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Discussion Starter #1 (Edited)
Just a wee intro. The posts below are copied from my Modifications thread where with the much-appreciated help from @JohnT and encouragement from other forum members I took the plunge and installed the fork cartridge upgrade myself. There are significant edits in the following posts to make them more suitable for a DIY. In truth the install is a lot more straightforward than I'd originally thought, the hardest part was compressing the spring, and also not swearing when I discovered the supplier hadn't sent enough fork oil.... ;)

The usual disclaimers apply. I'm a very amateur mechanic with average (at best) mechanical skills. The below install is how I went about installing the fork internals and I provide the information in good faith. Neither I nor this forum will accept any responsibility for accidents or mishaps from following the guidance in this DIY thread. You do the work at your own risk. Worked fine for me though! :)

If in doubt, always get a properly qualified person to do the job.


Firstly get preparations underway for the fork upgrade. The object is to get the front end in the air so the forks can be lowered through the yokes. You might have a font paddock stand or some other way of achieving this however this is what I did. With combination of the ABBA Superbike Stand (which lifts the rear wheel off the ground) and a hydraulic jack to lift the front end up by putting some wood under the sump and jacking it up. Then bricks were used as a more permanent support as I don't trust hydraulic jacks to stay up for any length of time. Result seems stable and pretty strong. Both wheels are about 8" (20cm) off the ground. Here's a couple of photos showing the fun!








 

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Discussion Starter #2 (Edited)
Front End Strip

The name of the game is trying to get these into the bike forks:



And so it begins - here we go!

Firstly the brake calipers need to be removed to allow for front wheel removal.





Note that the wheel speed (and ABS) sensor has been disconnected and is hanging free.


I suggest that you (like me) leave screws and bolts lightly re-attached to where they came out of once the parts have been removed so reassembly is easier and parts don't get lost.


For example, here you can see that I've used masking tape to hold the caliper bolts to the brake caliper and the Roadlok brake lock.





Off with the front mudguard.





Gone...






Here's the axle removal tool to used to unscrew the quick release axle. Only a few pounds from fleabay, but you can make your own. ;)






Remove the wheel.





Now it's just a matter of loosening the fork yoke (triple tree) clamp bolts, but it is a good idea to photograph the top of the forks so you know how many lines are showing at the top of the clamp so you can keep the fork geometry the same.




Firstly slacken the upper fork clamps (one bolt each side).

You are now faced with a decision. You can take the opportunity to slacken the fork tube top nut whilst the lower fork clamps are still tight, or you can continue and just open the fork caps using a vice later on. If I had to do this exercise again I'd choose to loosen the caps at this stage as it saves on risking damage to the fork tube finish, but it's up to the individual.

Loosen the lower fork clamps.





A tip is to use a large flat blade screwdriver in the slot of the bottom form clamp and carefully twist the driver to widen the gap, but keep a firm hold of the fork leg,to guard against the forks falling through the clamp, probably scoring the forks in the process. As it was they were removed unmarked. It might be better to use a wooden or plastic wedge rather than a screwdriver as this will lessen the chances of marking the clamps.


Remove the fork leg.





Remember to remove the wheel speed sensor bracket from the left hand fork leg.





Finally the left fork leg is removed and we have a 1200cc monocycle!





The forks are ready to be stripped and new cartridges fitted.


 

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Discussion Starter #3 (Edited)
Taking apart the front forks

Now it’s time to take the forks apart.

If you haven't already loosened the top fork tube caps, I suggest you do as I did below:

First of all, I fitted soft (rubber faced) jaws to my vice, and then wrapped the fork legs in some cardboard where I was going to clamp them (credit to @Gambo916 for this tip). Wrapping the fork legs in rags might work as well, but I think the method I used is superior (just my opinion). Be careful not to over-tighten the vice as you might distort the fork tubes.





I decided to firstly loosen the top caps, this took a few attempts. Not because the caps were on really tight, but because I was wary of over-tightening the vice and risk damaging the fork tubes, so the first couple of times the tubes turned in the vice so I tightened the vice 1/8 of a turn and tried again. This took 2-3 attempts (can't remember) before the caps loosened.





I then swapped my attention to the bottom of the forks. The right hand fork needed the axle clamp bolts removed so I could get to the bolt holding the damper cartridges in place.





For the left hand fork, the threaded bush has to be removed as well as both axle clamp bolts.





I had a container at the ready to catch the fork oil when I removed the lower bolts...





