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Discussion Starter #1 (Edited)
Preface
This is my DIY guide on changing springs on the Ohlins forks of the SSS, as well as changing the oil without disassembling the forks.

There are some discussions on the forks, but no real instructions on how to change the springs. I watched some videos on YouTube and looked at the Ohlins shop manual, which they provide on their website. Much of the specific info (part numbers, etc) I've shamelessly stolen from other forum contributors posts. Thanks!

The guide itself won't be the most beautifully laid out and, to be honest, I didn't take pictures of every step because I didn't think about doing a guide until I was already started.

You can look at post #12 of this thread for an alternate method of changing just the springs.

Disclaimer

This is also not an absolute step-by-step guide. If you're not mechanically inclined, or have many basic tools, enough to remove fasteners, wheels, brake calipers, etc, without step-by-step then I would suggest having a shop, or a friend, do the work.



Technical Specifications
SSS Fork#: FL9370 (This is a manufacturer specific part number), but it's a modified FGRT fork.
Stock springs = > ref. Öhlins 04744-80 8.0N/mm (hardness 800 gr)
Oil = > ref. Öhlins 1309-01 (viscosity 19 cSt in 40°C)
Level of oil = > 150 mm of space of air

If you have any specific questions, you can reach Ohlins USA via (828) 692-4525‬ Ext 313. Ask for Jerry.

New spring = > 04744-90 9.0N/mm Note: You can use different rated springs in each fork leg. This is specifically called out in the fork shop manual!

I'm using Motul Factory Line fork oil One 1L bottle is all you should need. I ordered 10W, thinking the Ohlins stock was 7.5W. Turns out the weight number doesn't mean ****. Check the actual viscosity rating in manufacturer documentation. The bottle doesn't list it, so you may have to dig if using a different brand. Motul 10W has a viscosity index just under double the factory Ohlins stuff. Oops. I'll add more thoughts if this is just way too thick for my weight.

You can use this chart from Motul to see the viscosity ratings to decide what will work for you best if you want a similar, or thicker, oil than stock:
https://d23zpyj32c5wn3.cloudfront.n...Fork_Oil_Factory_Line__28GB_29.pdf?1492016021

Useful Links
FGRT Ohlins shop manual: https://www.ohlins.com/app/uploads/world/2012/03/OM_07282-07_2.pdf

Dave Moss "Dump & Run" fork oil exchange:

Extremely long video on complete tear down and rebuild of a similar Ohlins FG42 fork:

SuperSport Torque Values (Thanks to @mot937): Torque Settings - Supersport.PDF

Specific Tools
-Fork cap wrench for Ohlins (Or fancier fork cap socket)
-Snap ring pliers
-Torque wrench
-Oil measuring cup
-2x bungee cords
-Headlift stand (If you don't have one, or some DIY method to lift the front of the bike, just pony up and buy a pitbull stand w/ #42 pin; way better than the cheap one I got that doesn't work)
-Calipers
-Needle nose vise grips
-Needle nose pliers

If you only want to change the springs, you do not need to remove the forks from the bike!

Fork leg height
Before loosening any triple clamp bolts, use the calipers to measure the height of the forks. Refer to my second post for an image of this.

Guide

1. Remove the plastic cover that screws into the lower triple tree to gain access to the steering stem hole. Lift the front of the bike using a stand. It is also recommended to have the rear up on a stand for stability. (Or other DIY method, i.e. ratchet straps on the upper triple to overhead rafters)

2. Remove the axle nut on the left side of the bike.

3. Loosen the pinch bolts at the bottom of the fork.

4. Loosen the brake caliper bolts.

5. Unscrew the plastic ABS cable routing cover, two bolts. And the ABS sensor. Remove the brake caliper bolts and remove the brake calipers. Clean the anti-seize off the bolts.

6. Support the front tire while pushing the axle out to the right. Remove the axle and clean it off. Put the wheel somewhere it won't fall over onto the brake discs.

7. Remove the black plastic shrouds on the upper fairing that are next to the forks. There are three screws in each one.

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8. Secure the calipers with bungee cords to keep tension off of the brake lines. You don't want to let the calipers hang by the brake lines. (My bungee cords have plastic hooks, so I hooked them to the fairing.
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If you're only changing the springs, you can leave the ABS stuff in place. The following steps are laid out as working on one fork leg at a time!

