DK Custom Products

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Improved Front Suspension w/ Intiminator Fork Valves for Harley

Availability: In stock
Item #: DK-RIC-INT-39
Manufacturer: DK Custom Products

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DK Custom Improved Front Suspension w/ Intiminator Fork Valves For Harley Comfortable Ride suspension Ricor






Sportster ~ Dyna ~ Softail ~ Touring ~ Trike





Features & Specs:

  • Increased Stability in Turns 
  • Increased Cornering Ability
  • Reduced Brake Dive
  • Smoother Overall Ride
  • Faster Braking 
  • Less Wallowing in Curves 
  • More Control at Slow & Fast Speeds
  • Less Harshness over Bumps
  • Reduced Bottoming Out 
  • Improved Tire/Road Connection
  • Easy Installation 
  • Works with Standard Fork Springs & Aftermarket Springs 
  • Sold as a Pair
  • Patented Inertia-Activated Valves



Using the Intiminator in the forks, whether with stock or aftermarket springs, the ride is greatly improved.   Not only do they smooth out the bumps, large & small, it is amazing how much more stable your bike/trike will feel going thru the curves.  It is confidence inspiring.  

There is reduced brake dive, and the front tire stays much more connected to the road, improving traction, and reducing that loose, wallowing feeling.


Full Details:

Suspension Basics: When the front wheel hits a bump, the fork compresses to let the wheel go over the bump. The spring in the fork first resists this compression, then extends the fork after the bump. But without some way to control the speed at which compression and extension (also called rebound) take place, the wheel would bounce, oscillating until the energy of hitting the bump was dissipated. In order to control wheel movement, that energy has to be damped.

In a damper rod fork (which Harley uses), that’s accomplished by forcing oil through an orifice inside the fork. But this method doesn’t work well at slow compression speeds, when the oil is moving so slowly as to provide no real damping, or at very high compression speeds, when it’s moving so fast it doesn’t move through the orifice at all, a condition called hydraulic lock, which effectively stops the fork from compressing.

The Intiminator sidesteps the limitation of damper-rod forks by taking the damper rod out of the suspension equation. This is done by using a light weight fork oil, which is so thin that it passes through the damper orifices without producing any noticeable damping effect, almost no matter what the wheel speed.

The Intiminator itself is an improvement over the fixed orifices in the damper rod. It uses a flexible shim stack (in the larger-diameter base) like those in sophisticated cartridge forks, and an inertia valve (the brass-colored part under the nut on top) that opens up a bypass for faster oil flow at high compression speeds.

At low speeds over the kinds of bumps you encounter on the street, the shims alone provide damping, controlling the flow of oil and bending to allow more through if needed.

At higher speeds the motion sensing inertia valve takes over. It sits on a light spring, and remains closed until the wheel begins to move upward sharply; it then slides down and opens a port through the middle of the Intiminator that lets the fork oil flow freely, allowing the wheel to get up and over the bump as quickly as possible.

Under braking, which causes the front end of the bike to pitch as weight transfers onto the front wheel, the inertia valve remains closed, and the shim stack’s damping effect moderates dive. In this way the Intinimator reacts differently to wheel movement (hitting a bump) and chassis movement (hitting the brakes).  

The net result is front forks with amazing compliance characteristics.  MUCH Better than monotubes and mid range cartridge systems, and approaching the quality of an expensive cartridge system.

IAS Inside.  Inertia Active Suspension is a patented technology.  They dynamically adjust damping, resulting in improved riding comfort & control. 

This is acheived via a motion sensing valve in the shock body that dynamically adjusts the damping to be ideal for both dips and bumps.


Fitment:  All Harley-Davidsons Except:

The few late model HD's that have 43mm Inverted Forks (2020+ Low Rider S & Fat Bob)

2016-Up Sportster Models*

Some 2017-Up Models that have a cartridge on one or both sides*.

Note:  There are a few Models throughout the years that Harley has used a Spring and Damper Rod (Tube) on one side and a cartridge on the other.  These do not work with cartridge style suspension. 

*Many Customers have replaced the cartridge on one side with the standard damper rod and then used the Intiminators with good results.

