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anyone familiar with 5th elements??

Sov

Chimp
Jan 1, 2008
73
19
Adelaide, Australia
Hi, first post:) Just thought that I'd mention that this thread and the 5th hottie one have been a great read.

I just rebuilt the 5th on my SC Heckler today using a 70 duro Buna shaft seal and Fuchs shock oil (11cst @ 40 deg C - really light.) I had to do it twice as my first build had a bit of air in it, but it worked out ok doing it in an oil bath second time around.

I'm 140lbs, run a 300lb spring on a bike with a 2.45 leverage ratio. I used to run the stock 5th wound out all the way (LSC/HSC/LSR) with 60psi in the reservoir and still felt that it was overdamped. With the lighter oil, the compression adjusters feel a whole lot more useful now, and the softer seal has reduced stiction heaps, so I'm really happy.

The low speed rebound still feels a touch slow though - I'd like to be able to set it too fast if possible. I had it rebuilt here in Australia by Neezy some 18 months ago and asked them to open up the low speed rebound a touch, so I'm not sure if my internals are standard (is there a standard?) I have the following disc stack on the rebound side of the piston:
- One 12x0.1mm deload disc (piston had 0.25mm of preload)
- Two 18x0.15mm discs
- Two 12x0.1mm discs
- One 11.5x1.5 washer
...then the piston bolt.
I thought that perhaps I could deload the disc stack on the piston bolt head as it looked to be running a fair bit of preload but could not get it undone. So perhaps next rebuild I might run two 12x0.1mm discs as deload (0.5mm preload should provide adequate sealing I think) or maybe add a rebound bleed disc.

Was just wondering if anyone knew the answers to these questions:
- Do all 5ths have the same reservoir size? I set the IFP at 39mm with the rod extended. Should be 40mm by my calcs using info earlier in this thread. It was set to 38mm before I tore it down.
- What is the torque setting for the piston bolt? I want to make sure that this is tightened correctly seeing as it withstands the top out loads!
 

dhkid

Turbo Monkey
Mar 10, 2005
3,358
0
Malaysia
I've got a 2005 DHXc that probably needs an oil change. Any idea on the type of oil in that shock or what the IFP depth is supposed to be. It's a 7.5" X 2" off my RFX.

the stock oil used in it is torco 10wt. i just use silkone 10wt, but my shox uses 7.5 wt for faster rebound purposes. i think the ifp depth on a 2.75x8.75 shox is 34mm. sorry, i dont know them, i always measure the end cap maximum length then add a few mm for the ifp depth at bottom out.

i remember someone posting the info in this thread. its a long read.
http://www.ridemonkey.com/forums/showthread.php?t=163201&highlight=dhx


sov- cant help you there, you will have to wait for the guru.
 

-Danno-

Chimp
Jan 31, 2006
39
0
The low speed rebound still feels a touch slow though...
I'm heavier than you, my Bullit has a bit higher leverage ratio, and I'm running about the same oil weight that you are in one of my shocks, but I still find the LSR a bit slow. And that's with the adjuster wide open. I haven't done any real riding yet with this setup though so I won't be making any changes until I really try it out.

If the LSR really is overdamped it makes me wonder if the HSR might need tweaking too. I believe that all four 5ths that I pulled apart had 4 large HSR shims on the main piston. Does it make any sense to trying building it with only 3?

As for LSR, two of my shocks had 2 large shims against the piston bolt, then 2 small, followed by the C-clip. The two others I had apart had an allen bolt holding the shim(s) on. I didn't pull that bolt out though so I don't know exactly how that setup worked.

It's tough to feel when HSR and LSR crossover to know which shims to modify. I certainly feel that LSR is a bit slow since the adjustment is wide open, so I will modify stack, but should I also pull an HSR shim while I'm in there?

I figure that the shimmed rebound circuits must be tuned to match the CV compression damping at some average pressure. I'm running ~60psi, which I'm guessing is below that average. The 350lb spring I'm using is probably on the low end as well. This makes me think that is might be worth reducing rebound across the board to prevent packing. Does that make any sense?
 

