Inside Secrets: WP A Kit Cone Valve Forks

[@c3h4organic97]

Initial idea of conical valves was the prevention of hydraulic lock during very high speed movements. Developed by A. Pfeiffer in Germany during the 90s, somehow this landed at WP. Thanks for the professional dissection of this topic.

[@MotoXXXManiac-dp1tz]

You,are on Point 👏 greetings from Germany👊💨💨

[@HPRaceDevelopment]

Most modern shim stacks dont have any lift or “lock” issues imho. At least not at the velocity ranges they use. But the cone set up could certainly go to a larger range of velocity if desired

[@m3hsid10]

The level of understanding and technical acumen you have is amazing! Thank you for the master class type of content!

[@DirtBikingwithDonnie]

Excellent video. Your videos are some of the most informative videos on KZbin.

[@mxengineer1]

As always great video with excellent explanation of key technical and design aspects. I think you need part 2 (or a series!) to explain valving for 1 vs 2.5 M/sec oil velocities....thanks again for these videos!

[@nicholaswickwire3922]

If I’m understanding how this system works properly then I think he got this backwards. If the main chamber volume is 4 times as big as the piston, then the fluid displaced by the main chamber would be moving 4x faster thorough the smaller piston. So instead of 10 m/s to 2.5 m/s it should be 10 m/s to 40 m/s through the piston. It’s simple physics A1V1 = A2V2

[@kylegarrett4071]

@@nicholaswickwire3922I believe the “main” or mid valve piston moves more oil than the base valve so it is a reduction like the example given in video… for this system

[@chrisco_moto]

I'd be really interested in this too. What I have heard anecdotally and from other comparison videos, is that at least by default, the 6500's tend to have better hold up but are not as plush as KYB (though obviously this is affected by tuning). I wonder if that is a product of the reduction factor, and sensitivity to oil speed when it comes to designing shim stacks.

[@petermoss4824]

very good video! first i have seen actually showing the cone valve setup ..... that fork tube thing looks interesting .......

[@PBmxer]

great breakdown! I think the price added to the mystique. Now I think a good technician can get similar results by revalving stock forks with a few tricks.

[@keithdowdle7405]

Great stuff. Thank you for the education. I have a ‘24 KTM 890 Rally with xplor pro suspension. I noticed that the preload on the top of the forks have detents / clicks but they are a considerable distance apart. Can I adjust the preload in between those clicks? In other words, leave the adjustment between clicks, or do I need to go all the way to each click?

[@HPRaceDevelopment]

You could but the long distance doesnt equate to large changes

[@j12racing77]

Can you please give me some info on your cone valve adaption kit for the aer forks

[@deanholonics-kz5wr]

Good video Derrick. Another good one or examples of different damming devices coul be early 2000s Yamaha Wr forks with the blowoff spring in the compression adjuster they can be set very plush for rocks and roots in a was it allow serves same purpose as cone valve as spring loaded but it’s on the passive side base valve as compared to the pushing side mid valve. A good segment to teach might be sub tanks ESPescially the tuneable ENZOs Keep pumping out the info bro

[@zardportugal]

Amazing video, pure top info. Cheers.

[@brenanshooter6936]

Can the Xplorer forks just be revalved for motocross and put on a sxf? Or are they totally different to xact pro?

[@HPRaceDevelopment]

Nothing alike, explore forks are open cartridge, single function forks

[@jowensedycastillo3531]

Awesome video thanks for all that knowledge 🙏

[@lillianwreaths4142]

So, is a cv fork an upgrade for gnar single track or are there better options? Or is the upgrade the billet lugs and stiffer upper tube?

[@HPRaceDevelopment]

Depends what you want! Imho its not much of an upgrade

[@sakariputtonen2683]

Öhlins would be one good option for this.

[@ronmor8237]

Do cone valve forks come with set preload? Or 0 preload and you can add some?

[@HPRaceDevelopment]

on what

[@ronmor8237]

@@HPRaceDevelopment so I bought WP cone valve black version for my 2020 ktm450, I replaced the springs and got the race tech ones which are 482 length and the OEM ones are 485 length. And I noticed that sharp turns the front buckles.....would you recommend I add some preload? Because right now it's negative preload...nothing at all is on the current springs

[@HPRaceDevelopment]

@@ronmor8237 Youd have try things and see what you like 10 different changes could all get you what you might want

[@ronmor8237]

@@HPRaceDevelopment on my way to the track as we speak...I'll try a bunch of things I love the testing aspect of suspension....was just curious if these forks have a preload that is stock. Thanks again

[@HPRaceDevelopment]

@@ronmor8237 they arent negative preload most forks have some

[@ericcole4926]

I have the Older Black exterior colored Cone Valve forks, Are they similar to the new forks?

