Why is Ohlins so good? A must read before buying the best suspension
OHLINS shocks Explained
Ohlins has been the dominating suspension brand for Moto GP and many other major races around the world. They proved themselves by breaking track records and for most riders, Ohlins is gonna be the first brand pops up in their head when thinking about replace the suspensions. “The yellow spring makes you faster!”, they say. But what do you have to know before purchase with your hard earning cash? In this article, we will show you different types of suspensions that made by Ohlins and how to choose the one that suits your riding style the most.
After reading this article, you will be able to:
-identify different types of Ohlins shocks
-tell what adjustability simply by the SKU code
-have a better understanding of the rear shock functions
What is Ohlins?
Ohlins is a top-notch suspension brand that has been gaining recognition not only in world class racing, but also in amateur race and, more recently, in car races. Ohlins is based in Sweden, a Scandinavian country that many rally drivers born, and perhaps the slippery roads of Sweden is the secret behind its excellent performance. The company was founded in 1978, but was not well-known to the world until mid-80’s. At that time, there were almost no articles about world championship motocross, and there was no way to know what kind of suspension was installed on the champion machines.
However, the situation changed drastically when photos of the suspensions used by the leading teams in MotoGP (WGP at that time) started to appear. The performance of these suspensions quickly made them a major player, and they became an indispensable suspension brand for high-performance custom bikes. In the early 1990s, Ohlins’ yellow springs were already many riders that dying for. The excellent performance earned many respect to the brand Ohlins.
Why shall I replace my shocks?
It’s probably one of the most expensive custom parts that you can put on your bike and making that decision ain’t easy, but let me explain to you why they worth your money.
Trust me when I say that you will be shocked by the production quality of these shocks. Not only by the beautiful finish, but also how precise of their quality control is. Normal riders may not notice this, but when you work at company like Webike and you open 3 boxes of Ohlins shocks, compare them side by side, it’s crazy that they look completely identical. Most custom parts would have permissible errors but Ohlins just don’t have them. Aside from the that, the quality of what’s inside is also being kept at the highest level. Someone may argue that “It’s a machine cut so it can make exactly same production all the time!”, sorry dude, you are wrong. It’s a lot harder to achieve Ohlins level than you might think. Ohlins doesn’t want to just make a beautiful spec sheet for people to see, even if a part does not appear in the specifications, if it’s necessary for performance, Ohlins will not cut corners.
Nowadays, there are many suspension brands that have top level precision, but in some respects this is simply due to the improved precision of machining. However, Ohlins has been known of its outstanding precision since the time when other companies’ precision was still crappy, and its history of high precision is one step ahead of the rest of the world. Their experience in the field of high precision is unparalleled.
You don’t have to ride on one with Ohlins to understand. For example: if you remove the spring and push in the damper rod, the gas pressure inside the rod pushes it back out. That’s true for all the stock shocks, other brands’ shocks. and Ohlins. However, while the stock damper rod does not fully return to its original position due to various sliding resistances, the return time is different each time, and the position where the extension stops is different each time, the Ohlins damper rod always fully extends. Moreover, the time from full flexion to the end of extension is exactly the same every time. How amazing is that?
Wide adjustment range
The adjustable range is wide, as a comparison, other brands that claim to have multi-step adjustment may have little or no change in how the shock reacts, but this is not the case with Ohlins. 20 clicks is 20 clicks, nothing more, nothing less.
Fine adjustment range
Every click matters when you setting up an Ohlins shock. This can only be done with the precisely produced production and technical know-how’s. The image is as shown in the figure below.
Ohlins suspensions are known for their durability, you can’t find any unnecessary rubbing or rattling on Ohlins because they are precisely crafted, therefore the durability is superb. Their suspensions also allow trained mechanic to over haul, so they will last quite a few decade, might last longer than the bike. Personally (Editor: the author, Makoto Kadowaki, another awesome and knowledgeful person working at Webike) I bought my first Ohlins 30 years ago and they are still in use. The spongy dust cover and bump stop rubber next to the bearing in the mounting area are broken, but both can be restored in the next overhaul. At this stage, I’m pretty sure it will last a lifetime.
Can you really feel it?
Once common concern is that will you ever be able to feel the difference when it comes to such an expensive product. I assure you will. It’s a night and day difference.