9. Loosen the bolts that hold the clipons to the upper triple tree. You will have to loosen the brake reservoir armature and the clutch lever to get to the bolts.

10. Use some soft material to protect the fairings and let the clipons hang on the fairings. There are enough wires that I'm not worried of putting too much tension on them and causing damage. I wrapped a paper towel around the reservoir just in case it leaked.
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11. Loosen the upper triple clamp bolt. This is important because no doing so will make loosening the fork cap much harder than it needs to be and potentially cause damage to the fork cap holes.

12. Using a 17mm socket, completely back off all preload tension from the fork leg!!! Use a paper towel or plastic to prevent marring the blue finish. (I didn't do this at first, so one of my preload adjusters is all ugly now. =[)
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13. Using a properly sized pin wrench (or socket), loosen the fork cap top. Eventually, you will be able to spin it off by hand.
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14. Spin the fork cap all the way off.

15. At this point you will need some way to support the bottom of the fork. You will need to fully compress the fork and keep it held that way. This will expose the assembly and make it easier to take apart. My method is pictured, but it was not robust and I had to add another block of wood...
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16. Say hello to your fork cap and fork spring! I'm sure the spring is happy to be replaced and quit being abused by your weight. Clean up the fork cap threads and the corresponding threads inside the stanchion. In the picture you'll see the lock nut you need to loosen to get the fork cap off.
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17. My method isn't beautiful (ohlins employees shield your eyes) but it work. Using a pair of snap ring pliers, pry the metal spring seat apart from the fork cap and slip a 17mm wrench in onto the nut. You may have to wiggle the spring seat to get it to slide down the shaft. All metal parts of the suspension are ALUMINUM! They will marr, scratch and dent VERY easily. You won't see it in this picture, but I wrapped painters tape around the ends of my snap ring pliers after putting marks on the parts. If you do cause damage, use some 400grit sandpaper to lightly sand down any sharp edges that may catch on anything. The assembly will try to twist on you, so be cautious that it doesn't spin and snap closed on your pliers, which will damage the aluminum bits. (Ask me how I know)
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18. Holding the fork cap tight, loosen the jam nut with the wrench. You can hold tension on the spring with the snap ring pliers and remove the wrench. Slowly release tension.
 

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Discussion Starter #2 (Edited)
19. Spin the jam nut down against the spring seat. Use those needle nose vise grips (Wrap the jaws in tape to keep the knurling from marking the shaft) to hold onto the center shaft between spring coils with only enough pressure as necessary to twist the fork cap off using the fork cap wrench. The torque is not high, but be cautious you don't throw your wrench into the fuel tank.

If the vise grips on the shaft isn't working, you can use the 17mm wrench to hold the jam nut once it has been spun down far enough on the shaft to tighten.
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20. Spin off the fork cap. Wipe it clean and set it aside. (If you're curious, the inner cylinder is what goes down when you increase preload, pressing against the spring seat and compressing the spring)

21. The shaft will drop down into the fork. This is fine. You can use those needle nose pliers I mention to pull it back up when you need to. There is a special tool that you can find online that screws onto this shaft so you can pull it up, but I'm not spending $30 on that.
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22. For whatever reason, my stock springs have no labeling on them to signify what spring rate they are. Just some ground in dashed lines. New vs. Old.

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23. Pull out the old spring, be sure to let as much oil as possible drip off of it back into the fork.

24. Insert the new spring with the lettering facing up, but don't drop it because oil may splash up out of the fork.

25. Using those needle nosed pliers, light grab the shaft and pull it back up.

Things get a little tricky from here

26. Use your taped up needle nose vise grips to hold the shaft between the spring coils like before.

27. Reinstall the spring seat, making sure it's correctly oriented. You may have to wiggle it to get it seated properly onto the spring. It should be sitting flat on the top of the spring.

