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Old 26th September 2010
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Default Ricor brings world class suspension to sportsters

Ricor brings world class suspension to the Sportster.

This thread is about getting the best possible suspension under a Sportster. Ride all day in absolute comfort. The bike must handle well at all times, no matter how bad the road is. With Ricor Intiminators in the forks and IAS (Inertia Active System) shocks, the Sportster is no longer limited by the suspension.

Here is a link to their main web page, with their own explanations.
Ricor Racing Shocks.

Getting the Ricor IAS shocks to work well on my Roadster has been a major pain. Brian (President of Ricor) would send me a pair to test and I would call him back and say they sucked. But then I have told most of the major suspension companies their stuff sucked. The difference was Brian would make changes and send me another pair. I have forgotten how many different versions we have tried. Unfortunately, Ricor got so busy building other suspension stuff, sending me another version of the shocks frequently got placed on the back burner. Sometimes I got so busy with my own life that I also put test riding on the back burner. It got so involved Ricor actually bought a rubber mount Custom to get more test riding in. So, my apologies for the delay.

The end result is nothing short of amazing. The final shock tune ended being far different than Brian originally expected and far different from set ups used for other bikes. But that is what it took to get it right for rubber mount Sportsters.

So how do they feel? I was afraid you’d ask, because I have been trying to figure out a way to explain that for a long time, and not sure I have it figured out yet. First, it is important to understand how they work. There are two different hydraulic circuits that control damping. The wheel circuit has the inertia valve which opens ports in response to wheel movement that reduces damping to minimum levels in one direction of wheel movement. The chassis circuit has a shim stack that stabilizes the chassis when the wheel moves. The Intiminator in the forks uses the inertia valve to blow off high speed compression damping. The inertia valve in the shocks is opposite, it blows off rebound damping when the wheel is unloaded. The end result is the wheel is free to move much faster over road bumps and dips, yet the chassis feels more stable than conventional damping systems. At least for now, I am going to skip any longer technical explanations which get tedious and detailed.

You can feel this while riding. Adding the IAS shocks feels different than adding the Intiminators. I think a big part of it is related to the rear wheel being much heavier than the front and the fact that the rear wheel tends to transmit bumps straight up the riders back.

After adding Intiminators, the forks worked so much better, guys had to retrain their brain and change riding techniques a bit. Specifically, they could aim for the bumps rather than avoiding them. Adding the IAS shocks is the same, but different. The first impression I get is the rear wheel moves much faster, almost alarmingly fast over bumps and dips. That translates to the tire tracking bumps and dips of the road better and maintaining traction better. The second impression is how smooth the chassis is. That translates to more rider comfort.

Once you get used to the differences from regular shocks, the Intiminators and IAS shocks provide a very good road feel. If there are 3 bumps in the road, you will feel 3 bumps. If there is a big dip, you will feel the dip. If there is a series of rollers, you will feel the rollers. Ricor suspension never feels harsh, never feels mushy, and never feels like the tire is loosing traction with the road.

How do the Ricor Intiminators and IAS shocks compare to other products on the market? For some, cost is a major factor in that comparison. Like all performance mods, top of the line performance does not come cheap. To my knowledge, Ricor is the only company that offers truly high end performance for both forks and shocks in the $1000 price range. Ricor also offers a money back guarantee. Don’t even try to mention Progressive, Works, Race Tech or the popular Road King air shock in this comparison. There are a few other high end shock companies, but very few people have tried them.

That leaves Ohlins. I haven’t tried Ohlins on my Roadster, so I cannot provide a direct comparison. However, my other bike is a 2005 Ducati Multistrada with Ohlins which have been set up with springs and valving to match my weight and riding style. Ignoring the obvious differences in the bikes, like the Multistrada having an extra 2 1/2” of travel, over normal road conditions, I like the ride of my Ricor suspended Roadster better. The big difference is the Ducati tends to feel like the chassis moves up and down in the vertical direction much more than the Roadster. Is it bad, no, certainly not bad enough to bother sending back the Ohlins stuff to redo the internal adjustments. I think it simply reflects the difference in conventional shim stack damping systems vs the inertia valve damping system.

Yes, it’s true, my Ricor equipped rubber mount Roadster has better suspension than my Ohlins equipped Multistrada. That about sums it up.