[@HPRaceDevelopment]

exact same on inside

[@ericcole4926]

Thank you.@@HPRaceDevelopment

[@BlackSkyentertainment]

I own 3 sets….love them

[@JacobYoces]

I've read that the 6500 drop in kit uses the exact same components as the cone valve forks. Except for the midvalve, obviously. Can you canfirm this? Also, you said have a kit to adapt the the stock air forks to use a cone valve. Will that kit work on the 6500?

[@HPRaceDevelopment]

same basics, no cones. If you have convinced yourself that the “air is the problem” they will get you springs. Damping wise no different than stock concepts. We have a video up of wp aer forks, as well as kyb and showa. AP and webb both went back to stock component aer forks outdoors…

[@JacobYoces]

@HPRaceDevelopment actually I thought the stock xact aer forks were pretty good. I swear they have better progressive performance than the 6500s. But what do I know

[@HPRaceDevelopment]

@@JacobYoces You probably know as much or more than most media outlets

[@JacobYoces]

@@HPRaceDevelopment I doubt it. But I'll take that as a compliment.

[@craighills2382]

Good ito know ,we appreciate & trust in your understandings, to do for us

[@Zt3v3]

I've owned almost 200 KTM's, 1998-2011 and the only plush forks were 98-00 WP 50mm Extremes. To be fair, I've never had a KTM newer than 2011, I ride stuff that is 10 years old.

[@HPRaceDevelopment]

Ktm has run a variety of setting - the softest to date were called some of the “harshest”. I think people continually blame “valving” for chassis and component feel

[@thedirtdigger5990]

Pretty cool video but still too much for me to mess with, I'll just stick to the motors 😂😂

[@nuthintoprove]

Preloading the cone valve might be good for supercross. Being a off-road guy, I see no benefit with the cone valve, if you know how to set the "float" on the valve stack properly but very few do.

[@myronstambaugh761]

There is some secret sauce! I was thinking to add a small shim between the piston and the stack to flow more oil but I saw my rebound would be changed/compromised also. A floating compression stack is the answer! Ok. How do I do that?

[@jaytrolan1602]

You can do that on the compression side.. If you use a thin small diameter shim against the piston as a "bleed shim" it will help with small bump compliance. One reason for that is a face shim between the piston and a full sized face shim that covers the piston ports has a surface film tension that has to be broken for the stack to move. Buy spacing it off just a hair you reduce that tension. The result being better small bump compliance. Also, look at a face shim that has some hours on it and you'll see the in print of the piston mating surface due to that surface film tension. Further, the rebound fluid forces going past the compression stack will help bend the next largest shim (the one down from that small face shim to get a bleed) into the piston on the compression side helping close off the bleed during the rebound stroke.... I've done this type of valve stack for off road for many years and it works well....@@myronstambaugh761

[@vinceseyb2640]

Oh Derrick!!! You lost me when you said the rod displaces fluid. The correct term is that the "in coming rod requires the equal volume of fluid to be displaced through the base valve". As stated by penske and ohlins using excessive rod force will lead to higher level's of hysteresis. The moving of fluid through out the damper is done by the working area of the mid valve. WP only just learnt this hence the new fork. The cone was designed to create laminar flow. It has 2 major flaws though! My guess is the cone valve will be obsolete with in a couple of years.

[@HPRaceDevelopment]

The rod displaces fluid is an entirely accurate statement. How you wish to add un necessary words to the statement is up to you…

[@vinceseyb2640]

@@HPRaceDevelopment You have to ask yourself what exactly is placing the force on the fluid to drive flow? If it's the rod then it must compress the entire fluid volume (compression chamber and rebound) Straight from ohlins word for word. The amount of hysteresis for a certain damping force can be very different depending on the size of the piston (eg, pressure area) and the amount of oil under variation of pressure. The larger the piston is, the easier it will be to reduce the hysteresis. This is explained by the formula F=pA. F is the damping force, p is the pressure and A is the pressurized area. For a specified damping force (F) a smaller area (A) will lead to a higher pressure (p). The higher pressure will compress the oil more. This will cause more hysteresis. The piston shaft acts as a small diameter piston sending oil to the valve in the reservoir. Because the effective pressure area is very small and the total oil volume is large, there will be a lot of hysteresis from this portion of the damping force compared to the damping force produced by the main piston.