-Danno-

Chimp
Jan 31, 2006
39
0
I just modified one of the shocks to have

HSR - Removed one of the shims
8 X 18 X 0.13
8 X 18 X 0.13
8 X 18 X 0.13

LSR - Only one large diameter shim now
6 X 15 X 0.1
6 X 10 X 0.1
6 X 10 X 0.2
Clip

Stock weight oil.

The rebound is quicker, but I haven't ridden the bike yet.
 

dhkid

Turbo Monkey
Mar 10, 2005
3,358
0
Malaysia
i was trying to find the post where mttytee posted the sunday tune rebound configuration.

cant remember it precisely. i know it was one small shim, the on of the big shims, then another small shim, and then the other 3 (or two) big rebound shims.

sorry for the nice detailed technical description, but i hope you get what i mean. its basically one shim at the bottom to reduce the preload of the whole stack, so it would let oil flow easily at lower speeds, then when is bends enough it would touch the other big shims at higher speeds.

a two stage shim stack. god i am crap with words.

anyways, my main rebound shim stack has these two other smaller shims, which were put on top of the shim stack and not doing anything. those were used in between the big shims. my lsr stack had only one preload shim and one big shim. so the 5ths that you guys have must be different.

one more thing, you dont actually have to think of when you want to speed the LSR up it has to be done on the LSR stack. it can be done on the HSR stack. just think about other shimmed shocks, compression, both low speed and high speed is done by the same stack.

edit: forgot to say what actually works for me. i tried the sunday tune rebound and still found it not fast enough for my liking. i just ended up putting all the small shims under the big ones, its fast now. yet to test it enough to say whether i am happy with it.
 

-Danno-

Chimp
Jan 31, 2006
39
0
dhkid, It does sound like you have different shims then I do. All my 5ths are not the same though.

I'll have to try a few different shim configs to see if I find one I like best. Certainly, I wanted to reduce LSR somewhat. I don't know if the HSR needed reducing, but since the damping seemed a bit to high all around I figured it couldn't hurt to pull one of the four shims. What I did kind of goes against the 'change one thing at a time' concept though. :bonk: The good news is that now it only takes me about 1/2 hour to reconfigure the shims.

I'd think if I tried to speed up LSR using the stack on the main piston I'd probably be taking out way too much HSR. I'm a total noob at this stuff though so I'm still trying to get a feel for it.
 

dhkid

Turbo Monkey
Mar 10, 2005
3,358
0
Malaysia
what i am trying to explain to you is that you dont have to think of it as in LSR shim stack and HSR shim stack.

think of it this way, if you took all the shims out. whats left is two holes (of course the HSR circuit has more holes but just call it one big hole), the proper name for it would be orifice. now the LSR circuit has a much smaller orifice then the then HSR circuit. at the volume of oil moving through each increases, the lsr circuit will reach a maximum volume flow rate and spike much earlier then the HSR circuit. thats what they are called LSR and HSR circuits, becuase the LSR circuit can only handle the smaller volume flow rates (low shaft speeds) but the HSR circuit can handle much higher flow rates and thus speeds.

BUT, this doesn't mean that the HSR circuit cannot handle the low volume flow rates. you can think of shims as something that is controlling the size of orifices, the more force you put on them, the bigger the orifice becomes. so in theory, the size of the orifice will vary from fully closed (metering low volume flow rates) to a fully open one, and what controls them is the shims.

you can close off the LSR circuit and reshim the HSR circuit to your needs. the reason the LSR circuit is there is because it is a way so that rebound can be adjusted externally. and this shims are there mainly to act as a one way valve, so that your rebound setting doesn't effect your compression setting.

you should do some reading on how shims work.

i hope that makes sense.


as for having different shims, it sure does wound like it. your control valve, does is it cylindrical shape or bowl shaped? if its cylindrical shape that means its the older model, different from what i have.



mttytee, feel free to correct me where i have gone wrong.
 

