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High speed compression adjuster: benefits and downside?

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OK, I know if you turn the low speed compression adjuster in it makes the ride firmer, what does turning out the high speed compression adjuster do? Why wouldn't you just turn it all the way in to prevent bottoming? :thumbsup:

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yeah good question,no magazine settup guides ever refer to the high speed adjuster,i'd be interested to know how it affects the ride

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sounds easy, stiff high speed - no bottoming. unfortunately jumps are more mid-speed, so both (high- and low-speed) affect bottoming resistance a little.

stiff high-speed causes a harsh feeling when you hit square-edged bumps, so you can turn it in when you ride on sand or the caterpillar removed all the bumps out of a hard terrain track

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The comp adj. is a fairly simple device that allows oil to flow in two paths upon demand. The low speed circuit flows at all speeds and is simply an orifice metered by a tapered needle. Once the capacity for flow through this circuit is maximised, pressure builds and opens the high speed circuit. The high speed consists of a shim stack backed up by a spring. By tightening your H/S adj you apply more preload to the spring creating greater resistance across the high speed shimstack. The further your L/S is open the later your H/S comes into play. The more it is closed the earlier the H/S activates.

I like to run the adj at 1 1/2 turns out on the H/S and 14 clicks out on the L/S as a baseline. Obviously you can adjust to suit.

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The comp adj. is a fairly simple device that allows oil to flow in two paths upon demand. The low speed circuit flows at all speeds and is simply an orifice metered by a tapered needle. Once the capacity for flow through this circuit is maximised, pressure builds and opens the high speed circuit. The high speed consists of a shim stack backed up by a spring. By tightening your H/S adj you apply more preload to the spring creating greater resistance across the high speed shimstack. The further your L/S is open the later your H/S comes into play. The more it is closed the earlier the H/S activates.

I like to run the adj at 1 1/2 turns out on the H/S and 14 clicks out on the L/S as a baseline. Obviously you can adjust to suit.

Ok I sort of understand. It seems like the more the L/S is closed the LATER the H/S should activate. :thumbsup:

I was just wondering b/c I don't really have a bottoming problem, yet, and I figure if i'm not bottoming or coming close, shouldn't I turn out the H/S compression? :ride:

thanks~

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That's backwards, because the more the LS is CLOSED, the earlier the HS will activate.

Think about what Terry posted...

After the LS can no longer flow out of, the pressure built up then pushes against the shims of the HS.

If you shut off the LS clicker, then the flow immediately proceeds to the HS circuit.

That was an AWESOME explanation of the H/L speed clickers! Reception came in crystal clear!

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So if the suspension feels great landing off of jumps, no bottoming just nice and soft, but feels like there is no suspension at all on breaking bumps and high speed chop, would I adjust the H/S or L/S or both? OR would this be more of a rebound thing?

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Perhaps it would help some to think of them as Hi Pressure and Lo Pressure adjustments.

You can't get to a higher pressure without first passing through a lower pressure.

:thumbsup:

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Perhaps it would help some to think of them as Hi Pressure and Lo Pressure adjustments.

You can't get to a higher pressure without first passing through a lower pressure.

:thumbsup:

Probably the best explanation Ive ever heard...

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Kliss

Damping will be predominately controlled by the piston shimstack and only a smalll portion controlled by the adjuster. It seems to me that your shock is too stiff overall. Remember, the force of the impact will take the path of least resistance. If it is physically easier to push the rider around, than compress the suspension, then this is what will occur.

Post your details and it will provide relative info to your situation

Weight

Bike

Sag

Clicker positions

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Im around 155-160 without gear on, never weighed myself with gear on and I dont know how much it all weighs. I have an 06 CRF450. Havent set my sag yet, Ive been meaning to do that just never get around to it. Havent measured what it is right now either. Ill go and do that tonight and tell you what it is, Ill probably set it to what is should be while Im at it. I havent touched any of my clickers yet either.

Like I said, i feels great landing off of jumps but on braking bumps or some high speed chop it feels like hell. There is a natural terrain step-up around here that doesnt really have a downslope landing just the flat top of a hill and landing off of it the suspension feels good but it is pretty rough leading up to and I just get thrown around. It doesnt look like it should be as rough as it feels. Its kinda like whoops but not very tall and spaced apart. I hit it in 3rd about 3/4 throttle going up to it and pin it about 5 feet before the lip.

This question is a little of topic but I ride mostly tracks would I set my suspension different accordingly?

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Kilss you are indeed too light for that bike. For now try the following.

Set the sag to 105mm

Shock

H/S 2 turns out

L/S 20 clicks out

Rebound 10 out

Forks

Compression 20 clicks out

Rebound 16 out

Remove 15ml of fork oil from each leg.

To do this remove forks from bike. Invert for a minute or so. Remove air bleed screw and pump out 15 mls into a beaker or suitable measuring device.

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Remove 15ml of fork oil from each leg.

To do this remove forks from bike. Invert for a minute or so. Remove air bleed screw and pump out 15 mls into a beaker or suitable measuring device.

Now that is a great idea!

By inverting the forks, the outer fork oil transfers into the inboard cartridge via its dual bleed holes. Then the fluid has a straight path out out of the forks through the air bleed screw. :thumbsup:

Conversely,

I know that others here have posted about adding fork oil, also through the air bleed holes, on the TC forks. I've tried it but found an annoying problem with this. For whatever reason, my forks initially get WAY stiff, even at 5cc added, when I inject it through the air bleed holes. If I pour 5 cc in the outer chamber after unscrewing the top cap off the upper tube, I don't feel any stiffness.

Haven't figured out what the deal is with that. But if I had to guess, I think the added oil is keeping the IC piston from sliding up the inner cartridge...marginally slight no doubt, but who know...just a little could be all that it takes to effect some sort of oring stiction.

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Alright Ill give that a shot and see what happens. Would anything change for riding tracks?

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Kilss

Ultimately your springs and valving need to change. This is only a stop gap to help improve your current predicament.

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alright, I hope it works I dont exactly have the money to have somebody redue my suspension right now, effin school.

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are those settings from all the way soft or hard?

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are those settings from all the way soft or hard?

Kinda hard to go 20 clicks out from all the way out, right? Turn them all the way in and count going back out... :thumbsup:

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With regards to this adjustment and tuning has anyone tried using the Factory connection - High Speed Compression Adjuster Springs?

http://www.factoryconnection.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=FC&Product_Code=HSCOMPSPRINGXX&Category_Code=FCSHKP

For $15 I was wondering if they were worth it to install while the shock was apart for an oil change?

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I have one installed. As of late I have been struggling with my shock. FC revalved my rebound for me to slow it down a little and I went one unit + on the spring because I had too much preload.

The Shock is harsh and so I have made a few calls to FC: I basically throw my back out on every type of hit.

They insist that I should keep the HS backed out to 3 with their spring in there. When I get back out I am going to experiment more with turning in the HS and turning out the LS compression.

I have researched and found all kinds of theory on HS. The funny part is when I read about someone going against theory and turning it in to keep the shock from blowing through and then tayloring the LS and Rebound. I am no longer going to beleive that you can not have a plush ride with your LS turned in slightly.

I also think it's funny how (I am not excluding myself) people put on offset clamps and experiment with fork height and don't pay attention to the HS more.

One day I will buy a factory shock for $$$$$$ so I can have all the circuits be completely separate. In the meantime I will keep asking the gurus for help.:ride:

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