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#81 ·
RickBullottaPA said:
Here's the companion to Motion Instruments for suspension analysis - BrakeAce with a focus on brake telemetry and performance analysis:

https://www.brakeace.com/
Click to expand...
Matt (BrakeAce) and I spent a day with one of our top enduro racers late last year, this is a POV from the day with data overlay-
Red=Front Brake Blue=Rear
There wasn't room for a velocity trace so here is the front and rear damper speeds-
 
#82 ·
Dougal said:
No way a 700/400lb spring in a car can be comfortable. That's a 2.2x increase in ride frequency. It'll be jiggly and incredibly harsh no matter what the damper is.
Click to expand...
Its all about the quality of the shocks man. Penskes/Motons/ASTs/Hand fitted Bilstiens, ride much nicer than mass produced billies, showas, konis, etc, and they need the right valving for the spring rates, corner weights, and unsprung mass. They certainly ride like a performance car, you can feel the road, but its not harsh or painful, you never wince hitting a bump.
 
Discussion starter · #83 ·
EatsDirt said:
You sure about that? Closing the HSC on my fork would have it so firm it would rattle fillings out.
Click to expand...
What is your fork and how do you have it set?

I ran a Charger 2.1 RC2 in a Lyrik with 60psi and 2 tokens. I weigh 70kg plus gear. No problem riding it and getting full travel with LSC and HSC wound closed.

It's a terrible damper tune like that. But many people are riding worse.

I run 2.6" DHF front tyres at 25psi also.
 
#84 ·
upsha said:
Actually, 3.4m/s is the "average vertical speed" over the whole duration of this single square hit in discussion. The peak speed within this event must be higher, even considering tire. It's explained in The Tuesday Tune Ep 16. You can jump to 2:15 to see the drawing from Steve and the comparison to "average speed" starting 5:57.

Click to expand...
I know ;) just helping to illustrate the point that the actual peak speed will always be lower than the theoretical peak speed (eg assuming a rigid tyre and no movement at the bar)

It also helps to remember there will always be some kind of acceleration at the handlebar, so you are better off starting to lift the bar early and gradually than in the situation of too little damping where the bar doesn't start moving until near the peak of the bump and creates much higher acceleration (read:pain) for the rider.

Allow the great Paul Thede to illustrate it better than I can-


Dougal said:
They fixed the LSC needle sizing issue between C2 and C2.1. The C2 RC2 LSC was a complete waste of time. It just moved a plunger up and down a few mm in an oversized hole. C2.1 isn't much better but at least it can close.
Click to expand...
Um, no they didn't...the hole and needle got slightly smaller and a fractionally different shape but it has the same clearance to the inside of the bolt. Did you actually take one apart properly?
Top needle + bolt is from a charger 2.0 RC showing the old large needle fitting inside, the bottom is a charger 2.1 rc2, slightly smaller but still fits inside
 
Discussion starter · #85 ·
JohnnyC7 said:
I know ;) just helping to illustrate the point that the actual peak speed will always be lower than the theoretical peak speed (eg assuming a rigid tyre and no movement at the bar)
Click to expand...
The more heavily damped you are, the lower speed you can attain.

JohnnyC7 said:
Um, no they didn't...the hole and needle got slightly smaller and a fractionally different shape but it has the same clearance to the inside of the bolt. Did you actually take one apart properly?
View attachment 1322587
View attachment 1322589
Click to expand...
Jono old boy. That's an RCT3 you're showing there. Not an RC2.

Yes I've taken them all apart, measured them and have the geometry recorded in 3D CAD. I've also ridden them all to confirm the functional difference.

The hole got smaller, the needle didn't. They now close.
 
#86 ·
Dougal said:
Jono old boy. That's an RCT3 you're showing there. Not an RC2.

Yes I've taken them all apart, measured them and have the geometry recorded in 3D CAD. I've also ridden them all to confirm the functional difference.

The hole got smaller, the needle didn't. They now close.
Click to expand...
It's a charger 2.1 RC2. I don't even own an rct3.

I've taken it apart, measured it, DYNO'd it, and ridden it
 
#87 ·
I gotta ask

in general

if no one likes the stock damping, then who are the fork/shock makers building these for ??? I have a 1000 dollar fork, on day one, it's full of potatoes then ?
 
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#88 ·
127.0.0.1 said:
I gotta ask

in general

if no one likes the stock damping, then who are the fork/shock makers building these for ??? I have a 1000 dollar fork, on day one, it's full of potatoes then ?
Click to expand...
The people who just buy the bike they think want without really riding it and just assume that sram/rockshox make an acceptable product? Like they still keep making forks with motion control, people have hated that for a decade, but it probably only costs them $6 all in for the compression part of the damper unit and people keep buying them so they dont have a reason to change. Hopefully the Z2 forks pretty much immediate success will at least force them to **** can the moco revelation as more and more bike manufacturers seem to be replacing revelations with Z2s in their lineups.
 
Discussion starter · #89 ·
JohnnyC7 said:
It's a charger 2.1 RC2. I don't even own an rct3.

I've taken it apart, measured it, DYNO'd it, and ridden it
Click to expand...
Time for a coffee and to re-read the laser etching on your fork caps. Because that picture is the RCT3.
The RC2 does not have the lockout rod with all the holes around it.

Image


The functional difference between the RC2 and RCT3 LSC circuit is the RC2 is a simple needle arrangement so can be made to close in the normal way. The RCT3 is a plunger which moves up and down a lot with that lockout rod so cannot be made to meet a seat because it has to move up and down with each HSC mode.

Picture 3 on this instagram post of mine shows the C2.1 RC2 needle setup. Completely different to your RCT3 pics above.