28. Spin the jam nut on as far as you can by hand. You should have just enough threads to get the nut started without having to compress the spring. But if you don't, use the needle nose to hold the rod while pressing down with the vise grips to compress the spring, then clamp them down once you have enough threads showing to start the nut. There is a spot with no threads you can grip on the shaft. I did no damage to my threads!
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29. Using a 17mm deep socket start to tighten the jam nut down to compress the spring. As you do this you will need to release and regrip the vise grips to relieve tension on the coils that are squeezing against the grips. Tighten the nut all the way down. Then back it off about one turn. If you leave it tight against the last thread, it will be a PITA to loosen it with the top cap on.

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30. Spread a very small amount of bearing grease (usually the red type) on the sliding surface of the spring cap. This is where the inner cylinder of the fork cap spins against it to compress the spring for preload. Nobody likes unnecessary friction! (This probably isn't necessary, I'm sure it gets fork oil on it eventually, but a very small amount of grease should have no detrimental effect on the fork oil)

31. Spin the fork cap back on, being careful not to cross thread it, as far down as it will go. Hold the shaft with the vise grips and use the fork cap wrench to tighten down the fork cap. Something like 15-20Nm. (Check the shop manual)

32. Spin the jam nut up until it's against the bottom of the fork cap. Using the same method used to take it apart, pry the spring seat down, insert the wrench, grip the shaft with the vise grips, and tighten the jam nut. Something like 15-20Nm. (Check the shop manual)

33. If you hold the fork cap with your hand, you can test the preload adjust still works by turning it with your 17mm socket. You'll slowly see the inner cylinder of the fork cap extending down, compressing the spring. Back the preload back off.

34. Remove whatever you're using to hold the fork out and gently lower the fork leg until it is extended.

35. Spin the fork cap counter-clockwise until you hear a click, this is the first thread dropping. Doing this will make it easier to engage the threads and to ensure you don't cross thread your expensive suspension components. Make sure the rubber o-ring has a little bit of fork oil on it for a proper seal and to let it slide easily back into the fork. Now you can spin clockwise to tighten the fork cap by hand.

If you're going to remove your forks to change the oil, skip to 39
36. Using the fork cap wrench, tighten the fork cap down. 20Nm, I think. (Check shop manual for torque)

37. Tighten the upper triple clamp bolt that you previously loosed. 24Nm

38. Now you can reinstall the wheel! There is a specific way you should tighten the axle nut, pinch bolts, and caliper bolts to ensure everything is running as true and straight as possible, but I'm not going to cover that here.

39. Loosen the lower triple clamp bolts. This can be done without removing the fairing. Just be careful not to smack your ratchet against anything. You will have to move the fork legs however you need to get clearance.
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40. With everything loosened, spin the fork leg one direction only as you pull down. They're in there tight and, depending on your mileage, may be difficult to remove. Before removing the fork, I recommend cleaning all the dead bugs and dirt off of it. Slowly spin and pull and eventually the fork will kind of pop free. Slowly pull the forks out to avoid scratching that gold finish. Let's be honest, we all bought the S for the gold finish.

41. At this point I'm going to hand this DIY off to the Dave Moss video in the first post, which will be more hopefully than reading and looking at pictures. The only thing I'll say not to do that he does in the video is use sand paper to clean up the inner tube. The Ohlins tubes have a coating on the metal that gives it the gold. I'm 99% sure any sanding will begin to remove that finish on the metal. If you have any rust, I would say the most you can do is use a dremel with a buffing wheel and a little buffing compound, but don't take that as gospel.

This is what came out of my forks after 14.5k miles. I think most of it is dirt and grime that gets passed the seals. I didn't really notice any metal shavings.
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42. Now that your fork oil is all nice and fresh, put the forks back in the same way you took them out. Note: On the right fork leg there should be a piece of film that protects the fork and cables from rubbing on it. Make sure you spin the fork so that is in the right spot. I don't know why the left leg doesn't have that piece of film, at least mine doesn't.

You can put the forks in backward, but it's easy to tell which side goes where. The bottom of the fork leg can spin freely, this won't hurt anything, to my knowledge.

Fork leg height

As previously mentioned in the very beginning, take the extra time to ensure your fork legs are reinstalled at the same height! I recommend putting them back in the same height they came out unless you're trying to adjust your geometry by raining or lowering them, but that is advanced suspension tuning!

