Ohlins Suspension - Valving #3 Clamping Shims

[@redhorse554det1]

hi doug, glad one can hit the replay button and further comprehend the science about shock pistons and their workings..thanks for sharing.bob

[@theohlinsguy4649]

Thanks for watching!!

[@cafeandfighters]

Hi, big fan. Just found you and have been binging on your vidios. I appreciate your knowledge and your willingness to share it. I am an old-timer MC mechanic/rider who has rebuild and upgrade many forks and shocks. Your vidios have covered many gaps in my education and explained things I was just wrong about. Thanks.

[@theohlinsguy4649]

Thanks! I'm just trying to pass on what I know so interested people like you can wade through all the mis-information out there. I was just lucky to learn from the best.

[@lenaeleomar]

Thanks for making these videos, very informative and good watches. Keep it up

[@theohlinsguy4649]

Thanks!!

[@Mineratron]

Great videos, thanks for sharing. Nice and simply explained. I run Ohlins on the rear of my track bike, quality stuff. Front is showa with k-tech internals but works ok.

[@theohlinsguy4649]

Thanks for watching!! Knowledge is power (lap times)

[@Mineratron]

@@theohlinsguy4649 deffo! I’m an engineer (power plants) but love to tinker on my bikes and enjoyed learning about suspension, it’s fascinating. A good mix of engineering and feel, a tactile thing in the middle. Learning to set up track bikes and dirt bikes has been great. Dirt bike fork valving the next challenge (WP cone valves). 🤓🪛🔧

[@theohlinsguy4649]

@@Mineratron Cone valves are one of the many things I know nothing about!!

[@theohlinsguy4649]

@@Mineratron Cone valves are one of the many things I know nothing about!!

[@Mineratron]

@@theohlinsguy4649 it’s a closed cartridge fork where the mid valve is is like a spring loaded needle valve… but it’s not Ohlins. 🤓😉😃👍

[@dominikd.9249]

Konkretnie i na temat , zawsze miło popatrzeć na dobrego fachowca

[@theohlinsguy4649]

Dziękuję za miłe słowa!

[@Pereke69]

Still watching your videos i learn a lot, thanks and hope you upload new video with more shim magic and dynos

[@theohlinsguy4649]

Thanks! Working on it.

[@lukasztetich6302]

Hi, I have a technical question for you regarding the valve shims. If the shock is quite an old shim stack would lose some of its characteristics over the time. Do you replace all of them during the service even if you don't customize the valving? Can you reuse them? You make great videos! Thanks

[@theohlinsguy4649]

Good question. I don't replace shims unless I see some sign of wear which is very rare.

[@lukasztetich6302]

@@theohlinsguy4649 Thank you. I'm a technician quite new to the suspension setup I've only been doing it for about 6 years. I mostly just service shocks on my own bikes and friends. Technical information is very limited on this subject and it's hard to find the right answer if you don't have someone with real experience. I have tons of questions I just don't want to flood you with them. I really enjoy all your videos lots of great information. Could you recommend any technical literature that would be valuable? Recently I've upgraded the spring from 140 to 167N/mm so would like to try valve my shock just to compensate for the stronger spring. Just not sure where to start.

[@theohlinsguy4649]

@@lukasztetich6302 Thanks! Always happy to try to answer questions. As far as re-valving for spring rate, I am not a fan. No one has given me a satisfactory answer on why to do this and what kind of valving change would be necessary. As far as I can tell a higher rate spring stores the same amount of energy as a lower rate one for any given event. The higher rate one just moves less and so would your suspension. Also, if the spring is too stiff I would think that some of that energy would be transferred to move the sprung mass so the spring would actually store less energy. If there is a difference in suspension velocity and the damping is good the shock would automatically put out damping relative to that velocity. Maybe there is some dynamic I am not aware of. I am also not a fan of stiffer springs. Soft is better. The trick is to get your spring and damping working together and each doing there part. Let me know your thoughts or what you have been told about why damping needs to be changed for spring rate and what that change might be. I am always willing to learn.