127.0.0.1 said:
I gotta ask

in general

if no one likes the stock damping, then who are the fork/shock makers building these for ??? I have a 1000 dollar fork, on day one, it's full of potatoes then ?
Click to expand...
Top three.

Fox F36 RC2 is stock good for 90kg guys who ride hard, go big and like to feel every small bump on the trail.
Lyrik RC2 is for those who hate compression damping and like to ride an air spring down the trail.
Manitou Mezzer is stock good for 80kg guys who like to iron out the small bumps.

As a 70kg rider I would ride a F36 tuned to be softer with burnished bushings and luftkappe. Possibly a smashpot.
I would ride a Lyrik RC2 with damper modifications, revalved to be firmer with burnished bushings and probably a smashpot.
I actually ride a Manitou Mezzer revalved to be softer on compression and with experimental mid-valve mods.
 
#90 ·
Dougal said:
What is your fork and how do you have it set?

I ran a Charger 2.1 RC2 in a Lyrik with 60psi and 2 tokens. I weigh 70kg plus gear. No problem riding it and getting full travel with LSC and HSC wound closed.

It's a terrible damper tune like that. But many people are riding worse.

I run 2.6" DHF front tyres at 25psi also.
Click to expand...
170mm Lyrik RC2 90kg (200lbs)
Around 90psi
1 token
HSC 1 in from open (6 total positions? sorry don't do from closed)
LSC 6 or so in from open
2.5DHF around 27psi if it's relative

HSC on two clicks from open makes fork stand up and becomes a bit harsh. There's no way I'd close it any more. Full closed in fast chatter/chunk would be absolutely unbearable.

LSC adjustments don't seem all that effective (can ride fully closed without problem)

I rarely use full travel, fork doesn't dive horribly under heavy braking, and has (from my unedumacated opinion) plenty of support. I figure I'm pushing the bike pretty hard (pic) but no doubt there are others that are heavier and smashing harder.

I might be enjoying a free feeling fork these days as age is catching up, but I don't get how what is supposedly horrible by expert opinion feels so good?

Image
 

Attachments

#92 ·
Dougal said:
Time for a coffee and to re-read the laser etching on your fork caps. Because that picture is the RCT3.
The RC2 does not have the lockout rod with all the holes around it.

Image


The functional difference between the RC2 and RCT3 LSC circuit is the RC2 is a simple needle arrangement so can be made to close in the normal way. The RCT3 is a plunger which moves up and down a lot with that lockout rod so cannot be made to meet a seat because it has to move up and down with each HSC mode.

Picture 3 on this instagram post of mine shows the C2.1 RC2 needle setup. Completely different to your RCT3 pics above.



Top three.

Fox F36 RC2 is stock good for 90kg guys who ride hard, go big and like to feel every small bump on the trail.
Lyrik RC2 is for those who hate compression damping and like to ride an air spring down the trail.
Manitou Mezzer is stock good for 80kg guys who like to iron out the small bumps.

As a 70kg rider I would ride a F36 tuned to be softer with burnished bushings and luftkappe. Possibly a smashpot.
I would ride a Lyrik RC2 with damper modifications, revalved to be firmer with burnished bushings and probably a smashpot.
I actually ride a Manitou Mezzer revalved to be softer on compression and with experimental mid-valve mods.
Click to expand...
Since you couldn't seem to understand what was in the picture, i edited the post to spell it out. Top is C2 RC, bottom is 2.1 RC2
 
#94 ·
Couple more comparisons just to show I'm not on crack

First pic- charger2 RC and charger 2.1 RC2

2 pic, charger 2.1 rc2 side by side will Douglas pic yo show it's the same as mine, plus a photo of the 2.1 needle sliding inside it's bolt, ie no hard stop
 
Discussion starter · #95 ·
JohnnyC7 said:
Since you couldn't seem to understand what was in the picture, i edited the post to spell it out. Top is C2 RC, bottom is 2.1 RC2
Click to expand...
JohnnyC7 said:
Couple more comparisons just to show I'm not on crack

View attachment 1322673 View attachment 1322675
Click to expand...
That top picture shows a RCT3 beside a C2.
That middle picture is my C2.1 RC2 picture.

Here is the RCT3 damper cutaway:

Here is the RC2 cutaway:

The differences they made from C2 to C2.1 in the RC2 to ensure LSC closes cannot be seen in your pictures either. It's a small change in bolt ID.

I have no idea what you're doing with this or why you've got it so wrong.
 
#99 ·
Leafy1 said:
Darren could you post some football plots or just normal damper plots without adjusting the zero point?
Click to expand...
As requested. Below is the same test run on a stock C2.0 and stock C2.1.

Test:
Fixed velocity 15in/sec (0.381m/sec)
LSC: Sweep of 0-18 clicks out
HSC: Full Firm (Closed)
Rebound: 10 clicks out from full closed



Enjoy!

Darren
 
#100 ·
JohnnyC7 said:
Matt (BrakeAce) and I spent a day with one of our top enduro racers late last year, this is a POV from the day with data overlay-
Red=Front Brake Blue=Rear
Click to expand...
What I find strange is at about 2:58 which seems to be the only time the front brake is applied strongly. And even then, it seems to be at about the quarter of the force that rear brake actually sees.

Is this simply showing that the rear brake has to be applied 3/4 times as hard to have any effect?
Arguably the rear brake in the video is being used to 'steer' more than slow the bike down. Which I have no doubt professional riders do all the time. Who doesn't feather the rear brake when mid corner when you've come in a little hot.
I guess which would wear pads more? Hard short bursts, or light frequent dragging?
It would be cool to see something similar down a really steep WC DH track.
 
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