Sov

Chimp
Jan 1, 2008
73
19
Adelaide, Australia
edit: forgot to say what actually works for me. i tried the sunday tune rebound and still found it not fast enough for my liking. i just ended up putting all the small shims under the big ones, its fast now. yet to test it enough to say whether i am happy with it.
Not 100% sure how many smaller discs you put between the big ones and the piston, but if it's three or more your rebound is probably quicker because the big discs aren't seating against the piston! I measured the piston preload to be 0.25mm and the smaller discs to be 0.1mm thick. Three of the smaller discs would mean that there is a 0.05mm gap between the outer piston land and the larger discs.

Re. HSR, from what I've seen with other dampers, it's a function of the disc stack configuration as well as the piston orifice area. So to decrease it, you could thin off the disc stack, or open up the orifice area (drill holes!) or do both. That said, I'm not really sure if mtb dampers really see the sorts of piston speeds that are really affected by orifice area (lots of leverage = lower piston speeds)

My piston stack with two discs sounds pretty light as is, so if I decide that I want to speed up LSR, I think a bleed disc on the piston would do the trick. This would allow oil flow at lower speeds to go through the bleed slots. At some point, the oil flow would increase enough to cause the bleed disc to spike and then blow off the rest of the stack like normal (although it would be a little stiffer with the additional of the bleed disc.) So my stack would look like this:
Piston
Small disc
Bleed disc
Two big discs
Two small discs

(I attached a pic of a bleed disc if you're not sure what it is. Bleed area is a function of the disc thickness and slot width, multiplied by the number of slots)

My control valve is cylindrical shaped btw, and I have an allen bolt on the piston bolt head stack (which i couldn't undo - I'm wondering if it's reverse threaded?)
 

Attachments

dhkid

Turbo Monkey
Mar 10, 2005
3,358
0
Malaysia
i checked before i put everything back together and it was sealing. so must have been two small shims then.

i have heard of people drilling out the pistons, but i haven't gone down that route yet because there is no turning back.

be careful when you reduce the number of big shims, you might not have enough HSR and get bucked when the shox goes deep into its travel.

the allen bolt on the top of the piston bolt is imperial size, so is the bleed screw near the beginning stroke compression adjuster. if you dont have excess to imperial allen keys, you can always use a lock jaw plier to unscrew it, you dont need much force to open it.
 

-Danno-

Chimp
Jan 31, 2006
39
0
the stock oil used in it is torco 10wt. i just use silkone 10wt, but my shox uses 7.5 wt for faster rebound purposes. i think the ifp depth on a 2.75x8.75 shox is 34mm. sorry, i dont know them, i always measure the end cap maximum length then add a few mm for the ifp depth at bottom out.

i remember someone posting the info in this thread. its a long read.
http://www.ridemonkey.com/forums/showthread.php?t=163201&highlight=dhx
Thanks, that was very easy. I measured the extended IFP depth at 28.5mm before I pulled it apart. The volume ratio is 4.55 so based on your depth for the 2.75 mine should be 29.5mm. So there's a 1mm error there for some reason.

The old oil was really dirty. Because the shaft is alloy I didn't want to risk pulling the eyelet to clean the seals. I replaced the oil with Golden Spectro Very Light SSF (26 cSt @ 40c) high VI.
 

-Danno-

Chimp
Jan 31, 2006
39
0
what i am trying to explain to you is that you dont have to think of it as in LSR shim stack and HSR shim stack.

think of it this way, if you took all the shims out. whats left is two holes (of course the HSR circuit has more holes but just call it one big hole), the proper name for it would be orifice. now the LSR circuit has a much smaller orifice then the then HSR circuit. at the volume of oil moving through each increases, the lsr circuit will reach a maximum volume flow rate and spike much earlier then the HSR circuit. thats what they are called LSR and HSR circuits, becuase the LSR circuit can only handle the smaller volume flow rates (low shaft speeds) but the HSR circuit can handle much higher flow rates and thus speeds.