And 45 minutes later the internals are out of the forks....


 

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Discussion Starter #4 (Edited)
Installing the new cartridges - Part 1

So now I get to play with my new toy - the fork spring compressor! You can probably get away without this if you get the help of a friend (so I've been told) but getting this tool makes the process much safer and a one-person job.


In my case I am installing an Andreani fork cartridge kit in the front forks, other fork kits should be pretty much the same process I imagine.


Here is the fork spring compressor set up and ready to roll...





Here are the beauties I'm going to install....





Mmmmmm....fully adjustable goodness!





The compressor is really easy to use. You locate the fork bottoms in the clamp and adjust the clamp so that the clamp threaded pins locate in the collar holes at the top of the fork springs, then you just use a wrench to operate the compressor.

First the fork springs had to be removed by taking off the fork caps off. This is where the spring compressor earns it's keep.





And after some mild spannering, the fork cap is removed...





Now the new fork cartridge needs secured to the fork bottoms using the bolt that comes with the Andreani kit (bolt smaller size than the stock cartridge bolt). Just needs screwed into the bottom of the fork. A word of caution here, make sure you get washers with the fork kit as I didn't. I have reused the original ones which probably isn't advisable but so far no oil leaks, and there did seem to be a dinky little o-ring on the washer as well.





Now we are at the stage where I need to set the fork oil level.

I will also need to bleed the new dampers to remove the air from them. Andreani don't mention this i their instructions, but I can't see how this would not need to be done.
 

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Discussion Starter #5 (Edited)
Installing the new cartridges - Part 2

Had another spare hour tonight so I kicked on with the fork upgrade.

Firstly the fork spring was removed from the fork in preparation for setting the fork oil level. The manual says there should be a 100mm air gap above the oil but I'll start with more of a gap than this as like @JohnT says, it's easy to add more oil if needed. Different fork kits will very likely have different oil level recomendations so consult the appropriate documentation for the setting, and then it's up to you if you adhere to it or not. If in doubt, stick with what the manufacturer recommends.






So to start off with I poured in roughly the right amount of oil into the fork using a tape measure as a dip stick. I erred on the generous side as the oil level tool will take care of any excess. Then I purged the air from the damper by raising and lowering the damper rod until the action became firmer and smooth, plus all the bubbles stopped coming out, then gave the damper half a dozen more strokes just to be sure.

Up........





And down (then repeat! lol)....





Then the next toy comes into play. The fork oil level tool. Basically a syringe, a clamp and a graduated hollow rod...





So, you set the tool to the amount of air gap you want (in my case 140mm) and then place the hollow rod in the fork and let the clamp body sit on top of the fork (set in the fully compressed position).





If you have more oil in the fork than the level you have set, then when you suck with the syringe you'll get oil in the syringe till the oil reaches the correct level, then you'll suck air. If you don't have enough oil in the forks then you'll suck air and no oil will come out (or you have fluked the exact oil level). I'm no expert but I guess the correct method is to always have slightly too much oil in the fork as then you'll easily know when the tool is telling you the oil level is correct.

So as I was generous with the oil, I did indeed get some oil in the syringe before it started sucking air.





The oil was put back into the bottle to be re-used (Ohlins oil is expensive!)


Then the fork assembly continued. First of all bit of string was tied to the damper rod to ease assembly as the rod will fall down inside the spring and will be a pain to retrieve. The tip suggested by JohnT stops all sorts of cursing I expect!





The string was then threaded through the spring and the spacer before the components were installed in the cartridge assembly...





So again the fork spring compressor earned it's keep and compressed the spring to enable the fork cap to be installed. Once the cap has caught the threads of the damper rod, the string can be removed.





Then the lock nut was tightened onto the top cap....





The above differed from the Andreani install instructions as the fork cap on my forks were different to the ones shown in the instructions. The fork caps in the instructions had far longer collars underneath which meant they extended into the fork springs and needed a thin spanner to tighten them. My fork caps (as you can see) could be tightened with the spring compressor used to expose the lock nut on the damper rod.

I've only done one fork, the other will be done once I have ascertained that the fork that I've just rebuilt isn't leaking oil out of the bottom bolt. Leaving the fork overnight with no seepage from the bolt will be a good initial indication that all is well.

Anyway here's the almost completed fork in all it's glory....


 

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Discussion Starter #6 (Edited)
Just when you thought you were finished...