[@lukasztetich6302]

took me a bit to get back to you. Thank you for all the explanation! I mostly work on one bike r1200gs Right now I have 3 different sets of shock stock ESA made by Showa, Ohlins with internal dividing piston and Elka with remote reservoir. Right now I'm testing Ohlins with a stiffer spring than the stock (sag is correct stock spring is too soft I need maximum preload to set the sag right on the stock suspension ) Ohlins comes with 100%more compression damping Then stock shock 80N of force at 10Inch/s Ohlins 150N Elka 220N And what goes with it more compression less rebound for aftermarket shocks. All the shock feel okay Ohlins and Elka is very firm and I think they too stiff on the high-speed compression I can feel every sharp bump at high speed all gets transferred to the rider seat. So the question would be how much compression damping is needed and why we see so much difference for the same motion ratio. They all linear damping Showa comes with PDS. Do you have a general rule of thumb how much damping is needed for the given motion ratio?

[@MrMarc3000]

Thanks for these very interesting and informative videos! They really give great insight in how mono tube shocks work and how they can be tuned. I was quite intrigued by the statement of an Öhlins competitor, so I googled it and found it very easily. They claim “Large 40mm piston for more precise and consistent damping control (23.5% more damping oil flow than Öhlins TTX 36mm piston)”. To be honest I don’t see what’s wrong with that statement. A 40 mm piston displaces 23.5% more oil than a 36 mm piston for a given stroke. A bigger piston gives more precision on the damping due to the smaller influence of mechanical tolerances. And the higher oil flow (and probably bigger capacity of the damper) means less increase in temperature of the oil, so more consistent damping. I don’t mean to be negative, but I really can’t see what is wrong with their claim. So can you please explain? Thanks in advance!

[@theohlinsguy4649]

Ohlins makes a 46mm single tube shock if that is what you want. Nitron is a single tube shock and operates in a completely different way than TTXs. Comparing the two is ridiculous. Why aren't they comparing their shock to an Ohlins 46mm? Why doesn't MotoGP use Nitron shocks then? Ohlins is also used in top automotive teams. This kind of thing is marketing hype IMO. You can use Nitron if you want but I would be careful buying into the hype.

[@theohlinsguy4649]

Also words like "precision damping" and "influence of mechanical tolerances" are BS. What does that really mean??

[@MrMarc3000]

@@theohlinsguy4649 my comment was not a dig at you or at Ohlins. In fact I have an Ohlins R&T kit for my car on order (which is taking forever, Ohlins logistics seem to be an absolute joke), so I do believe their product is very good. The comparison Nitron makes is completely generic in a sense that it is applicable to any 40 mm piston vs any 36 mm piston shock. The fact that they compare it to Ohlins I see more as a complement, as apparently they look up to Ohlins. But as you said, all marketing

[@theohlinsguy4649]

@@MrMarc3000 I think they compared it to a TTX36. That is not a generic shock. It works completely differently from a single tube shock. Yes, it is sometimes very frustrating waiting for parts from Ohlins. One of the problems is that they make soooo many different products that it is hard for them to anticipate how many of each to make. They schedule manufacturing months ahead of time so if they run out we have to wait until the next cycle.

[@DaStuntChannel]

Hi Douglas, wouldn't oil weight also be a "brush"?

[@theohlinsguy4649]

Hi. I don't understand the question. Tell me more

[@DaStuntChannel]

@@theohlinsguy4649 You mentioned that Pistons, shims and bleeds are your "brushes" for the art of restricting flow, wouldn't Oil weight be one of them?

[@theohlinsguy4649]

I get it now! Changing oil viscosity to effect damping is a bad shortcut. That is not what oil is for. You might change the damping a bit but it could cause other problems. Stick with the other "brushes" you have mentioned.

[@DaStuntChannel]

@@theohlinsguy4649 Right... I live in argentina and need 8mm ID, 12-20mm OD shims and I can't get it anywhere in the country which is limiting the tuning

[@eflanagan1921]

Looks great to me !May try to contact re Motorcycle shock service , but I am east coast!

[@theohlinsguy4649]

Hi. No problem. Contact me on my email [e-mail]

[@xmp-vp8wt]

If you reduced the diameter of the clamping shim, on the rebound side, would it soften the damping, at all speeds (say, between 1-10in/sec), by the same percentage?

[@theohlinsguy4649]

If i understand the question it should change the rebound damping at all shaft speeds and not really effect the compression damping. This is what I find with linear damping. I don't know if you are doing digressive or some other damping scheme as I never do them.