BUT, this doesn't mean that the HSR circuit cannot handle the low volume flow rates. you can think of shims as something that is controlling the size of orifices, the more force you put on them, the bigger the orifice becomes. so in theory, the size of the orifice will vary from fully closed (metering low volume flow rates) to a fully open one, and what controls them is the shims.

you can close off the LSR circuit and reshim the HSR circuit to your needs. the reason the LSR circuit is there is because it is a way so that rebound can be adjusted externally. and this shims are there mainly to act as a one way valve, so that your rebound setting doesn't effect your compression setting.

you should do some reading on how shims work.

i hope that makes sense.


as for having different shims, it sure does wound like it. your control valve, does is it cylindrical shape or bowl shaped? if its cylindrical shape that means its the older model, different from what i have.
Thanks for the insight, it does make sense. I generally understand the concepts behind different types of shim stacks and valve orfice shapes, but I've no clue how to compute force-velocity numbers for them. It would be cool to have a software calculator. ;)

If I really wanted to change the shape of the shim stacks I'd have to find some. Right now the only 8mm ID HSR shims I've got are all the same thickness and OD. I did a little test ride on that configuration I posted above and it really feels good, but I haven't hit any extreme bumpy high speed stuff or a drop that would cause me to really blow though travel.

I found 3 of my shocks have the old style CV, 2 are the newer type. I believe they may all have four 8mm X 18mm X 0.13mm shims stacked on the main piston, I'm not sure about the LSR shims, but the two that I've pulled apart were different and they both had the C-clip retainer.
 

dhkid

Turbo Monkey
Mar 10, 2005
3,358
0
Malaysia
you can clean the seal easy just take the main piston off the shaft. its held on by a small bolt. once that is off you can then slide the the cap/seals/bushing thingy off the shaft. you can then take the main seal (which is an o ring) out with a pick. in my experience you dont get dirt trapped there, the oil is dirty because it has broken down or just internal contaminants.
 

-Danno-

Chimp
Jan 31, 2006
39
0
Also, with your Bullit you could wind the volume adjuster in a bit to help with the falling rate and if you could go in on the Beginning Stroke Adjuster too to help while jumping.
It looks like three turns would help quite a bit with bottom out, and not affect the rest of the stroke a whole lot.

Based on my measurements:



BTW, I noticed that there are 6mm and 8mm I.D. shims available on the "SHOP FOR PARTS" link off www.suspensionnetwork.com. $1 each. For those wanting to shim the compression side there are some 24mm X 8mm that would probably work in place of the CV (which is ~25mm). 24mm's would expose a little more of the rebound inlet.
 

-Danno-

Chimp
Jan 31, 2006
39
0
A friend finally trashed his 5th on his 2005 7point. I got ahold of it to take apart and see how it was shimmed compared to the VPFree/V10 shocks. Here are the results:

LSR - VPFree

Valve
Shim 6 X 10 X 0.1
Shim 6 X 15 X 0.1
Spacer


LSR - 7point

Valve
Shim 6 X 10 X 0.1
Shim 6 X 15 X 0.1
Spacer

So LSR is the same for both...


HSR - VPFree

Valve
Shim 8 X 18 X 0.1
Shim 8 X 18 X 0.1
Shim 8 X 18 X 0.1
Shim 8 X 18 X 0.1
Shim 8 X 12 X 0.1
Shim 8 X 12 X 0.1
Spacer


HSR - 7point

Valve
Shim 8 X 12 X 0.1
Shim 8 X 18 X 0.1
Shim 8 X 12 X 0.25
Shim 8 X 12 X 0.25
Spacer

Significant difference for HSR. The 7point HSR damping appears to be much lighter for lower shaft velocities. That 12mm X 0.1mm shim seems to remove enough preload off the 18mm to overlap the LSR adjustment. The single 18mm shim will open earlier, but it is backed by the two thick 12mm which will limit the high end velocity.


I can't imagine there's any difference in the compression damping between the two shocks given the same pressure and vol adjust. The rebound and compression shims on the valve at the reservoir base were both 0.1mm thick for the 7point, I didn't check it for the VPFree shock yet.
 

MttyTee

Monkey
Jun 20, 2007
209
0
Back on the east coast!
Another little trick is to add another 6 x 10 x .1 under the LSR stack for low levered bikes. Gives a little better traction over the stuttery stuff. Also, a pyramid stack on the HSR is a nice touch. Same 8 x12 x .1 under it.
 

Sov

Chimp
Jan 1, 2008
73
19
Adelaide, Australia
I ended up with the following on the rebound side of the piston:
12x0.1
18x0.15
12x0.1
18x0.15
16x0.15
14x0.15
12.7x0.15
Spacer

Didn't touch the piston bolt stack.