I decided that today was going to be the day that the fork assembly would be completed. I had the afternoon to myself, and was full of confidence.... Well apart from one niggle at the back of my mind that I was trying to ignore....

So anyhow, I firstly double checked that the rebuilt fork was not leaking oil. I had left the fork sitting upright overnight with some kitchen paper below it to catch any drips. When I checked the next afternoon the paper was unmarked and when I felt around the bolt area at the bottom of the fork it was dry as a bone. Looks promising!

Another task that can be done at this stage is to set the default preload setting. So Andreani specify 4 turns from fully out. So I firstly ensured the preload was backed out fully, then it was a simple matter of counting 4 clockwise revolutions of the spanner and job done.

Below you can see I held the fork cap with a pipe wrench (jaws wrapped in tape to prevent marking) and a socket on a T-handle did the turning. This pic is slightly misleading as it shows the top caps screwed fully in! I forgot to take the pic at the right time so this photo is really just to show the set-up I used to set the preload.




Before screwing the fork cap fully home, I backed off the damping adjuster just in case it would be put under any stress.


Once the fork cap was screwed fully home, I then gently screwed the damper adjustment fully in (clockwise) until the allen key wound not turn any further, then backed it out by 2 turns which is the recommended base setting.





One fork leg done! :)


The other leg should have been just as straightforward.....


The damper installation went fine, but then that wee niggle in the back of my mind became a reality. I poured the remaining oil into the fork...... but there was not enough of it.... :( I had thought this might have been the case when I looked at what remained in the oil bottle after the first fork had been filled and it looked to me as if it was going to be a close call. Bear in mind that this is with me using less oil than the instructions recommended (because I'm using a larger air chamber gap) so I'm slightly miffed at the supplier not giving me enough oil to do the job. I checked the oil level roughly using a tape measure and it was around 20mm short of the 140mm setting I wanted...

To be honest I've sat on the cartridges for a couple of months now, so I'd be up against it to complain now after so much time has passed, and then have to wait for the issue to be resolved after a possible war of words. I've just bitten the bullet and ordered some more oil and be done with it. The oil should arrive by mid-week, and I'll complete the install then.


Just as well I'm not in a hurry.... ;)
 

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Discussion Starter #7 (Edited)
Installing the new cartridges - Part 3

The new bottle of Ohlins oil came, so off I trotted to the garage to complete the work on the second fork. Glugged what must have been 20ml into the fork to achieve the correct level, which was a bit of a sickener since I had to buy an additional 1L of oil to complete the job. Having said that I have spare oil should the oil levels need to be raised.

I built up the fork using the same process as the previous post but tightened the cap to the damper rod with the aid of a nifty new spanner rather than the pipe wrench. It is made from a plastic composite material, which won't mark the fork caps.













Now install the fork legs back in the yokes. Tighten the bottom fork clamp bolts but leave the top ones loose for now.






Finally reinstall the wheel sensor, install the front wheel (don't tighten the axle clamp bolts up) and front mudguard (leaving bolts loose). Install the brake callipers.
 

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Discussion Starter #8 (Edited)
Finishing off the installation

Acting on the advice from @JohnT a good way to ensure correct alignment of the forks is to bottom them out and then tighten the axle spindle and bolts in that fully compressed position. Previously on my bikes I had just bounced the front end a few times and then tightened the fork bolts. I’m sure that would have been ok, but this new method sounded better.

I used my front wheel-chock to hold the bike upright and this seemed to work ok.

So here is what I did next...

Firstly the tank was covered with a thick towel to prevent any damage...







The handlebars need moved out of the way to allow for the springs and caps to rise upwards as the forks compress.





The bars were carefully rested on the tank. Note that only the front set of bolts have to be removed from the fork clamp to release the complete handlebar/clamp assembly...







I now used a hydraulic jack (with a piece of wood) under the engine sump to raise the bike enough that the forks became fully extended, which removed some pressure from the front fork springs.The fork caps were now unscrewed without any drama.

Using the jack, the bike was gently lowered until the forks bottomed-out...







I watched that the fork springs didn't foul on any of the handlebar cables or hoses as I lowered the bike....







Then the left fork leg was firmly but gently moved backwards and forwards until it found it's natural resting place. The front wheel sensor seemed in a good position so that was left alone. You might find that you have to move the threaded sleeve in the left fork to obtain an acceptable clearance for the sensor. Then the spindle bolts were tightened, followed by the mudguard bolts.






