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Discussion Starter #1
I plan on working on my forks this winter since they have not been touched since Ive owned the bike (3 years or so with low mileage last year) and was wondering if revalving them is worth the cost. Im limited on my budget and will replace the springs at least but since I dont do a lot of spirited riding is getting the gold valves worth the cost and effort to get? Thanks.
 

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If you have adjustments for compression and rebound I would say no. If you don't then maybe be worth it but you have to get it right.
You could also go either lighter or heavier weight on your oil depending on which way you want to go.
On the other hand, improvements equals added enjoyment and in some cases safety.

Paul 03 ST4s, 15 675RX, 96 ZX11, 76 KZ900LTD B-1, 72 SL125
 

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Discussion Starter #3
Yeah I have the adjustments on the forks (Showa I think) so maybe I'll skip the valving. Fortunately they are not leaking but I'll replace the seals anyway along with my steering bearings since I'll have it apart. The only issue I really notice is the dive when hitting the brakes. I have reduced rider weight with more to go hopefully but I think I still need stiffer front springs.
 

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Yes, those earlier Showas are very adjustable, and can actually be a pretty nice fork - especially since you already paid for them! You could start by adjusting/increasing the preload - that's the large "nut" in the center of each leg. You could also try adjusting the compression damping clickers at the bottom of each leg. Failing that you could change the fork oil with a known weight and quantity, say a good quality 7.5 or 10w ( Motul Factory Line or similar) to start with and see how that feels. I find mine quite sensitive to change and definately notice a click or 2 either way.
 

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The gold valves are a very good improvement and well worth the cost and effort if you take the time to set them up. Keep in mind the adjustments you can make outside the forks are for low speed compression and rebound only. Where the gold valves make a nice improvement is in high speed compression (sharp sudden bumps that can jar you). The gold valve and shim stack you add are for exactly that, high speed compression. The only way you can mess with that adjustment without re valving is to change oil weight, but it doesn't come close and it changes your range of adjustment on low speed comp and rebound as well.

It is also important to note that the non-Superbike Showas of the time are flawed in that the compression and rebound circuits are not independent. Unless you have the rebound screw closed (and you most definitely should not) the compression adjustment doesn't do very much as fork oil will back flow through the rebound circuit when the forks compress, essentially short-circuiting it in electrical terms. It has some effect, but not much.

I have gold valves on my ST and they are very nice. Bike is smooth, compliant over bumps and well controlled. Recommended.

That being said, just adding fresh oil and servicing the forks will make a nice improvement. The oil you use can really make or break the job. I always go with 5W Bel Ray fork oil (not the suspension fluid, their is a difference). Why specify the brand??? Glad you asked! Fork oil and suspension fluid will give you much stress. From brand to brand you cannot shop by advertised oil weight and get the same result. You are shopping for real viscosity index measured in centiStokes. BTW, Suspension fluid is different in that it maintains its viscosity index better at high temps and is meant for shocks, not forks. It's also more expensive.

This chart is sorted by centiStokes at 40C. The Bel Ray I like is in the 17.00 range and works for me.
Fork oil weights

If you have original oil, it is likely Showa 8wt (I think that is what is listed in the manual). I've never come across and 8wt fluid. You'd need to mix their 5 and 10wt.
 

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I'll echo what SS904 said. A revised compression stack will make a noticeable difference (performance and ride) regardless of whether comp/rebound is adjustable or not. If you're opening the forks up for servicing, do yourself a favor and spend an extra $120.00 to install a Race Tech comp kit. It's the cheapest and most effective performance upgrade you can make, more so if you have to have the forks apart for servicing.

Scott L.
 

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Look at the roads you ride, in New England our roads are rough with lots of bumps. High speed damping is important here due to the bumps , keep in mind we are talking shaft speed NOT bike speed. So if you have a lot of bumps that push the bike back at you rapidly that is a high speed bump, If your roads are smoother and have few bumps I do not think I would spend the money. My track 750ss forks are NOT valved because most tracks are smooth and there are downsides to too soft a high speed compression stack.

Springs that are selected for your weight will get you the largest benefit and after that it will be down to your riding area and what your preferences are. Keep in mind there are almost always compromises to be made so be realistic in what you are trying to do.

As to the "flawed" design of the fork I disagree, it is no different than the majority of Ohlins shocks out there. There are a couple of years where there is a defect in the showas around 2001 where yes the damping adjusters bleed too much off making the adjusters pretty ineffective. That said it is the same internals since 92 851 right up until the late 2000's and I have valved/set up the vast majority where the adjusters work normally. I would expect a 98 showa to be fine.

Again I would start by looking at your roads and if possible talk to some suspension shops near where you ride to get feedback from others in your area. Taking advice from people who are riding on different conditions may not give you the results you desire. I can not tell you how many valved forks we have had to fix because they were done by someone with no idea what our riding conditions are. The parts are good but remember you are picking a stack that is essentially programming the high speed damping, these can be changed but will require disassembly again.
 