Feels good - nice bit of pop off jumps now and feels better matched to the front end. I think the staged stack is a good thing as the first disc cracks easily for less LSR and then firms up for mid/high speed control. This is on a Heckler btw. I picked up a VP-Free frame off ebay last week so I'll soon have another shock to play with. Will probably start out with an oil change and a 70 duro seal. I'm also planning to reduce the stroke by 0.25" - hopefully the hydraulic top out still works ok with a small spacer in there.
 

-Danno-

Chimp
Jan 31, 2006
39
0
Another little trick is to add another 6 x 10 x .1 under the LSR stack for low levered bikes. Gives a little better traction over the stuttery stuff. Also, a pyramid stack on the HSR is a nice touch. Same 8 x12 x .1 under it.
Based on one of your earlier posts I made that mod to the two 5th I'm currently using and it does help a lot. Because of my shim selection I actually put a single 8 X 12 X .25 under one of them. I was a little worried that it might be deeper than the dish, but it seems to be working fine.

Any pyramid ideas for a 2.6 something LR Bullit? My higher ratio DH bike is working pretty nicely with three 18 X .1 followed by some 12's. I have to order a better 8mm ID shim selection one of these days.
 

-Danno-

Chimp
Jan 31, 2006
39
0
I ended up with the following on the rebound side of the piston:
12x0.1
18x0.15
12x0.1
18x0.15
16x0.15
14x0.15
12.7x0.15
Spacer

Didn't touch the piston bolt stack.

Feels good - nice bit of pop off jumps now and feels better matched to the front end. I think the staged stack is a good thing as the first disc cracks easily for less LSR and then firms up for mid/high speed control. This is on a Heckler btw. I picked up a VP-Free frame off ebay last week so I'll soon have another shock to play with. Will probably start out with an oil change and a 70 duro seal. I'm also planning to reduce the stroke by 0.25" - hopefully the hydraulic top out still works ok with a small spacer in there.
I'll have to try a two stage like that too. I'd probably go even lighter because your Heckler has a higher LR.

You probably just have to make sure the spacer doesn't slide down the shaft and block the LSR port. It seems like the topout would work perfectly if that spacer was pretty tight on the shaft and could somehow be held against the seal head.
 

MttyTee

Monkey
Jun 20, 2007
209
0
Back on the east coast!
Any pyramid ideas for a 2.6 something LR Bullit?
I'm currently using this tune on a Sunday.
Piston Bolt
15 010 01
12 010 02

Main Piston
12 010 02
14 010 01
16 010 01
18 010 01
12 010 01

Using a .25mm shim to "un"preload the stack is fine. It is a .25mm dish piston so it takes all the preload off the shims. Something to keep in mind though since you need a beefier stack to compensate, the total stack of shims should be .6mm to keep the bolt in the proper spot relative to the rebound needle. Post style shafts are so much easier to tune with, but bolt style shafts are much cheaper to manufacture, damn bean counters

Also, regarding multi stage stacks...more is not always better but it is always more complex
 

-Danno-

Chimp
Jan 31, 2006
39
0
Thanks for the stack info MttyTee, and good point about the rebound needle. I overlooked that.
 

-Danno-

Chimp
Jan 31, 2006
39
0
MttyTee, have you modified the compression shim stack on the valve at the base of the reservoir at all?

The high speed compression path between the chambers handles both compression and rebound right? It probably has a fairly big bore allowing a lot of oil movement? The shimed valve is in this path.

The low speed path only allows oil to move into the reservoir due to the check valve at the end of the needle? It must have a pretty small bore that tops out at low shaft velocities?

Is tough to see what's going on in that part of the shock.
 

MttyTee

Monkey
Jun 20, 2007
209
0
Back on the east coast!
Check page #1 of this post for cutaway pics. Both bores are the same size but the way the oil is metered at the ends are different. As you turn the LSC adjuster in it preloads the small spring and also reduces how far the little piston can check open, and I'm sure you're well aware of how a needle works. Keep in mind though that "high" shaft speeds on rebound are much, much lower than "high" shaft speeds on compression.