Keep in mind I have been testing the 13.5” shocks with the “Sport Tune” on my Roadster with Intiminators in the forks. I have tried 3 different spring rates with my Ricor shocks. Changing springs does not seem to have nearly as dramatic effect on ride quality as I noticed on conventional shocks. In general, shorter shocks will need stiffer springs. With Ricor shocks, stiffer springs will ride a bit stiffer, but the biggest difference is how the different springs change how much travel is used. Riders who want the shorter shocks, still should be able to get a very good ride. Over 90% of normal road hash, I use only about 1½” of shock travel. Which is the travel available in the 11” shocks. (Ricor’s website currently states 1” travel for the 11” shocks, but they made changes to the Sportster shocks to get an extra ½” travel.)

Ricor has chosen to go with straight rate springs, but with enough different spring rates available to correctly match rider weight and shock length. The springs can be changed at home without special tools. The only hard part is getting the metal bushing in and out of the rubber grommet so the lower spring perch will slide off the shock. Using a vice to push the metal bushing in and out is easy. I have also pried the metal bushing out with a screw driver and pliers, but that tends to damage the rubber grommet. Preload can also be adjusted by hand, no tools needed.

These shocks tend to need a rather long time to break in time and loosen up, 300 to 500 miles. So, save your ride reports until after 500 miles.

Be careful to not over tighten the shock mounting bolts. If you smash down on the rubber grommets too much, you can actually bind up the wheel travel. I use thread locker on all bolts. Snug the bolts down to seat everything, then back off 1/4 turn. The bottom bolt should be just tight enough to keep the bolt straight in the swing arm mounting hole without smashing down on the rubber gromment. (EDIT: My original description of...after snugging down the top bolt and backing off until the washers are free to spin... is probably too loose. I changed it to backing off the bolts 1/4 turn.)

I am not sure if the stock Torx bolts are long enough for the Ricor shocks. Those Torx bolts went in the trash several years ago.

I will try to get some pictures next week.

For those who don’t know the history, I bought my Roadster in 2006. Before that, it was “common knowledge” that Sportsters, especially rubbermounts, rode stiff and handled lousy. I worked with Whittlebeast, and others, to develop suspension packages that worked. This is the link for those who want to learn basic suspension set up information. If you ride a height challenged Sportster, be sure to read about the Whittlebeast Low and Sportytrace Nightster suspension mods.

The first seven pages of suspension by XLXR

Then Ricor came along and offered me a set of Intiminators, and Vibranators, for free, in exchange for my reporting on this forum how well they worked. As far as I know, the Intiminators are still the best damper rod fork mod available today. Below is the link for the original Intiminator thread. In it are multiple links to the ride reports of other guys who purchased Intiminators. Be sure to start reading AFTER the animation of the Intiminators, everything before that was just speculation. The animation is on page 6, post 53, another animation is on page 11, post 104, and my first ride report is on page 14, post 136.

Front forks...what can we do? I have the answer

I am posting those links because there is just too much information to repeat here. Ricor shocks are not magic. You still need to set up the forks correctly to get the bike to handle correctly. If you are going to buy these shocks, put the Intiminators in the forks as well. Actually, you don’t have to put the Intiminators in the forks, but if you don’t, I can now say “I told you so.”

Suspension threads tend to get very long, especially if a guy has some problem we have to talk about. In an effort to keep the length of this thread reasonable, I am going to ask guys who install the Ricor shocks to start their own thread and post a link and brief description in this thread.
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Last edited by XLXR; 27th September 2010 at 08:15..
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Old 26th September 2010
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[IMG][/IMG]