The smooth and finest movement are made possible to feel by the extremely low friction damping. The absence of sliding resistance allows the suspension to follow even the slightest load change smoothly, and the damping is effective even when the suspension moves slowly. This is what correct suspension movement is all about.
Explanation of the function and features of each part
Ohlins offers four types of damper pistons with different diameters, from a minimum of 36mm to a maximum of 46mm. Why does that matter? The larger the piston diameter, the larger the shim diameter of the damper can be. Additionally, more oil can be moved for the same stroke volume. As a result, larger diameter pistons can be dialed in detail even more.
However, there are many cases where large diameter pistons cannot be used due to the frame design of the bike (especially bikes with dual suspensions setup), and the smaller diameter pistons can be used in such case. The smaller diameter pistons are more severe, but still an Ohlins.
About the reservoir tank
When the suspension is retracted, the damper rod is inserted into the body, and the oil must be released somewhere to cover the volume of the damper rod pushed out(liquid cannot be compressed). Therefore, Ohlins has a gas chamber to absorb the volume of oil from the damper rod. This gas chamber is called the reservoir tank. Even dampers that look like they do not have a reservoir tank are equipped with a gas chamber inside the damper.
However, the capacity of the gas chamber inside the damper is limited. That’s why we came up with a new type of damper with a separate reservoir tank. There are two types of reservoir tanks: one is rigidly connected to the damper body, and the other is completely independent of the damper body connected by a hydraulic hose. Theoretically, the closer the tank is to the damper body, the better. But in some cases, the tank cannot be integrated into the damper body due to frame being an obstacle.
In such cases, the reservoir tank is mounted to a different location. Many people prefer the separate type because it looks more mechanical. The difference in performance between the integrated type and the separate type can hardly be noticed.
About compression side (comp side) adjustment
This is the damper adjustment mechanism for the compression side. It is a damper adjustment to prevent the suspension from going too far. Some grades also allow you to fine-tune the damper performance separately for low speed and high speed. Generally speaking, the low speed side is for slow suspension movement on a smooth road surface, while the high speed side is for fast suspension movement on a rough road surface. The more steps there are and the finer each step is, the better.
About the rebound side (ten-side) adjustment
This is the damper adjustment mechanism for the extension side. The rebound side is the part that adjusts the damper’s original function, preventing the suspension from returning too much after contracting at the gap and rocking back. The more steps there are, and the finer each step is, the better.
About preload adjustment
Ohlins dampers can usually be adjusted without clicks. By turning the screw on the outer circumference of the body, you can shrink or loosen the spring. Basically, once the preload is set, it remains unchanged unless the body dimensions change or the riding style changes, but in most case it’s only for racing. To give you a simple example, when you are riding two up, the optical axis of the headlight points upward, right? In such a case, the preload can be applied to return the bike to its original position.
To adjust the preload, it is necessary to reach the part where the spring is positioned, but this is difficult to do because the suspension of the motorcycle is often located deep. To make such work easier, some models have hydraulically adjustable preload with the remote control dials. This is recommended for those who tend to change the preload frequently.
About height adjustment
Located at the bottom of the damper, and the overall length of the damper can be changed by turning the screw. For models with ride height adjustment, it is possible to adjust the seat height without changing the spring rate and preload settings, in case the height is beyond the target range after selecting the correct spring rate and preload. If the model does not have a ride height adjustment mechanism, you will have to compromise on the spring rate or preload to get the ride height right.
What is a single tube or monotube?
It refers to the internal structure of the damper. As the name suggests, a single tube has a single tube inside the damper, while a twin tube has a double tube inside the damper. The advantage of a single tube is that the piston diameter can be as large as the damper itself. The larger piston makes it easier to adjust the damping even with small movements.
The twin-tube damper however has another smaller diameter tube inside the main damper, and damper oil is circulated between the inner and outer tubes. Since the oil is circulated, there is less oil pressure difference inside the damper, and cavitation is less likely to occur at high speeds. Ohlins has a unique structure called “TTX”, which is a more advanced technology than conventional twin-tube system.
What is TTX?
TTX is Ohlins’ special mechanism, basically a twin-tube system. However, the twin-tube system used by other companies has oil passages in the damper pistons, and damping is adjusted by shims, whereas the Ohlins twin-tube (TTX) has no damping adjustment mechanism in the damper pistons. The piston only pushes oil away from the piston, and there is a completely independent adjustment mechanism in the oil circulation channel.
