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Suspension setting when taking in mind the second hit

saruti

saruti

Turbo Monkey
Oct 29, 2006
1,173
75
Israel
Tire casing is for grip. Not damping. The air in the tire act like a fogo stick.
I wonder if you can use a inner tube, that can only air to certain size. 1 to 2cm smaller than the tire. Like what Sam Hill rode for a while. But, with some material that will close the gap between the inner tube ( 100psi) and the tire.
Thats way you still have easy insertion. And good daping
 
Lelandjt

Lelandjt

adorbs
Apr 4, 2008
2,636
997
Breckenridge, CO/Lahaina,HI
SylentK said:
Which reminds me. Are you still on 808 time?

Man, snow here is less than you'd expect. Like Arrowhead and Bachelors Gulch are not open yet. You can use their lifts, but not open to ride. Not sure what's open at Breck. Went to the Beav, even tho we stayed near Vail. Peeps at Vail were reporting super thin conditions. Less than impressive, I'd say. Snow guns still rockin'
Click to expand...
No Hawaii for me until I can buy a property on Maui's North Shore. Lahaina's gone, sold my land for pennies. I'm in Queenstown, NZ right now loving life. The wife & I have our enduro bikes with us and riding a different spot every day! My parents suddenly fell on bad health so when this trip is over we're moving in with them in Mystic, CT for the foreseeable future. Hoping to get back into the cycling scene there that got me started in high school.
 
troy

troy

Turbo Monkey
Dec 3, 2008
1,026
785
saruti said:
Tire casing is for grip. Not damping. The air in the tire act like a fogo stick.
I wonder if you can use a inner tube, that can only air to certain size. 1 to 2cm smaller than the tire. Like what Sam Hill rode for a while. But, with some material that will close the gap between the inner tube ( 100psi) and the tire.
Thats way you still have easy insertion. And good daping
Click to expand...
1704739434139.png

+ tannus insert
1704739533332.png


1704739477236.png
 
saruti

saruti

Turbo Monkey
Oct 29, 2006
1,173
75
Israel
Sorry. I got confused between pattern and casing.
Anyway, both not for damping.

Thanks Troy for the tannus insert picture.
But, this tube will inflat forever. And push the insert and make it harder. And still there is air that will bounce back any hit.
If the tube will stop at a size, like the procore. And hold the insert at place, with 100psi, and lets say you can buy inserts with feel of:
20psi
22psi
And so on...
It will be something...
 
SylentK

SylentK

Turbo Monkey
Feb 25, 2004
2,634
1,084
coloRADo
Hmm...now you guys are getting into details.

Last time I rode a 2.7 DH casing tire (Maxxis DHF meat), it definitely felt like it took the "feel" out of the bike. And because of that I could crush all the rocks, go fast, but couldn't really "feel" the trail as much. Is that good? Depends. For context, DH bike, at Angel Fire, NM DH race.

A 2.5 tire w/ DH casing (DHF, f & r) is my go-to all the time now. On every trail bike. Just cuz it's just easier from a lot of perspectives...I could care less about the weight. Makes for a better work out? And plus you can probably not flat :)

I do like aggressors, dhr's, assguys, too. But if I need a tire and there are none on sale? DHF. Knowing if I get an aggressor, it's only DD. Which is usually fine.

There are "balloon-y" tires. The ones that are thin, light, have lots of volume (Maxxis Recon 2.8). I do actually like these types of tires. You still need to use an insert, bring a tube and tire repair kit. I found them really useful in Sedona and easy trails in Moab. Cuz there's not a whole lot of knob, but still has good traction for the slick rock and hard pack in that region. And rolls fast. For context 29er endurbro machine 160mm of rear. BUT see above for my lack of fondness of inserts and tubes these days. If you have the patience, for sure give it a shot. I had a great time.
 
troy

troy

Turbo Monkey
Dec 3, 2008
1,026
785
saruti said:
And still there is air that will bounce back any hit.
Click to expand...
A galon of Stans should do the trick. No air = no bounce = no 2nd hits = no flats = no problem. 100% tire sealant infill. You heard it here first.