To change springs on Ricor shocks, first pull the metal bushing out of the rubber grommet. A vice and sockets make it easy. Prying the metal bushing out with a screw driver and pliers can be done, but may damage the rubber grommet. Unscrew the top spring perch until you can raise the lower perch above the retaining ring. Carefully remove the retainer ring. The lower spring perch and spring will slide off. Be careful with the retainer ring, do not use tools or force to get it in or out. Do not bend or stretch it.
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Old 26th September 2010
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thanks for the info! I'm going to budget in a pair next year after I upgrade my cars exhaust.
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Old 26th September 2010
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Quote:
Originally Posted by XLXR View Post
First, it is important to understand how they work. There are two different hydraulic circuits that control damping. The wheel circuit has the inertia valve which opens ports in response to wheel movement that reduces damping to minimum levels in one direction of wheel movement. The chassis circuit has a shim stack that stabilizes the chassis when the wheel moves.
So... the "wheel" and "chassis" circuits are basically separating high- and low-speed damping?
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Old 26th September 2010
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Thanks John!
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Old 26th September 2010
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Quote:
Originally Posted by XLXR View Post
First, it is important to understand how they work. There are two different hydraulic circuits that control damping. The wheel circuit has the inertia valve which opens ports in response to wheel movement that reduces damping to minimum levels in one direction of wheel movement. The chassis circuit has a shim stack that stabilizes the chassis when the wheel moves. The Intiminator in the forks uses the inertia valve to blow off high speed compression damping. The inertia valve in the shocks is opposite, it blows off rebound damping when the wheel is unloaded. The end result is the wheel is free to move much faster over road bumps and dips, yet the chassis feels more stable than conventional damping systems. At least for now, I am going to skip any longer technical explanations which get tedious and detailed.
Is that correct?

I agree that little or no high speed compression damping is desirable (front or rear), in order to allow the suspension to compress quickly in repsonse to sharp bumps, and that more low speed damping is desirable to reduce wallowing in bends.

However, I can't see how the shock, once it is compressed, can determine whether it should rebound quickly or slowly to prepare for the next bump. Indeed, the rate at which a shock rebounds (without damping) is, I imagine, determined by the spring rate. The spring rate does not change (unless, of courese, it's progressive wound - which these are not), so you can only tune the rebound damping to suit that one spring rate. (??!!)

Last edited by steelworker; 26th September 2010 at 14:44..
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Old 26th September 2010
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Quote:
So... the "wheel" and "chassis" circuits are basically separating high- and low-speed damping?
That subject has been hotly debated on other forums. From an over simplified perspective, it is basically correct for the Intiminators in the forks. However, it is more accurate to think in terms of wheel movement being controlled by a different hydraulic circuit than the hydraulic circuit that controls chassis movement.

Conventional forks, whether damper tube or cartridge/shim stack, provide the same damping characteristics whether the wheel is moving up in response to a bump in the road, or when the chassis is moving down in response to fork dive while braking.

The inertia valve/wheel circuit in the Intiminators opens the hydraulic ports only when the wheel is moving upward while it tries to follow bumps in the road. That allows the wheel to move upward as fast as other factors such as spring rates, stiction, and oil height will allow.

If your riding on a perfectly smooth road and hit the front brakes, the inertia valve will remain closed. The fork oil will then be pushed through the shim stack/chassis circuit. Since the inertia valve/wheel circuit lets the wheel move upward in response to bumps, the shim stack/chassis circuit can be set with much stiffer damping characteristics. The end result is the wheel can move faster so it tracks the road better, but the chassis moves slower so the rider feels less bumps.

One of the key things that helped me understand this is looking at the relative fork shaft speeds seen while riding. Shaft speed refers to how fast the fork tubes are moving in relation to each other. High shaft speed is in the area of 100"/second. I have read reports where 300"/second are possible. This is when the tire hits a 1" high bump at 70 mph.

Slow shaft speed occurs at about 1"/second. This occurs as you hit the front brake before a corner and the forks slowly compress. If you graph shaft speed, you would see a smooth curve of slow shaft speeds with spikes of very high shaft speeds that do little to effect the overall graph.

The different hydraulic circuits in Ricor Intiminators are tuned to match this primary characteristic of different shaft speeds AND provide a different damping curve depending on whether the wheel is moving up or the chassis is moving down. Conventional damping systems cannot make that distinction.

What happens in the shocks is a bit more complicated. Due to fundamental characteristics unique to motorcycles such as short wheel base and high center of gravity, the inertia valve/wheel circuit in the shocks controls rebound damping, opposite the Intiminators.

If you go over a big DIP in the road, the momentum of the chassis may hold both the chassis and wheel up in the air for a microsecond. If the wheel is up in the air, unloaded, not in contact with the road, the only thing (besides gravity) pushing it back down is the rebound force of the spring. In this case, the shock inertia valve/wheel circuit opens to blow off virtually all hydraulic rebound damping so the wheel can move back down as fast as possible to regain contact with the road as quickly as possible.