Measure from the top of the fork cap to the machined surface of the upper triple. I am assuming that these machined surfaces are almost exactly the same on each side. Mine measured at 23.05~mm on each side. Measure many, many times before removing and many, many times when reinstalling. Measure each leg in the same spot on each side, before removal and during installation, otherwise you could be a little off, but still less than .10mm off.

What I found easiest was to put the fork in slightly above 23mm, then gently tap on the fork cap with a deadblow, or similar soft surface hammer, until I got it as close as I could to 23mm.
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And there you have it. Fancy, fresh oil. Just changing the oil is relatively easy using the aforementioned Dave Moss method. Which is good since the Ohlins shop manual says every 5k miles!
 

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Wow! Thanks for taking the time to document and post this!
 

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I'm sure the standard forks have extra virgin olive oil that never needs changed. =P
Standard fork guys just ride. We don't even change the fork oil. We're so dumb that don't even know the difference between good and bad suspension.
 

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Dude!! You are fucking awesome for taking the time and effort to put this together! Thank you very much!
I take it the new forum doesn’t have the swear filters...:unsure:
 

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Discussion Starter #12
I decided to try out another method to change the springs more quickly based on a video I saw of an Ohlins tech changing springs at a race track. It didn't really work out for me because it can't be done with a headlift stand on the SS.

So, if you have two friends who can help pick the bike up by the front, or you're using ratchet straps to an overhead garage rafter to lift the front, then this method is much quicker and doesn't require removing the front wheel!

On with the basic method if you have two strong friends!

1. Remove the front mudguard. (I'm not 100% sure if this is necessary, it likely isn't, so long as the forks bottom out before the fender contacts the lower triple clamp)
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2. Remove the clutch and brake levers to more easily be able to remove the bolts holding the handlebars on. Lay down a soft cloth for each one to rest on.
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3. Remove all preload from the adjusters! Use something inside the socket to prevent marring the pretty blue finish.
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4. Loosen each upper triple bolt on each side. Unscrew them enough that there is no tension on them. This will make it easier to loosen the fork tops.
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5. Before this step is completed, you need to have the front of the bike supported. Either with an external lift system, or your two strong friends. If you don't take the weight off the suspension, the threads of the forks could be damaged and the suspension will drop once the fork caps are free! Unscrew the fork tops with whatever special tool you have for doing this. Unscrew them until you hear and feel a "clunk." This means that the threads are free.
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6. Gently lower the front end of the bike to expose the springs.
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This is why this method won't work with a headlift stand. This is as high as the fork tops extended out of the fork before the stand was resting on the front wheel. You will need the fork internals to be higher up to make swapping the springs much easier. At this point, you can follow the rest of the previous guide for changing the springs!

So, if you have strong friends, this method is much quicker since you don't need to remove the brakes and wheel.
 

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Excellent guide, thank you
I sent my forks into Ohlins for servicing BUT forgot to record the fork height in the triple clamps. Now I have it: 23mm 😀
I'm betting they are currently at a number lower than 23mm due to I like stability over quick steering with no noticeable loss of handling in the canyons
 

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Discussion Starter #14
Excellent guide, thank you
I sent my forks into Ohlins for servicing BUT forgot to record the fork height in the triple clamps. Now I have it: 23mm 😀
I'm betting they are currently at a number lower than 23mm due to I like stability over quick steering with no noticeable loss of handling in the canyons
So the triple clamps are sitting higher on the fork than stock, correct? Then yeah, lowering the triple clamps on the forks, so more of the fork sticks out the top would pitch the bike more forward, making it steer more quickly.
 

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Thanks for the thread even if I have the marzocchi fork but just a question.

1. Remove the plastic cover that screws into the lower triple tree to gain access to the steering stem hole. Lift the front of the bike using a stand. It is also recommended to have the rear up on a stand for stability. (Or other DIY method, i.e. ratchet straps on the upper triple to overhead rafters)
Where did you find the front stand which is specialised to access to the steering stem hole?
 

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Discussion Starter #18
Thanks for the thread even if I have the marzocchi fork but just a question.

Where did you find the front stand which is specialised to access to the steering stem hole?
I had one front stand that didn't work and they didn't sell a pin that would seem to fit. So I ended up buying a Pitbull stand and the correct pin.
 
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