The advantage is that the pressure side and rebound side can be controlled completely independently. With dampers other than TTX, adjusting either the rebound or pressure side always affects the other side, but TTX has completely independent oil channels and completely independent adjustment mechanisms for both rebound and pressure sides, so adjustment of the rebound side does not affect the compression side, and vice versa.
In addition, cavitation (bubbles caused by rapid decompression) is less likely to occur on the low-pressure side of the damper, which is separated by a piston. The lower gas pressure also prevents oil leakage even if the oil seal is loosened, thus eliminating the need to use an oil seal with high sliding resistance. As a result, smooth operation with low friction becomes possible.
The figure below shows the conceptual diagram, but only the compression side is shown because it is complicated (in reality, there is another system for the same elongation side).
You can see that the piston has no damping adjustment mechanism.
Explanation of symbols
As I mentioned earlier, Ohlins has a part number called “Type Code”, which is a combination of numbers and letters. The meanings of the symbols and numbers are as follows：
S: Cylinder structure is single tube
T: Twin-tube (TTX) cylinder construction
36: Uses 36mm diameter pistons
39: Uses 39mm diameter pistons
44: Uses 44mm diameter pistons
46: Uses 46mm diameter pistons
Shock absorber shape and internal structure
E: Does not have a free piston in the cylinder
D: Type with a free piston inside the cylinder
P: Piggyback type with a reservoir tank
H: Equipped with a reservoir tank connected with a hose (remote type)
K: Chrome-plated type
Equipped with various adjustment mechanisms
C1: Compression damping force adjustment
C2: Compression damping force can be adjusted independently for low and high speed ranges
C4: Electronically controlled compression damping force adjustment
R1: Rebound damping force adjustment
R4: Electronically controlled rebound damping force adjustment
S: Spring pre-load, with separate hose-type hydraulic adjuster mechanism
S1: Electronically controlled spring pre-load
B: With spring pre-load and built-in hydraulic adjuster mechanism
L: With ride height adjustment function
Example of symbols
T → Twin tube
36 → 36mm diameter piston
P → Piggyback type reservoir tank
R1 → With rebound damping force adjustment
C1 → With compression damping force adjustment
L → Ride height adjustable
S → with separate hydraulic pre-load adjuster
The pinnacle of Ohlins monoshock, the structure is directly based on the one used in motoGP, and is the best suspension you can get in the world. Only the electronic controlled ones might be better than this – but that’s something you can’t buy as a replacement. For purely physical and mechanical control of the vehicle body, there is nothing better than this. The shape of the damping force adjustment needle has been redesigned, and TTX GP offers the highest level of precision and adjustability of all Ohlins dampers.
You may be wondering, “Isn’t this just as good as electronic suspension?” The only reason why production bikes use electronically controlled suspension is to cope with all kinds of situations, and they are just trying to automatically adjust the damping from flat surface track riding to large gaps like going over bumps. If you don’t have a plan of going to off roading your bike and go to the track on the same day, this suspension might be easier to set up. In fact, serious circuit racers do not use electronically controlled suspension (because they do not want the damping characteristics to change against the rider’s will). In other words, the same quality suspension used in the highest level of racing can be purchased for as cheapas $1,800.
The TTX RT is the entry model of the TTX series, based on the TTX36 Mark II and incorporating functions of the TTX GP. RT stands for Road & Track. This model is designed for a wide range of situations, including racing on tracks as well as public roads. Being an entry-level model might sounds like it’s an inferior, low-priced version, but this is not the case. The main reason for the low price is that it is not equipped with a hydraulic preload adjuster. However, those who don’t need to change the preload frequently, for example, those who only specialize in driving on certain tracks, or those who always drive with the same equipment weight, won’t have a big problem since they won’t need to change the preload frequently.
The shape of the adjustment needle inside the damping force adjustment mechanism is different from the one used in the TTX GP (the same as the TTX36 Mark II shown below), but the concept of the TTX mechanism is the same, so the advantage of completely separate rebound and pressure adjustment remains the same. The weak point is that the lineup of compatible models is limited, but if you ride a compatible model, you’re in luck!
TTX36 Mark II
This is the successor model to the innovative TTX36 rear shock absorber. The TTX rear shock has evolved the concept of the TTX mechanism, where rebound and compression are completely separated for reliable adjustment, and has been reborn as the new generation TTX rear shock under the name of Mark II. The number of adjustment levels has been increased from 20 to 25, and the rigidity of each part has been improved to maintain high road-following performance even when subjected to high loads for a long time.