When you order there are a few simple questions.  Your answers give us the information needed to send you the correct Intiminators, set up for you & your bike.

 When installing these Performance Valves, the fork fluid must be changed.  We recommend Maxima Racing Formula Fork Fluid. 

Fork fluid can be purchased locally, or you can use the option to add it to your order. 

Different Intiminators use different weight fluid.  If you choose to have us send you the Racing Formula Fork Fluid with your order, we will send the matching weight.  (5W for 39mm and 41mm forks & 10W for 49mm forks)


Please note:  

1.  These will improve your front suspension, both with the stock fork springs, or aftermarket springs.  In most instances, if you use aftermarket springs, they will improve your ride even more.  See Springs HERE.

2.  If you are still running stock rear shocks, you can complete your suspension upgrade by replacing them with some Performance Shocks.  See them HERE.

3.  We have package deals for complete, front & rear, suspension upgrades, which you can see HERE.

4.  To see our Complete Report on Suspension Testing and Grading of various components, Click HERE.


Go HERE to See The Intiminators Work

Customer Reviews

Great Improvement Review by Baken
I purchased these intiminator fork valves for my 2019 Road King Special. I removed the fork legs and installed with the supplied (extra price) correct fork oil for my application. I have improved handling in corners with a more planted ride. Much Less nose dive when braking. Also a much more comfortable ride with these installed. I highly recommend these to upgrade the factory front fork suspension. I do recommend having the mechanical ability and correct tools for installation. (Posted on 9/6/2023)
Excellent customer service and product. Review by Bagger
Our '08 Ultra had hideous brake dive and consistently bottomed out on harsh bumps, and would search for a line when traveling over 70mph.
After a long conversation with the folks at DKC, I ordered the RaceTech non progressive springs and Intiminator valves. I had a worry I'd make the front too stiff, but shouldn't have, the ride is perfect, no more pushing out the line on full power corners, no more line searching at freeway speeds and the brake dive is gone, completely gone. Application of hard braking now results in a nice sutble weight shift and complete confidence in the predictability of the bike.
I simply could not be happier with the changes in the bikes handling. When I also installed the 13" NexGen rear shocks the bike was transformed into a true mile eater and comfortable, predictable pleasure to ride.
Thank you very much for answering my questions, offering advice and delivering such a great product. Even the instal was easy with great, clear directions, I followed them to the letter and the results are amazing. (Posted on 7/22/2023)
Much improved Review by Wheelie 3
Customer service was great. Received in a few days. The ride was a lot better. Bumps in the road were much softer. (Posted on 7/13/2023)
Awesome customer service Review by JC
I can’t say enough about the customer service. Took my information and told me exactly what I needed. We had a hiccup with UPS losing my order but CS was all over it and made sure a new order was shipped immediately. Traveling presently and have not installed yet and but have zero doubt that the ride will be incredible. Highly recommend and couldn’t ask for better folks to do business with. (Posted on 6/29/2023)
Huge Improvement Review by Wckidd
So glad i decided to spend my money on these! Front suspension is amazing compared to stock! Soaks up the bumps so much better and they keep the front tire planted to the ground
(Posted on 5/1/2023)
Outstanding Review by Billy
Customer service top notch. Intiminators are all what has been said about them. Great product and easy install. Purchased three. One for wife’s bike (05 Deluxe), my 01 Sportster and 19 Electra Glide Standard. (Posted on 4/26/2023)
Recommended! Review by Rich
So recently put in the Intimidators Fork Valves and my '06 1200 Sporty Low front suspension feels more stable with less dive. Really glad I put them in. Thanks DK Customs! (Posted on 4/20/2023)
Great product, very satisfied Review by nevinpratt
These took the "edge" off of the suspension, and made everything feel smoother. Thank you. (Posted on 3/31/2023)
94 Road King Review by David
Easy installation. I bought and added the recommended fork oil. I really can’t tell much of a difference from stock setup. I’ve only ridden around town, but will submit a new review after putting some more miles on the bike. (Posted on 3/25/2023)
Huge upgrade for a 2018 FreeWheeler Review by Taz