Now assume you go over a bump (or bump after a dip) where the tire remains in contact with the ground so the shock spring must compress. Any time the spring compresses, it must rebound. When the tire is on the ground, the rebound force of the spring must move the chassis upward. In this case, since the tire is already in contact with the ground and therefor cannot move downward, the inertia valve/wheel circuit remains closed, and the hydraulic fluid is pushed through the shim stack/chassis circuit as the chassis moves back up.

I never really understood the concept of momentum holding the chassis up until I started to think about my days racing dirt bikes. In dirt bikes, unloading the suspension and getting air borne before hitting a bump or dip is an important survival technique.

I hope that explanation helps readers understand the difference between high/low speed damping and chassis/wheel movement.
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I think that talking about different circuits acting, depending on whether the wheel or the chassis is moving is at worst misleading, and at best confuses the matter.

The dampers are not capable of "detecting" whether the wheel is moving or whether the chassis is moving. They are not linked to any high-tech monitoring system. All they can do is respond, according to how they are tuned, to the speed of suspension movement. How, for instance, can rebound damping react differently according to whether the wheel has dropped into a dip, or is rebounding from being compressed by a bump?

Let's be clear that when we're talking about high speed and low speed damping this refers to the speed of suspension movement, and has nothing to do with vehicle speed. Yes, I see how it is possible (for compression and for rebound) to set up separate circuits, each of which will respond differently according to the speed of suspension movement; but I cannot see how they could respond differently according to where the suspension is within its range of movement, which is what is effectively being claimed.
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Quote:
Quote:
Originally Posted by XLXR View Post
The Intiminator in the forks uses the inertia valve to blow off high speed compression damping. The inertia valve in the shocks is opposite, it blows off rebound damping when the wheel is unloaded.
Is that correct?
Yes, it is correct. Keep in mind, it has taken me nearly a year to figure out how to explain, so I understand it being a bit difficult to reprogram old thinking patterns.

Quote:
I agree that little or no high speed compression damping is desirable (front or rear), in order to allow the suspension to compress quickly in repsonse to sharp bumps, and that more low speed damping is desirable to reduce wallowing in bends.
True again, but it gets a bit more complicated when you factor in whether the tire is in loaded or not (in contact with the road or not) and which direction both the tire and chassis is moving. They can move in the same or opposite directions, at the same time, and switch at any time, depending on road conditions.

Quote:
However, I can't see how the shock, once it is compressed, can determine whether it should rebound quickly or slowly to prepare for the next bump.
Obviously, the shock cannot see the next bump. However, the inertia valve/wheel circuit can, and does, detect tire vertical tire movement. If the tire is in the air, you want it to get back on the ground as quickly as possible. If the tire is in contact with the ground, you want to minimize the force transmitted up to the rider as the chassis moves upward. Restoring shock compression to a neutral point such as at rider sag as quickly as possible is the best it can do to prepare the shock for the next bump.

Quote:
Indeed, the rate at which a shock rebounds (without damping) is, I imagine, determined by the spring rate.
AND if the wheel is in the air, or already in contact with the ground. Since the force of the spring is constant (at a set distance of compression) the lighter wheel will rebound faster than the heavier chassis.

Quote:
so you can only tune the rebound damping to suit that one spring rate. (??!!)
Yes and no. Heavier springs do have more rebound force. I have tried 3 different spring rates with the prototype Ricor IAS shocks. Heavier springs do feel a bit stiffer on compression, but also tend the make the shock rebound faster. If the shock can rebound fully before it hits the next bump, a stiffer spring may actually feel softer. The Ricor IAS shocks are the only shocks I have felt this on. The biggest change I noticed between the different springs is how much travel was used. I was surprised how well the same damping curves worked with different springs. Much better than with conventional shocks.

I have no idea how Ricor will change the shock tune to match spring rates. That is up to them.
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Originally Posted by XLXR View Post
Since the force of the spring is constant (at a set distance of compression) the lighter wheel will rebound faster than the heavier chassis.
OK, I can see how this is correct, and where the hi- and lo-speed rebound damping comes in, which is something which I believe is not available on even the highest spec road shocks, and I doubt that most race shocks have this split either. So I guess the shocks come with zero hi-speed compression damping but a certain amount of lo-speed compression damping dialled in?
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