Almost all models have a threaded hole in the end-eye (the part of the damper rod that attaches to the car body) for the stroke sensor to be installed, giving a glimpse of how this model is designed for full-scale racing. Although the damper is designed for racing, it can also be used on public roads. The TTX36 Mark II is designed for racing, but it can be used on public roads as well, benefiting from the latest TTX damper structure.
The mainstay of Ohlins until the introduction of the TTX, the S46 series is the one that has made Ohlins so famous. It has evolved little by little over the years, but the current lineup has an aluminum body. The so-called rear shock has reached the point of perfection, where it cannot evolve any further. It’s bolt on with model specific variations. Also, because of the familiar damper configuration of “single tube and multi-stage stacked valves,” which has been used for many years, you are able to utilize the vast amount of setting data accumulated over the past 40 years.
The multi-stage stacked-valve setting is particularly impressive, and almost everyone will not feel the need to reset it. Just by adjusting the damping adjustment dials, you should be able to handle normal street driving, mountain passes, and touring, as well as full-scale racing for the championship. It is impossible for a product to achieve this level of performance simply by having a superior construction, and unless the internal structure of the product is set up perfectly, which is basically impossible for the buyer to adjust by himself, there will be a problem somewhere. But that’s Ohlins! It’s obvious from the impressions that almost all of the purchasers have felt its greatness after just installing it.
Twin shock lineup
The original Ohlins. This is the traditional twin shock absorber, which became the reason for Ohlins’ establishment and became a legend in the racing world. In those days, monoshocks had not yet been introduced, and motorcycle suspension meant twin suspensions, so mastering two suspensions was absolutely necessary to win races. Ohlins twin shocks have reached the ultimate level. Due to the mounting position of the suspension, it is difficult to make any further progress, and it is all about how to improve the basic performance, but Ohlins has reached a level where it is difficult to go any further. Just like the S46 single rear shock absorber, it has the same “single tube and multi-stage stacked valve” configuration that is standard for high performance shocks.
This is because the multi-stage stacked valves are set differently for each car model to provide the best damping characteristics. The damping characteristics other than those that can be adjusted by dials are perfectly set for each car model, and this is the value of Ohlins that no other company can imitate. The simple design is less prone to breakage and damage, and of course, each part is fully adjustable. The design concept of the suspension system is to be fully disassembled, which is completely different from the non-disassembled stock suspension system, and it can be overhauled to restore the same performance as new.
The upper and lower mountings have direct bearing support (spherical bearing support) without rubber bushings, large capacity reservoir tank to prevent heat leakage, and a wide range setting of 30 rebound and 20 compression levels. The preload adjuster nut is also unique, with a unique single nut type adjuster instead of the usual double nut type. Even if you turn the preload adjuster just a little, or turn the dial just one click, you can feel the ultra high precision machining on your hand.
This model is based on the twin shock absorber S36 mentioned above, but has been modified to fit the shape of old cars and classic chassis. The internal structure is the same as the regular twin shock absorber, so the performance is exactly the same. The only difference is the look. In addition to the Ohlins yellow spring color, the Legend Twin is also available with black springs for those who prefer a more stock look. In the past, Ohlins twin shocks were basically steel bodies with black springs. The damping adjustment dial on the compression side is also made of black plastic, just as it was back then, making it ideal for those who want to ride the latest twin shocks with as much atmosphere as possible. Although it looks like a twin shock from that era, it is the same as the latest twin shock S36, which has been redesigned with the latest technology.
Although Ohlins is expensive, the performance has always been top-notch, and anyone who installs them can easily feel the effects. Even if you don’t know anything about suspension setting, you will surely feel the good movement. Moreover, the suspension is so docile that you can immediately feel that something has changed when you turn the adjustment dial, so there is no need to worry if you tried to set the suspension with the stock suspension but did not understand it well. If you have a bike that you plan to ride for the rest of your life, Ohlins is not an expensive investment, as it can be used for a long time after an overhaul, and will always give you a moist sensation every time you ride. Ohlins is highly recommended.
Nationality is unknown, Ryan is an experienced rider and custom bike builder, spending most of his time in garage trying to make things work. He rides, he writes, and he misses In-n-Out.