I am currently running a significantly beefier stack on the compression piston but the results are barely noticeable. I want to say it has added a small amount of through stroke damping or mid speed but that could be a placebo effect. I think the HSC adjuster meters the majority of the oil.

I wish I had a dyno available to verify.
 

-Danno-

Chimp
Jan 31, 2006
39
0
OK, got ya. The LSC metering point really is just at the check valve.

These tweaks have really made my shocks a lot nicer. Because of ride feel I'm actually back riding my Bullit w/5th a lot more than my Turner 6-Pack w/DHX.
 

tonyl

Chimp
Oct 2, 2007
16
0
So, trying to not hijack this thread for a total newbie on shock stuff but
2 questions.

I have a "extra" 5th 8.5x2.5 from my 04 bullit (bought a new one from SC when they blew them out) an the new one on my bullit.
I just picked up a Azonic eliminator frame with no shock and I put the 5th on it. Seems OK nothing hitting.

So, Is there anything else I ned to do? The reason I'm asking is i found a 9x3 5th for next to nothing that the person says was on a IR sunday(that was tuned for it) and states that if you are going to put it on anything else you need to rebuild it.

Is that true? I would like to use the longer stroke for the azonic but don't really understand why it wold need to be rebuilt.
 

-Danno-

Chimp
Jan 31, 2006
39
0
What shock length is spec'd for the Eliminator?

I would think the Sunday tuned shock will probably work better than a standard tune. It'll have lighter rebound damping, which is what most of us are trying to achieve by modifying them.
 

tonyl

Chimp
Oct 2, 2007
16
0
They crazy thing is almost anything 8.5x2.5 or 9x3.. The eliminator and Recoil (m-1 style design) have a million adjustment settings. I can move the pivot point all over the place. Up and down and the main pivot (has 3 height adjsutments) and then the rear of the swingarm linkage also has 3 differnt placements.

it's overkill but I know the 9x3 will fit and give me the full travel. 8.5

I'm not sure but the way I have it I think I'm around 7.5 ( not that that's not enough!) but It's a killer deal of the 9 x 3...

Thanks
 

kebarb

Chimp
Apr 8, 2007
58
4
It's a reverse thread so more ProPedal reduces preload on the spring allowing the Boost Valve to close sooner/ farther.

I've tried different weight oils but haven't found any benefits. That being said there is a difference between different manufactuers 5wt. I use Showa 5wt which has similar properties to the stock stuff. Someday I would like to do a full run test on a bunch of different oils of the same weight

I'm curious to see what you think, too!!

I didnt finish reading the thread yet, but there is a website by Peter Verdone where wh has some measuring of cSt of alots of different oils, maybe you havent seen it yet and would find it intreresting?

URL:
http://www.peterverdonedesigns.com/images/content/motorcycle/PVD-ISO-Viscosity-Data.gif

//K
 

dhkid

Turbo Monkey
Mar 10, 2005
3,358
0
Malaysia
hey mtty tee, more questions for you.

i am kinda baffled at why the bsc and esc circuits are designed the way they are. i dont quite see the point of it all. since the esc adjuster only works by controlling the upper limit of the high speed compression (since its a port damper?). ideally dont you want to control the whole range and not just the upper limit? every other example of a hsc circuit i see isn't a port damper.

further more, that shim on the valve thats in the piggy back, that forces the oil to flow through the bsc (lsc) lsc circuit first right? before that created enough force to deflect the shim and the allowing oil to flow through the esc (hsc) circuit?

the whole thing is kinda weird since i am lead to believe that you want hsc to reduce with speed. a port damper would make it increase by ^2, wouldn't that cause a hell of a lot of spiking? hence making the hsc adjuster useless for any practical adjustments?
 

MttyTee

Monkey
Jun 20, 2007
209
0
Back on the east coast!
Well, I can't comment on the design process that Progressive went through, I wasn't there, but I can certainly give my opinions...isn't that what the internet is for.

