a very high frequency so that's what this is what a high frequency piston is okay and this is a ni x30 piston öhlins fork and then where they have compression on one side rebound in the other, this is a compression piston. the shims, this is not the right shim, it's too big, but I had it placed here, so in compression these ports are covered and have shims on top, but in rebound, see how big these ports are and this is the counterplate and there is a small spring. and there's a wedge like that with a little spring behind it so you can move away when you're going to bounce and allow the rebound side to do all the damping and not get in the way of that and now we're going to talk about valves and I'm going to start with this, This valve, this is this, this particular shock is a wcj, it was the Nascar shock.

I think NASCAR still uses them. I know they used them in 2002, Tom, when Tony Stewart won the championship with öhlins. on these WC J's means Winston Cup whatever and they only allowed it to have one adjustment, so they had a piston bleed on the other side, but they wanted to meet it, some of them want to do more and they want to do. more on compression and metering and as we saw this is pretty much the same as that ILX TTX 360 ilex, there is a separator piston that goes in here and at the top there is nitrogen, but the oil goes down and what they did was that There are different bleeders you can get for this and shims and I don't remember which direction it goes in but basically it goes in there and then the tube comes on and that way when the shaft displaces the displaced oil they can measure it and do things. just like you do with a remote reservoir that they weren't allowed to have, but it's really hard to take the shock apart and do it, so they would buy pallets full of these shocks and valve them differently and if they like it they're at Talladega, the one they worked on the last time they were there, they would hang them up and have some new ones and yeah, you know, it's a lot of work, competing is a lot of work, especially at that level.

Anyway, this is another type of valve. Okay, these are the TTX valves, some of them and these are the valve holders or I don't know what you want to call them. This is where you make your adjustments. This one is two way. This is the shape I prefer and these are the different valves. This is the standard linear valve which I really like. Now we know that it is a digressive valve that I remove. I can't find any use in the forum. There may be more below. way, I don't know and then this is the fancy one that comes on some of them and if you look on the back of this one, that ring is the check valve that allows the oil to flow to the other side, like you're in compression . and this is the bounce side, it has to flow to the other side and on this one the ports for verification seem a little small, there are more ports here and there are some other differences.

I could never get this to do exactly what I wanted it to do. which doesn't mean much, exactly what I wanted it to do, but maybe someone else can use it and what happens is you put the wedges here. This is a bleed around the piston that is measured by the needle valve to see how much bypass there is. This one has the same thing but it also has another mechanism that is not like that? There are a lot of little things missing here, but it basically does it effectively, but it also has a way to preload the shim stack for high speed, so anyway.

That's it, and then here's how it works: you put shims here and then this continues here and there's a spring that pushes this against the shims that are in the valve body, which you can maybe see in my video on how to turn the ILX. Well, that's all I know, so that's it, I hope it wasn't too boring. I try to keep them short, but there's a lot of information and it wasn't just a fraction of the information, but it's a good introduction. the fact that there are differences, so remember to authorize everything in service and sales, quick response in service, compete with any legitimate price in sales, subscribe and hit the bell I guess, and next time I'll work on a video on The leggings may take a while, but I'm working on it, thanks again, bye.