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I have a 2002 ST2. This was the last year before Ducati stopped the ST2 and as such they cheaped out on components. My forks were completely nonadjustable. After reading on several different forums, I decided to go with GSXR600/750 internals in the stock Ducati ( Showa ) housings. LOTS of work! Hours on the mill and lathe and NO I`m not going to do that again!

Was it worth it? Wow! What a difference! Different bike. Still needs some tweaking but much, much better over bumps.

Got the forks for about $200 plus my time which works out to ohh, not very much per hour.
 
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As to the "flawed" design of the fork I disagree, it is no different than the majority of Ohlins shocks out there. There are a couple of years where there is a defect in the showas around 2001 where yes the damping adjusters bleed too much off making the adjusters pretty ineffective. That said it is the same internals since 92 851 right up until the late 2000's and I have valved/set up the vast majority where the adjusters work normally. I would expect a 98 showa to be fine.
Well you've got a lot more experience on different model Ducs than I have, but I can tell you unequivocally that the Showa forks in my '97 SS/SP were flawed, and exactly for the reasons stated above. Any adjustment to the rebound damping also affected the compression damping which made it REALLY challenging to get it set up right. There's been lots written on this issue, and how to fix it, but believe me it definitely exists and is a design defect... I don't know how many bikes these forks are on but all the SS/SP's had them through '97 (probably FE in '98 also).
 

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Discussion Starter #10 (Edited)
Most of the roads I have been on so far have been fairly smooth. The only notable exception is one road headed to Laramie WY but its only on the straight parts that get rough. If I have the money I may just do the gold valves because why not? BTW can the stock rear shock be upgraded? Boulder Motorsports pretty much said just run it until it goes bad then upgrade to a different shock. Also, I really appreciate the feedback on this. Im going to be rebuilding them myself since the dealer wants $400 and its something that I need to learn anyway. Worse comes to worse I bring them the disassembled forks.
 

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Easy work. This link is a very good how to. Not my work, it's been around for a few years. These are Monster S4 forks, but the SS, ST and Monster adjustable Showa of the time are the same.

https://www.waste.org/~knobs/fork_rebuild1.html
 

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If the cost is not a factor then adding a better valve design is not a bad idea, you just may not notice it much. again the springs properly set will gain you the most.

dspear99ca

I am not saying the circuits do not overlap because they and many others do. What I am saying is that most will be more than enough functional for the majority of riders without a issue. There will be outliers of course who either need or simply want either the added range or theoretical range that other design systems have. There are options for everyone and it is up to the rider to know what their demands will be.

Having circuits overlap is not uncommon at all, most manufacturers have alternative systems that do not. These are saved for higher end suspension for those wanting to spend a bit more to get a more precise system, the manufacturers do NOT discontinue the old designs usually they simply market them differently. The poor compression valve and damper design used on supersports were used for well over a decade on multiple models in the ducati range as well as on other brands like GSXR's in the early years and some Honda models as well.

There can be improvements to the design, the question becomes does it need to be changed for your average rider. In my experience not often, in fact most suspension will never be re-adjusted after it is set up the first time unless there is a rider change or large weight gain/loss. Racing is another animal entirely and when you run multiple tracks under the stop watch you do make changes and need to be precise if the rider can benefit from it. I have worked with some who needed frequent oil changes to stay consistent and other expert racers who made no change with massive swings. I just rode a 996 on the track two days ago that was the most foul handling bike I have ridden in many years, was it components or design? Likely not just a setup issue .
 

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I fairness, since doing the gold valves on the ST and getting things set as I want, I literally haven't touched them other than to open them up again for seals and fresh oil. No need to.

That being said, it is much more than some overlap between circuits on the non-Superbike adjustable Showas of the time (ST, SS, Monster).

The Superbike fork cartridges have a rebound adjuster at the top that is a long rod running down the hollow shaft of the cartridge to a proper rebound valve in the cartridge body. When the cartridge is in compression, most of the oil is forced through the compression adjuster valve at the fork bottom. The long rebound rod fills the hollow shaft keeping most of the oil where it belongs during compression.

The cartridges that come on the other bikes also have a rebound adjuster at the top of the fork, but there is no long rod leading to a proper rebound valve in the cartridge body. The rebound valve sits at the very top of the hollow shaft. With no long rod filling the hollow shaft, when the cartridge compresses, the oil takes the path of least resistance and pushes right up the hollow shaft and through the open rebound valve. Pretty much rendering the compression circuit ineffective. The only way to truly make the compression circuit effective is to close or mostly close the rebound valve preventing the oil from pushing up that shaft which would force it through the compression valve. Which of course is a very bad idea unless you like your forks to pack up on you!!!

This is certainly a design limitation, if not a flaw. They can be adjusted to suit, but thinking you have a separate low speed compression and rebound adjustment on a non-Superbike fork is a bit of a reach in practice. The Superbike forks are much better in that regard. Needed for the street? Probably not, but it's there.
 
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