Next the bike was raised up and the fork caps were screwed back on fully, and the top fork clamp bolts were then tightened. Handlebars went back on and the bike's front end was then bounced a few times to make sure everything seemed smooth. All appears OK and the front forks are certainly a bit firmer than the stock ones that were removed.


All bolts were then checked for tightness, though I doubt the bike will be used before the tubeless wheels get reinstalled.

When you think you've tightened every bolt, check them all again. Pays to be safe when you are messing with suspension, brakes, steering and wheels!

Then you will need to set the front end sag, which I'll cover in a separate thread when I get around to doing this. If you need help with this before then why not ask in the forum, or google the information on line.

Final setup (for me) will be when I get my tubeless wheels on the bike and then tweaked after a few test rides in the Spring.

End note. For folks that are going jump on their bike and try out their nifty new springy bits straight away, please check the operation of the front brakes before riding away. Remember the calipers have been off the discs so the pads might not be correctly positioned. Probably a good idea to check clutch operation too.
 

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This being one of the mods I would consider doing, there is no way I would have the patience. Guess one of the things I need to do this winter (in addition to buying another NineT) is find a shop with enough experience to do this. Kudos to you Dave, for having the confidence to take on a new project like this.
 

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Discussion Starter #12
Folks, this DIY is hopefully complete. Could you all do me a favour and proof-read it for me? Think I've ironed out most of the typos, spelling and continuity mistakes, but normally a fresh pair of eyes will see mistakes I've become blind to! Just reply in this thread and when all errors are fixed I'll clean up the thread. Thanks! :)
 

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@BaldyDave, great to see you had the guts and motivation to dive in and do this for yourself....and I'm guessing you're now thinking it wasn't a daunting as you'd first imagined?

Hopefully this helpful and well explained thread will encourage others to have a go at fitting cartridge kits themselves.

Good on ya Baldy!
 

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Discussion Starter #15
after look at this, i think i will buy complete ohlin front forks instead
Fair enough, we all have our limits with what we are comfortable with doing. :)

For me the bike is off the road for the winter so I could take my time, plus I had the help of the forum to back me up and also a mechanic on standby if I managed to stuff anything up. Thankfully it all went reasonably smoothly and it wasn't as daunting as I'd first thought (cheers @Gambo916). On the positive side, the entire job cost me around £550 including tools and extra oil, and about 3 hours of my time, plus the satisfaction of doing a good job and knowing that it has been done right.

I'm totally sure the Ohlins forks will be fantastic, and probably a bit better than my setup and much easier to install. Obviously a lot more expensive, but hey if you have the money, why not! :)

I'm content that I am probably getting a lot of bang for my buck, but I'll never criticise anyone for taking a different path. :)
 

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Hi BD, congrats! And thank you for this DIY, this forum has more info now!
 

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I just received this exact same kit from Italy today . Does it require buying 2 Liter bottles of Ohlins Oil or is 1 sufficient?

Bravo for this thread and the precise documentation.
It's people like you that help people like me move forward on a project like this.
Thanks again
 

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Folks, this DIY is hopefully complete. Could you all do me a favour and proof-read it for me? Think I've ironed out most of the typos, spelling and continuity mistakes, but normally a fresh pair of eyes will see mistakes I've become blind to! Just reply in this thread and when all errors are fixed I'll clean up the thread. Thanks! :)
Hi BaldyDave,
I can't see where you mentioned setting the cap positions in relation to the damper rods, so I apologise if I have missed it.:goodjob:
I have just fitted these internals and the instructions said to top out both rebound and compression adjusters with the allen key and then wind them in 4 full turns before fitting the caps to the damper rods, you then thread them onto the rods until they just meet resistance, this is now when you lock the cap to the rod with the lock nut. Doing this gives you 4 full turns out from fully closed to adjust the damping. I read elsewhere that others have suggested to set them so that you have 6 turns as the tapered end of the damper rod doesn't fully clear the orifice at 4 turns. Also they suggested using 2.5 weight in the compression leg as this helps higher speed jolts to be dealt with. I have set my air gaps at 150mm, as you said it is easier to add than to remove oil.
This is the way that I have set mine up and I am just waiting for a dry day to test them out.
Regards, Phil.
 

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Discussion Starter #20
@Need2c2Believe Phil thanks for the additional info. Look forward to see what your feelings are when you get the bike out on the road. My bike is still in it's winter slumber and still needs the suspension fully set up with sag etc.

I stuck with the recommended 4 turns out and have used the same Ohlins oil in both forks.
 
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