HSC again.......sorry guys I'm confused

[flynbryan]

Guys I tried pulling up a search on High Speed Compression before I asked for your knowledge again, but I just got confused by the results I've found. I'm trying to dial in my suspension for chop and fast shaft speed obstacles(square edge objects, ie: roots, rocks, hard pack chop holes) Marcus I know you and I dabbled in this slightly a few months ago. Basically to eleviate the confusion(I hope :ugg: ) I would like to know what circuit affects sudden/short travel useage. My initial thought process leads me to believe it would involve HSC where the suspension is returned to its prior state quickly using up only a short distance of the shock travel. LSC involving landing from large jumps and G-out situations where you use a great distance of travel. Thanks in advance for any of your replies

 

[Jeff Howe]

For the most part you are correct. But the LS adjustment can affect HS. LS adjuster is needle/orifice and the HS adjuster is spring tensioned shim stack. Fluid will take the path of least resistance so, by design you can see that at lower fluid velocity it will pass through the LS orifice until enough velocity is achieved to "lock up", then the force will be working against the spring tensioned shim stack. Working these 2 adjustments with this in minds yields better results once you get the hang of it.

 

[bclapham]

i messed with my HSC also and it took ages for me to sort it out.
this is for the tuners, is there anything to what the mags say about setting the HSC, ie turn it in (stiffer) to make it ride higher in the rear and out to make it ride lower in the rear?

too many dials more me, i wonder if the other manf. will follow kawasaki and chuck the HSC adjuster?

 

[marcusgunby]

The main problem i see is the adjuster doesnt actually alter high speed that much-more mid speed, your problem should be improved by getting the right HSC and LSC setting-however as Shocknut states this isnt easy to do.The best adjusters are the ones that are totally separate on the shock-like a works Wp has.

 

[flynbryan]

Thanks again guys. I thought I had the right thought process I just wanted some more outside(read:experienced)opinions. I'm having more of a problem w/the forks responding in a harsh nature rather than the shock though. Unfortunatly I have no HSC adj. on my forks:( So I'm hoping that my forks will get better w/a long over due fluid replacement. Thanks again:thumb:

 

[Robcolo]

Bryan, The harshness on sharp square edged stuff is [usually] due to too much HSC. Since that's not externally adjustable, you have to remove a shim or two from the HSC valve stack. IF this is on you'r crf450, there is an entire article in a recent issue of DIRT RIDER mag where [I believe] Pro-Circuit re valved that fork and remarked that it was "horribly confused" from the factory. They increased the LSC because the fork was settling down too much and becoming harsh. They also decreased the HSC --and decreased the spring rate.

 

[flynbryan]

Yea I've had a problem w/ getting the front end on my bike(yes the CRF)to compress in the corners. And now that I ride trails its been an even bigger headace w/the forks being so harsh. I'm not certain if its from just a resistance to initial movement or if it is indeed settling TOO MUCH into the travel and hitting the midstroke so that I'm getting a spike. Any ideas guys? I really think I'm in the weight ballpark at 170lbs. before gear for the springs.

 

[Robcolo]

That pro-circuit CRF450 article was in DIRT RIDER Dec. 2001 issue.

 

[flynbryan]

Thanks Robcolo, I think I actually have that issue sitting at my house;) I really think alot of the harshness has to do w/old suspension fluid. I'm going to get it changed here real soon and I think that will help alot.(ps its the original fluid!:eek: )