High speed damping (used incorrectly)

What's with cars (mod, and default) that have more high speed damping than low speed? Doesn't anyone know that's not how bypass dampers (edit: velocity-sensitive damping circuits) work?

 

number A: do you mean bypass shock?

letter 2: Bypass shocks are normally used in off road applications (Ford Raptor, Baja tucks)

lastly this also sounds like your also talking about fast bump damning and bump damping witch is simulated in Beam

 

a: yes

2: bypass dampers are in every performance-oriented wheeled vehicle including mountain bikes. You might be thinking of multi-bypass dampers, which are not in Ford Raptors but are in extreme offroad vehicles. These dampers have various rates scattered across the stroke, as well as stroke velocity.

lastly: I made a post on Beam's Steam forums last year confirming my suspicions that the devs had been setting high speed bump higher than low speed, instead of lower (which is how they work--bypass--damping force reduced/bypassed at high shaft speeds) and the only change I saw was they removed the option to tune it ourselves on their cars.



I know it can be hard to understand all of the interacting factors and forces in a sim, getting the scope and scale correct, but using flatly incorrect/unrealistic/almost impossible values in critical and basic areas like the dampers makes tires harder to diagnose, terrain more difficult to design.. it's all bad.

 

ok did some more research, now it sounds more like a twin-tube witch is used in almost everything. For more rugged off-road oriented cars, struts are used. BUT I did go through the game found some things. Fast bump damping is only found on the D-series and Romer strut suspension (i used the off-road suspension so I could see the #s) both of these are rugged off-road oriented cars. The Pesima has a coilover and only has regular damping. The GM has [can't think of name rn] and also has no fast bump damping. Fast bump damping is used in off-road applications because you need 2 different damper rates. One damper rate for more extension when slowly off-roading, and one for fast driving to help improve stability. The reason for the higher Nm on the fast damping is you need a bit stiffer suspension when driving. Lower damping is used for things like mountain biking like you said, you need a smother damper for riding fast over bumps.

 

I understand the logic, but it's flawed, that's not how high speed valving works.

Strong low-speed damping values cause no undue stress on the tires, chassis, driver, etc. High speed values, on the other hand, MUST be reduced to limit explosive forces at the tires or anywhere in the sprung mass.That is why we invented multi-rate dampers, and how they have always been used in real-world applications.

The default car I had in mind was the Hirochi Sunburst with rally suspension.

 

That makes sense. I don't know if beam can simulate this sort of stuff yet or they just haven't gotten around to it. Hopefully the devs will improve on this

 

The functionality is in place. Appropriate config values are all that are missing. That's why I'm frustrated.

 

TBH, I have no idea, but it is odd indeed, probably there is logical explanation though, but you might need a developer to answer that.

It would require a valve that closes at high speed instead of opening.

 

Preface, you're correct, I meant digressive, not bypass. Both use a form of variable bypass bypass damper generally means position-sensitive, not velocity sensitive, which is progressive/linear/digressive.

On topic: you don't understand what I'm saying. Nobody builds significantly progressive shocks on purpose. The only place you will find them is in basic automotive, motorcycle, and bicycle applications.

If a progressive damper is not harsh at high velocities, it is underdamped at low velocities. Conversely if the same curve is appropriately supportive at low velocities, it will be very harsh at high velocities. There is a place for progressive springs or spring stops in offroad, but not progressive compression damping.

I have a Manitou bicycle fork from 2014 with effective low and high speed compression adjustments. Digressive dampers are common in mid to high end mountain bikes. Soon, so even will be data-logging for DH race tuning. Ohlins has been doing it with Loic Bruni.