:monkeydance:
 
kidwoo

kidwoo

Artisanal Tweet Curator
Aug 25, 2003
42,149
13,358
Squirtin ketchup n' mustard on charred flesh
saruti said:
Sorry. I got confused between pattern and casing.
Anyway, both not for damping.

Thanks Troy for the tannus insert picture.
But, this tube will inflat forever. And push the insert and make it harder. And still there is air that will bounce back any hit.
If the tube will stop at a size, like the procore. And hold the insert at place, with 100psi, and lets say you can buy inserts with feel of:
20psi
22psi
And so on...
It will be something...
Click to expand...
tire casings absolutely have a damped absorption quality over chatter that suspension would never be able to keep up with

haven't you ever noticed how different chatter feels over fast rough stuff on a cold day? Difference between dh tires and pinner little lightweight ones?
 
Westy

Westy

the teste
Nov 22, 2002
55,921
21,952
Sleazattle
A simple explanation of a tire on suspension performance can be seen as a dual spring mass system. This is potentially undesirable as the two springs will behave differently and can be out of phase of each other, the suspension having a delayed reaction to the tire. There are ways to get this to perform more like a single spring damper. You can tune the performance of the tire to behave exactly like the shock, but this would require significant damping in the tire and the same spring rate and travel. The other way would be to have the mass of M1 equal to zero, not feasible but this is why reducing un-sprung weight improves suspension performance. Most of that weight on a bike is the wheel itself. So all things being equal a wheel with a heavy Onyx hub and a cheap dinner plate sized 12 speed cassette isn't going to work as well as a lightweight hub and say a small lightweight DH cassette.

But the reality is that the unsprung mass of a suspension is already significantly less than the mass of the bike and rider so the overall impact to performance is small.

1704772530081.png
 
kidwoo

kidwoo

Artisanal Tweet Curator
Aug 25, 2003
42,149
13,358
Squirtin ketchup n' mustard on charred flesh
Westy said:
A simple explanation of a tire on suspension performance can be seen as a dual spring mass system. This is potentially undesirable as the two springs will behave differently and can be out of phase of each other, the suspension having a delayed reaction to the tire. There are ways to get this to perform more like a single spring damper. You can tune the performance of the tire to behave exactly like the shock, but this would require significant damping in the tire and the same spring rate and travel. The other way would be to have the mass of M1 equal to zero, not feasible but this is why reducing un-sprung weight improves suspension performance. Most of that weight on a bike is the wheel itself. So all things being equal a wheel with a heavy Onyx hub and a cheap dinner plate sized 12 speed cassette isn't going to work as well as a lightweight hub and say a small lightweight DH cassette.

But the reality is that the unsprung mass of a suspension is already significantly less than the mass of the bike and rider so the overall impact to performance is small.

View attachment 206127
Click to expand...




now do aluminum vs plastic hoopz



yes I know it's the same concept of stacked springs, I just wanted to post that well earned pic
 
Last edited:
Jm_

Jm_

sled dog's bollocks
Jan 14, 2002
20,040
10,603
AK
Westy said:
A simple explanation of a tire on suspension performance can be seen as a dual spring mass system. This is potentially undesirable as the two springs will behave differently and can be out of phase of each other, the suspension having a delayed reaction to the tire. There are ways to get this to perform more like a single spring damper. You can tune the performance of the tire to behave exactly like the shock, but this would require significant damping in the tire and the same spring rate and travel. The other way would be to have the mass of M1 equal to zero, not feasible but this is why reducing un-sprung weight improves suspension performance. Most of that weight on a bike is the wheel itself. So all things being equal a wheel with a heavy Onyx hub and a cheap dinner plate sized 12 speed cassette isn't going to work as well as a lightweight hub and say a small lightweight DH cassette.

But the reality is that the unsprung mass of a suspension is already significantly less than the mass of the bike and rider so the overall impact to performance is small.

