Suspension tuning, HSC vs LSC

So I was browsing some threads on RM last night. Some of the posts absolutely turned my thinking on suspension tuning upside down. Specifically Craig from Avalanche and his philosophy on HSC vs LSC.

So from what I understand, he prefers lots of LSC, whereas most people don't like a lot of LSC because it screws up their idea of plush. I admit, I was in this camp, where I used very little LSC. I would do my parking lot test, set my LSC, make sure it was plush while I was riding so that I wouldn't feel most fist sized rocks, and give a few clicks of HSC. Then I would make sure I used most of my travel on every ride and call it a done day.

I've always felt like my bike dove through its travel too much on braking. I just felt like that was a function of plushness and efficiency. Now I'm reading some of these threads where people prefer a lot more LSC, because it prevents these geometry changes and allows you to ride higher in the travel. People were saying it failed the parking lot test, but traveled through the chop a lot better.

So basically what they were saying was even for drops, most drops with good transitions are LS. Only fat drops to flat would be considered HS. Small bumps, at speed, would be considered HS. Rocks at speed, would be HS.

What are your guys' thoughts? Im going to be testing this out this weekend. Unfortunately my Roco WC has not separate adjustments. My 66 RC2X does.

 

Good post. I too, only have LSC/HSC damping on my fork (Lyrik) and set the LSC fairly high, while using using very little HSC damping. I initially used more HSC and less LSC, but find the ride plusher with the newer set up.
I think a lot of people struggle with the differences between the two, but with a little thought and experimentation, more people would appreciate their suspension's capabilities.

 

i use moderate lsc just enough to not dive but not so much it is chatters in corners, highspeed is usally pretty low so the bike settles in to the corners right

 

I used to run very little lsc with the same thought of more plush. Then I was schooled by a suspension guru on settings..
now I run very high LSC and just enough HSC to use all my travel. With this set up. I'm able to rail coners and brake very aggressively with out dumping the front fork. And you are correct in saying that all your bumps small and big at speed goes through the HSC. The only time you will notice a rougher ride with a higher LSC is when your going slow and not hitting the bumps fast enough to hit the HSC.

play with it.. That's what it comes down too. Also each trail needs it's own setup if they are extrem terran differences.

$ .02

 

The thing is, I think most bikers tune OPPOSITE of this. However, MX guys have been doing this for years. That's why if any of you have ever played around with a dirt bike in a parking lot, they kinda feel weird, but at speed, it handles the chop no problem. Can't wait to try it this weekend, and now I really have to send off my 5th Element to Craig so I can have my separate LSC and HSC adjustments.

 

Hmm all this talk about LSC has me thinking...is it possible to set the Pike's floodgate/lockout settings to work like a low speed compression adjustment?

 

Here's how I think about it:

LSC: deals with weight transfer, as in a car. When you corner and the car rolls, the CG is shifting towards the side of the car on the outside of the corner. The better you control the weight transfer (body roll), the more mechanical grip you can produce. On a bike, there is less shifting of the rider's CG over the bike + more force pushing the knobs into the dirt for traction.

HSC: deals with "jounce", allowing you to adjust how sensitive your suspension is in responding to objects on the trail, not rider weight.

Anything a rider can do in transmitting force to the bike is LSC related, Trail transmitting force to the bike is HSC related. That being said, I trashed the metacarpals in both of my hands last summer riding Whistler with lots of LSC.

 

One thing I learned is that parking lot test and suspension tuning shouldn't be said in the same breath.

I even stopped doing the "just riding along and compress hoppidy hop" thing you see guys doing before races/rides.

I do one click, ride and try to feel what the fork is doing.

 

Tuning Guide

Rock Shox has a great tuning guide on Mission control that covers both High and Low Speed compression settings, and gives you some great starting points for the type of riding that you are doing

http://www.sram.com/_media/pdf/tuning_guides/missioncontrol_tuningguide_en.pdf

 

i like to bounce for about 10 minutes in the parking lot...and then hand my bike to drake (isotune) so he can tune it lol.

 

Holy Carp! I just tried reversing my settings on my Fox36 TALAS (Yeti 575) and I noticed a difference almost immediately (I weigh 210). I turned up the LSC five clicks (from 0), and pulled down the HSC from 5 to 1 and noticed that the little trail chatter at slow and moderate speeds disappeared! I was stunned - and maybe I am imagining it. Big hits were fine, and no noticeable difference in brake dive (never seemed to be a problem). I'm gonna try the same thing on the big bike tomorrow.

To think differently about the settings, I have re-named them in my mind. For me LSC now refers to deep, low frequency compressions (drops, chunk and G-outs), and HSC refers to shallow, high frequency compressions (stutter bumps, trail chatter, little rocks). Thanks for the tip! :beer:

Are you saying your injury was an over-use injury cause by your suspension settings? That's harsh... How many runs were you taking a day, on what kind of trails?

 

awesome. im glad it worked for you. im telling you, this goes against everything i have heard from fox/rock shox manuals and what people have recommended. just look at the mission control tuning guide. it specifically talks about lsc as for small rocks. it has no mention of shaft speed. i never even tried to add lsc and decrease hsc because everything said to increase small bump sensitivity, you had to lower lsc.

 

In my experience manuals arent written by engineers...as an engineer im baffled by manuals, marketing information, "tech" articles etc...

 

as engineers, you and i both know the last person you want writing a manual is an engineer. lol. id rather a rider write it so the masses can understand, versus an engineer writing it so that only other engineers understand how the internals work but have no idea how that translates to riding, and thats only if they can get past the grammatical and spelling errors.

 

Low speed compression damping usually controls rider input: brakes, pedal bob, pushing off for a J-hop, shifting in attitude etc. Enough low speed compression will not feel plush enough to some when just pushing down or bouncing around.

High speed compression generally controls bumps and drops.

I am not sure which controls smoother G-outs, but I imagine it depends on the situation.

 

It sounds like you are really on the right track to me.

 

Any thoughts on whether or not the 66RC2X has a true HSC and LSC adjuster?

 

Get an avy cartridge like. Ihave and craig puts a mid speed flutter stack in it to keep it from havingbrake dive with no effect o. High speed settings or low speed tuning. Mxrs have been doing it for a long time and avy cart rocked sit, intense, Tod, skinsuit,and. Ted Williams over the last 4 days. Absolute monster fork.

 

Garrett, the compression knob on the Pike is your low speed compression, and the gate is the knee adjustment for the high speed damping. Small gate adjustments can change the high speed damping characteristics, but too much gets spikey real fast. The true high speed damping is fixed through the size of the orifice in the MoCo cartridge, and the stiffness of the MoCo spring tube. It would be great if Rock Shox would produce a DH damper for the Pike.

I run 5 clicks of Floodgate, and my compression adjuster about halfway closed. Keeps the fork from wallowing, but still pretty supple.

 

You wanna convince him to have me be the guinea pig for the single crown long travel forks?