[@xmp-vp8wt]

@@theohlinsguy4649 Yes, that's what I was getting at 🙂. If you wanted to soften a rebound stack by, say, 10% - would you change the shims, or try a smaller clamping shim?

[@theohlinsguy4649]

@@xmp-vp8wt Depends on what clamping shim is in the stack. If it is already the smallest diameter you would have to change the stack. If you have a larger clamp you could put on a smaller one.

[@phatford37]

Great vids very interesting, I’m having oversteer problems mid corner, the softer spring rates I have the better it is, low speed is on min, from your vids seams like it’s over damped does this sound right?

[@theohlinsguy4649]

I think that you probably have too little compression damping and too much rebound. If you have rebound adjustments, run it the way you have it, come in and dial out all the rebound you can and go back out. You should see a pretty noticeable difference.

[@phatford37]

@@theohlinsguy4649 I have avo 3 ways and yes I run the rebound to softest setting and it got better, I was running 180lbs springs, when I took them in he said try softer springs now 150lbs he also said he could take some shims out, also said about progressive springs, but after watching your vids I don’t want to do that way. Am looking at ohlins that’s how I found you

[@ryanliversage]

So intrigued

[@theohlinsguy4649]

Thanks Ryan. It is all very interesting to me too!

[@wooodsryder]

Are the TTX inserts as easy to revalve as a convention fork...say KTM Aer or Xplor?

[@theohlinsguy4649]

I am not familiar with the forks you referenced as I only work on Ohlins. That being said, I think that revalving the Ohlins forks would be quite straight forward if you have the correct tools.

[@alexandergavrilov5491]

Hello, How to calculate the damping speed?

[@theohlinsguy4649]

Hi Alexander. As far as I know the only way is on a dyno or have some linear data collection on your vehicles shocks

[@alexandergavrilov5491]

@@theohlinsguy4649 If I want to reset the shim stack, then how can I correctly calculate it for weight and height if I do not know its speed?

[@theohlinsguy4649]

I don't think damping has anything to do with height and weight. I think that is the job of the spring@@alexandergavrilov5491

[@rideordivekerry4830]

Thank u for sharing years or knowledge

[@theohlinsguy4649]

Thanks. Hope it was helpful

[@rideordivekerry4830]

@@theohlinsguy4649 I have one question, when removing those so called crossover shims I assume it’s going to stiffen up so how many face shims should I remove to kind of compensate. Any suggestions would be appreciated.

[@paulcreevey9168]

Fantastic Videos. Thank you.

[@theohlinsguy4649]

Thanks!

[@vinceseyb2640]

Kyb invented twin tube and came to the conclusion that it wasn't suitable for performance applications. The more oil you flow the more control you have over the whole damping curve. A shock that flows less oil will require a firmer stack.

[@theohlinsguy4649]

More snake oil. I also doubt that KYB invented the "twin tube". I have some Armstrong shocks here that are twin tube and are 60 years old. I don't think you understand the meaning of "twin tube" as it applies to Ohlins TTX technology. If you think that KYBs are superior then by all means use them. Thanks for the comment and your interest in dampers and damper technology.

[@vinceseyb2640]

@@theohlinsguy4649 hey your video are great and agree with alot of what your saying. Dont quote me but I believe kyb developed the twin tube concept in 1956. Im personally unsure of the idea of twin tube as in the motocross world it generally means the damper body is smaller and displaces less oil. I know first hand a 50mm shock with 145 stroke is easier to find a balance between hold up, compliance and big hit resilience over a shock that has 125mm stroke for the same wheel travel. I find it very interesting that in the dirt bike world ohlins, wp, showa and kyb all work off different philosophies with emphasis on different valving and which piston, either the base valve or mid valve they rely heavily on.

[@theohlinsguy4649]

@@vinceseyb2640 Thanks for the input. I don't believe that "hold up" is the job of the shock.

[@vinceseyb2640]

@@theohlinsguy4649 the spring supports the mass, but valving has a significant impact on ride height in motion.

[@theohlinsguy4649]

@@vinceseyb2640 What is it that you race and with whom do you race? Explain how you think valving effects ride height "in motion"