View attachment 206127
Click to expand...
Well I for one see resisters and capacitors.
 
Westy

Westy

the teste
Nov 22, 2002
55,921
21,952
Sleazattle
Jm_ said:
Well I for one see resisters and capacitors.
Click to expand...

There is a direct equivalence between analog electrical circuits and mechanical systems like that but the symbols are completely different. A damper is the same as a resistor, a spring the same as a capacitor, inductance is mass, current is velocity, and voltage force, or something very similar to that. Although the reality is neither actually behave in a linear manner and a mechanical system even less so than electrical. Those models assume linear damping which requires a complex damper that is never truly linear and springs are assumed to have no mass, that probably doesn't matter much for bike suspensions but at higher frequencies like in valve springs it causes them to do some crazy shit.

 
kidwoo

kidwoo

Artisanal Tweet Curator
Aug 25, 2003
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Westy said:
There is a direct equivalence between analog electrical circuits and mechanical systems like that but the symbols are completely different. A damper is the same as a resistor, a spring the same as a capacitor, inductance is mass, current is velocity, and voltage force, or something very similar to that. Although the reality is neither actually behave in a linear manner and a mechanical system even less so than electrical. Those models assume linear damping which requires a complex damper that is never truly linear and springs are assumed to have no mass, that probably doesn't matter much for bike suspensions but at higher frequencies like in valve springs it causes them to do some crazy shit.

Click to expand...
four strokes are the spawn of satan

this video confirms
 
mykel

mykel

closer to Periwinkle
Apr 19, 2013
5,464
4,194
sw ontario canada
Westy said:
There is a direct equivalence between analog electrical circuits and mechanical systems like that but the symbols are completely different. A damper is the same as a resistor, a spring the same as a capacitor, inductance is mass, current is velocity, and voltage force, or something very similar to that. Although the reality is neither actually behave in a linear manner and a mechanical system even less so than electrical. Those models assume linear damping which requires a complex damper that is never truly linear and springs are assumed to have no mass, that probably doesn't matter much for bike suspensions but at higher frequencies like in valve springs it causes them to do some crazy shit.

Click to expand...
So, that is what my valvetrain looks like. Surprised at the amount of rotation. Kinda cool.
 
Westy

Westy

the teste
Nov 22, 2002
55,921
21,952
Sleazattle
kidwoo said:
four strokes are the spawn of satan

this video confirms
Click to expand...

In modern engines that is really only a problem with dumb old pushrod 2 valve engines. Smaller valves from a 4 valve setup are lighter and require lighter (faster) springs. A poppet valve can also flow more air and control it's timing allowing you to make torque at more than on specific RPM. Or you can go full retard with a springless Ducati Desmodici setup.
 
Westy

Westy

the teste
Nov 22, 2002
55,921
21,952
Sleazattle
I take it back. Tire deflection completely fucks up suspension performance I am willing to design and sell at high costs a tunable air damping cartridge you can mount on a wheel's air valve like the dampers on old White Brothers XC forks. Guaranteed to be 100 times more effective than damping stickers. It would also provide a more linear coil like performance from your tire.
 
kidwoo

kidwoo

Artisanal Tweet Curator
Aug 25, 2003
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Squirtin ketchup n' mustard on charred flesh
Westy said:
I take it back. Tire deflection completely fucks up suspension performance I am willing to design and sell at high costs a tunable air damping cartridge you can mount on a wheel's air valve like the dampers on old White Brothers XC forks. Guaranteed to be 100 times more effective than damping stickers.
Click to expand...
but......does it feel like a coil, a thing I've never owned but have read about extensively?
 
Westy

Westy

the teste
Nov 22, 2002
55,921
21,952
Sleazattle
kidwoo said:
holy fuck.....I'll be selling these to idiots in a month

I'll split the profits with you. thanks!
Click to expand...

Sorry, I already have prior art and a have submitted a patent application for V2 which uses activated carbon to increase the effective volume of the tire. 2.0" rolling resistance with 2.4" plushness!!!!!!
 
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