In theory you're spot on, in practicality it's never as simple as it seems. If the ESC adjuster were the only source of damping it would be a wallow monster and spike like a mother, but there are other sources of damping so the ESC adjuster is just adding to the already present damping sources (which like the ESC are changing with shaft velocity and/ or position, making the end of the equation harder than Chinese Algebra).

So, yeah, ESC is a port damper, but the port size is adjustable with a needle. There is a shim, but in my experience it is more of a check than a major source of damping. Also, as you stated, the shim forces oil through the BSC circuit first, which uses a spring loaded "poppet" valve and then bleeds through the center of the valve.

IMO (and properly set up) the control valve is extremely affective at taking the edge off sharp, spiky hits and provides position sensitivity so it can handle bottoming loads. Where it lacks is mid stroke. Looking at an average damping curve it looks like an air spring curve and gets flat(or flatter) in the middle. I always used the ESC adjuster as a helper to control large amplitude through stroke damping. It seems like on high shaft velocity, large displacement hits the CV blows open then hangs open for a slight moment, not slowing the shaft down, then can't quite catch up at the end with the bottom control (one result is the user adding air pressure to prevent bottoming which makes it harsh initially). I've found with the addition of some ESC it helps slow the shaft down just enough to let the CV do it's job effectively.

On a side note one of he things you get when you step up from production moto dampers to A-kit or Factory is a jet bleed that sits behind the compression adjuster, so the oil goes from the main body through the bleed, through the CA, then into the resy. Again, by itself pretty stupid and useless but as a small addition to existing damping, it helps out.
 

-Danno-

Chimp
Jan 31, 2006
39
0
MttyTee, I've been running modified 5ths on two bikes for quite a while now and I'm really happy with their performance. They've got the lower duro o-ring, reduction of LSR and HSR shim stacks, as well as more HSC than I was previously running. All changes you recommended. Good stuff.

:beerjam:
 

Cabdoctor

Monkey
Mar 25, 2008
193
0
Sacramento
I need some shim advice. I have an 04 big hit. 8.1" of travel 8.75 x 2.75 shock with a 1 to 2.94 leverage ratio that's a falling rate. According to Linkage, it starts at 3.7 ratio and ends at 2.6 with a pretty linear curve. I was going to order some shims for both rebound and compression. Could someone recommend what I should put on there? I weigh 130lbs without gear(haven't weighted myself with gear) and I'm going to be racing this machine during the summer.
 

davep

Turbo Monkey
Jan 7, 2005
3,276
0
seattle
Cant help you with the shims (although IIRC Mttytee provided much of that kind of info in a few threads (this one))...

but that is a rising rate (I know it sounds backwards). As the shock compresses, it moves from ~3:1 toward 1:1...the shock shaft moves more for each increment of the rear wheel....
 

dsb18292

Chimp
Mar 24, 2009
68
0
Excellent thread. Thanks for the info. Internal, FarkinRyan,and DHkid, what was the outcome on your shocks? Still happy? Still tinkering? Moved on?

edit, oh crud there is still a few more pages to read...
 

dsb18292

Chimp
Mar 24, 2009
68
0
Got one question for the gurus...

Does the rebound knob/port control high and low speed rebound or just the flow to one of the shim stacks??
 

dhkid

Turbo Monkey
Mar 10, 2005
3,358
0
Malaysia
the rebound needle only controls the LSR flow, which passes through the smaller shim stack. HSR is purely through the HSR shim stack.

unfortunately my tinkering days have been put on hold, i am at my 3rd year in uni now and barely have enough time to ride my bike. i still have the shock at home half way round the world, but i dont use it anymore as the bike it fits on is cracked and doesn't fit the little bike i have now.
 

dsb18292

Chimp
Mar 24, 2009
68
0
Cool, thanks for the reply. Looking at the pictures I have found that looked like what was going on. I also noticed even when closed down that the high speed rebound was moving too fast. It is almost like they never expected someone to run a 550lb spring on it :)

I am just figuring out if I needed to re-shim the HSR stack while I am in the shock. Sounds like yes.
 

jrlandry

Chimp
Sep 9, 2009
1
0
I know this is an old thread, but does anyone have a listing of the generic o-ring sizes to rebuild the 5th Element? Most importantly, I'm looking for the ones that fit on the main cylinder cap.