This is a well thought out and executed product. If you want to take a FW up a few notches to where it should’ve come from the factory, install the comfort lift rear, progressive front springs with Intimidators. Adds safety and a much nicer riding experience. Thank you for all the great videos. (Posted on 12/12/2022)
Great product Review by Unclezip
As others have written, I shoulda done it sooner. My 49mm FXDWG was riding like a Kenworth, and driving my crazy. These things, along with a set of 412s, made a whole new motorcycle. Now it rides like a Wide Glide should on all these rough Arizona desert roads.
Thanks! (Posted on 12/7/2022)
Should’ve done it sooner Review by Wes
First became aware of these when a DK YouTube video was suggested to me. From what I heard, it made perfect sense. But I didn't pull the trigger. About 6 months later i took my whole front end apart to remove my forks (not much fun on a early model road king). I rebuilt my forks and replaced the stock springs with progressive springs. Man, I should’ve bought the intiminator valves and done it then. After a few thousand miles and a front end that still needed improvement, I ordered the valves and oil. I gotta say, this is an investment that’s worth way more than its monetary value! Easy install! Cut 1/2”’off my pvc spacers to account for the valve thickness and dropped em in. My front end is very close to my buddies who has Ohlins cartridges. And we all know what that cost. I don’t know what words to use to describe the ride other than it doesn’t knock your teeth together and throw you off the seat. Harsh bumps are still harsh bumps but they’re handled so much better. And the small stuff, it just floats over like a boat on a wave.
Highly recommended (Posted on 11/21/2022)
Excellent Review by JK78
Paired these with progressive front springs and what a difference. Highly recommend and customer service with DK is great! (Posted on 8/30/2022)
A Good Option For the Front Review by brian
I'm on the lighter sided and added these to my 2020 Road King with Progressive springs replacements too. I didn't think I needed to reach the Apex of the best possible ride available, but feel its greatly improved the front suspension, perhaps, and just about reaching my expectations for the two mods. (Posted on 8/23/2022)
Mandatory Dyna 39mm Upgrade Review by DC
I had significant brake dive and a lot of wallowing over medium freeway bumps on my '05 Dyna 39mm forks with stock springs, so after some research, I tried the heavy duty fork fluid. That helped the brake dive and wallowing a lot, but now I felt every line and crack in the roads, which bothered my hands on rides from all the jolting. So after more research I chose Intimidators because you don't have to drill out the damper rods because they are designed around very thin fork oil. Easy install, but does increase spring pre load due to the thickness of the shim stack now being added to your springs. Not a bad thing, but definitely noticeable for my 180lbs. BUT, the Intimidators produce an amazingly better ride! Lines and cracks in the road are gone. Brake dive reduced. Firm, yet supple at the same time.
Forks feel better matched to stock rear shocks. My hands don't feel beat up after rides. Totally worth it and DK Customs was great to deal with. (Posted on 8/17/2022)
Should’ve installed them sooner! Review by D.W.
These are one of those parts that make you kick yourself after installation because you realize you’ve been missing out and suffering without them for so long!

First off the install is VERY EASY. Seriously don’t sweat it, if you have the tools to get your fork tubes open you can put them in. Literally as simple as dropping them in.

I installed them in my 2014 dyna, and reused the stock springs. I’d recommend getting springs too, as I still have some more brake dive than I’d like and a little bit too soft of a ride still. And I’m a fairly light guy at 150lb. Although the brake dive now happens at a much slower rate. (Takes more time for the forks to compress.) But WOW these valves really changed how the front end soaks up bumps and becomes much more predictable going into corners and with road undulations. The dampening with these valves is so noticeable that I had to stiffen up the rebound on my Bitubo shocks two clicks each, to have the perfect ride! I think that right there shows how noticeable the change was and just how mushy the stock “damper” setup is. (Posted on 7/10/2022)
installed the Ricor intiminators from DK Customs today Review by BT
Took the forks apart and installed the Intiminators. Relatively easy job, but did take a buddy and I to put the fork cap back on considering we did it manually with out a press. Once we had the first one figured the second one only took 15 minutes or so.