[@HPRaceDevelopment]

We make simple videos for the target audience, people who generally have never seen the insides of suspension. The shaft displaces the fluid it replaces - this is self explanatory and exactly why I said it the way I said it. If you want a deep give into theory - that's not what our channel presents. You act as if fluid compressoin is a large concern in these systems - when in reality it is of almost zero concern. The relationship between base piston size - and damping rod is a critical one - and I explained it as plainly as I could in one non scripted video take. People miss so much of the basics who think they are "theorists". The reality is the total velocity range (what damping cares about) is limited the larger we make the base valve diameter. This can be highly desirable if we wish to limit our peak damping amount. We also get mechanical advantage. This is good and bad - if you want to produce MORE damping force from either piston - slower velocity flow through said piston makes that hard to do. On the flip side - if we want to produce LESS total damping - the larger diameter base valve makes this easier to accomplish. Pressure is pressure, period. In order to prevent cavitation on the mid valve we require a minimum PRESSURE from the base valve, not a minimum FORCE.

[@vinceseyb2640]

@@HPRaceDevelopment you mentioned in a previous video the variation between Tomacs bike and the KTM's, particularly in the rebound phase. That's down to good pressure management on kyb's part. Despite popular belief pressure balancing is more than just avoiding cavitation. That's where the rod displaces the fluid theory fails. KTM/WP have been doing extensive research in the back, the outcomes from that research have brought about changes. This video displays hysteresis kzbin.info/www/bejne/hHLQiWawft2IaMksi=wh2wtsWo4mcgz-wM

[@HPRaceDevelopment]

@@vinceseyb2640 The rod displaces fluid, PERIOD. How you control this displaced fluid is entirely seperate topic. Pressure balance is what I just spoke on - not FORCE, as you said. The difference between the fast rebounding bikes - tomac, lawrences, and what WP ran indoors - is NOT pressure balance management. It's settings selection. WP ran a much faster rebound outdoors...The hysterisis you show is desirably in that instance - he needs the wheel rebounding much quicker IMHO. But hysterisis has FAR more to do with inertia, deflection amount, and friction than pressure balance.

[@BAYAREAMX]

Most cone valve forks at the pro level of racing just have regular shims in them.

[@Runk3lsmcdougal]

Source?

[@BAYAREAMX]

@@Runk3lsmcdougal google it, lots of info about it. More specifically Michael Lindsay from vitalmx (he used to work at Enzo) had a lot to say about it. Also, I have cone valve forks, and my suspension guy (very reputable) said the same and replaced the cones with race tech gold valves. Cone valves can work well but can be difficult to get just right. Whereas regular pistons and shims have long been figured out.

[@joelballard4955]

Awesome stuff. Very informative. Soooooooooo much money for those cone valves. How much money is that per second gained on a track for a old fat vet? Lol.

[@HPRaceDevelopment]

Lots of money - some guys swear its huge some say its not

[@kylegarrett4071]

I want more!! Whatever you got. Ha #bakingsodacooking

[@petermoygannon698]

And KTM Can't mass produce this better fork The alloy is allot more expensive I here cost of gold . I don't need no billet lower axel holder either . So they that expensive part they can keep . Gold cone valve can't mass produce that . Again made of moon rock material .

[@HPRaceDevelopment]

Many riders prefer shim set ups…certainly kyb and showa as companies think so all the way to their best team products… As with anything wp could sell it stock but they wouldnt have something else to market to you as an upgrade

[@edsonbarcellos4541]

To be honest the Black Jack from MX TECH is much better than WP CONE VALVE!!!! NO COMPARISON WHATSOEVER !!!!

[@HPRaceDevelopment]

I THINK THE BOYS AT MX TECH ARE GREAT AND THEY SELL A NICE PRODUCT BUT AT 12k WHATEVER IT COSTS ITS A HARD SELL

[@fampol2509]

You better stick to engines

[@HPRaceDevelopment]

Lol.