Prior to the change I rode a route that included city driving, pavement cracks, bad asphalt, and a cloverleaf. I crossed a set of train tracks twice. I also braked fairly aggressively from 50 kmh to try and quantify the brake dive. After the change, I essentially rode the same path.

From my seat of the pants study, I believe the bike dives less quickly than prior when braking. It also strikes me that braking with some dive and hitting an expansion joint is less “abrupt” after the change. The bounce over the tracks is hard to say since the whole bike moves anyway. During some of the shallower bumps on the city streets, it feels like the bike is more planted. Perhaps the rebound is more controlled. It also seemed that the bike tracked better during the relatively aggressive cloverleaf turns.

All in all, I believe there is a difference; however, it doesn’t strike me as a nite and day difference like I had when I changed my ’89 and ’07 E-Glides from stock to progressive front springs and 412 rear shocks. Nor as significant as going from the ’07 to the ’19. But I believe there is a difference. As I said, it does feel more planted on the ground. Is it worth it? i am not exactly sure what i expected, but yes i think it is. the bike seems to hug the road better. i am not regretting the purchase at all

Now a word about DK Customs. these are good folks to deal with. i first started down the path for this item due to this You Tube video. i had some questions that i sent by email directly to them. Dwayne got back to me with in 24 hours both times. the tag line on their email signature is " To give real service you must add something which cannot be bought or measured with money, and that is sincerity and integrity." It looks like they live by this. really good folks to deal with (Posted on 5/26/2022)
Big improvement Review by Ken
I installed these along with the RaceTech springs on my 2019 and 2020 H-D FLH bikes. Huge improvement over stock forks. Handles bumps much better and no more brake dive. Very easy to install. I highly recommend them. (Posted on 5/11/2022)
Update to earlier review Review by Bob C
Just an update to my earlier review. Out on a ride today and was forced to really get into the brakes. The difference between the upgraded front end and the original can’t be compared. A world of difference in the ability to really get into the brakes when needed. The upgrade provides a much more controlled transition into braking. (Posted on 5/30/2019)
Front Suspension Upgrade Review by Bob C
I upgraded the suspension on a 2013 883 Iron. Based on DK Custom Products recommendation used the progressive springs and intimidator valves. The ride is now a lot tighter and more comfortable. Glad I made the switch. Don’t even notice bumps that would have jarred me before.

Installation Note: The intimidator valves would not fit into the fork tubes without sanding the expansion rings around them. They also had to be pushed into the tubes with a piece of PVC pipe (recommended by DK Customs). If you install both the springs and valves you also have to cut the provided spacers 5/8 inch shorter than recommended in the instructions. (Posted on 5/28/2019)
Excellent product Review by Owenleeme
I installed these on an 06 XL custom. I also put in progressive forks and a 2 3/4 pre load. Maybe a little too stiff but I can adjust it later. This eliminates break dive and add confidence to down hill cornering! Stock sucks, if you aren't sure DK is always been there to help out and gives the best advice. It well worth the money and probably one of the most underrated mods you can do. Its easy as pie just go on and give it a try! (Posted on 4/20/2019)
150% Better with Race Techs Installed Review by NoSlackPatriot
These were installed in my 2017 H-D XL1200X. First, I installed the Race Tech 1.03kg springs, then later installed the Ricor Intiminators. The RT springs provide a 100% better suspenion over OEM; with the Intiminators installed, the upgrade is 150% better than OEM. The ride retains its sporty performance, but adds a little more plushness to absorb bumbs in the road. Just an all-around better ride! Highly recommend!

Install notes for H-D XL1200X:

OEM Fork Oil Level is 150mm in depth, which converts to 646mL.

With the Ricor Intiminators installed, the fork oil level becomes 155mm, which is 627mL.

The Schedule 40 PVC spacer that comes with the RT Springs required cutting of 12.3mm off the length to account for the Intiminators "washers" space. The RT Spring sits in the recess of the Intiminators, hence the 12.3mm cut; which includes the loss of .74mm due to the unused washer that went between the spring and damper.

Again, very easy install and the ride is vastly better!! Very pleased!! (Posted on 11/2/2018)

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