CURRENT MILES
22,022
THE WHY:
This is for the same reason I just did the Fork Springs. You can go back and read that in full, but I’ll copy the important stuff here. What you do to the front you should also do to the rear, right?
When my 690 left the KTM Factory it was setup for a guy weighing 165 to 180 pounds. Obviously that guy is not me. I’m currently tipping the scale at 235 pounds (naked).
KTM also did not include in their factory setup was anything you might bolt on to the bike (crash bars, luggage racks, skid plates) and then what about all the actual luggage for a trip? I run a full Mosko Moto Reckless 80. The bike should be sprung for the actual weight it’s carrying, on the ride you want it best to perform on. For me that would be a fully loaded BDR style ride.
Just like for my forks Slavens has a great selection of the proper springs https://slavensracing.com/shop/shock-springs-61mm-x-220mm-ktm-690/. I gave them all my numbers and they suggested that I go with the .10 spring rate. If you do the math I fall right in the middle of that 254 – 276 slot.
I ordered the springs the same time as the forks. Unlike the forks I didn’t need seals or internals as my shock seemed to be in pretty good condition.
THE INSTALL:
To pull the shock out of the bike means that the gas tank has to be moved up and out of the way first. So let’s start there. (seat and side covers are already removed – as part of the larger project)
- The tank is held on by three mounting points. The two at the top under the side covers and the through bolt at the bottom.
MY TROUBLESOME TOP BOLTS
Back when I was doing the SOCAL BDR with Mike I had to turn around one day and head into town as my two top bolts had come loose and one of them was missing! Both of my top bolts are screwed up. Both have broken free of the frame.
One of them has the original bolt still, but the welded nut is no longer welded.
The other is sporting a bolt from the hardware store. It’s the correct thread, just not the right style, but it to is no longer attached to the weld and as a matter of fact I lost that piece completely.
Either way, they seem to hold tight into the larger special bolts coming in from the other side so I’m not too worried.
Back to taking the shock out, these two bolts need to be loosened. You are going to want the tank to pivot on these two so back them off quite a bit.
The bottom bolt is an upgraded through bolt. It also serves as part of the exhaust hangar. This one needs to come all the way out.
Next up, we need to make room for the tank to pivot. I took out the ECU and then disconnected the fuel line. The fuel line is an easy quick disconnect style. It takes just a puch of the clip and a little wiggle. Speaking of which, now is a good time to swap out that little itty bity fuel filter (white arrow).
With that done we can tilt the tank up towards the handlebars. I used to hold it up with a bungee attached to my mirrors but now my GPS mount seemed to be the perfect attachment point.
Now I was ready to get to the shock and spring.
There are two bolts holding in the shock/spring unit. Both are T-50 Torx.
The top one is on the left side and screws into a threaded nut in the frame.
The lower one is under the bike in a place where the bike would normally be sitting on the work stand so it had to go onto two wheels and then I held it upright on the spools. I could have done it on the kickstand too but I like a more stable platform.
The Bottom T-50 is accessed from the right side of the bike.
IMPORTANT: With the bike on two wheels, when you remove the shock there will be nothing holding it up. It will want to collapse to the ground. I used a small floor jack to prevent that from happening and to take any weight off of the unit when I went to pull out the two bolts.
Once I pulled out the bolts, I could then let it drop and get the floor jack out of the way. Here’s the shock ready to pulled out.
Here’s the shock / spring as it came out of the bike. You can see the two mounting bolts are the same.
I checked the shock ends for free play and there was none. Both were filthy, but tight. Yay me! I had replaced the shock lower bearing just a year ago
Next on the work bench I first backed the spring preload rings all the way off. You might have to use a hammer and punch to get them unlocked but then it’s best if you use a hook tool. I have a few and this is the one that seemed to fit best.
Next, I gently clamped the shock upside down in a vice. The spring needs to be compressed and then the retaining collar can be pulled out.
BUT FIRST A WORD OF THANKS!
I have an old fashioned car spring compressor or two in the garage. That’s how I would have done this next job. But my new friend Charles had a much better tool that was specifically built for the job and offered for me to borrow it – heck he even delivered it!
Thank you, thank you, thank you!
Thanks Charles – that really made the work so freaking easy! Motion Pro makes great tools too!
With the shock in the vice I used a screwdriver to push the Bump Stop down the shaft.
Next I grabbed the super tool. You simply attach the tool center pin through the shock mount hole, slide the silver wings into the gap between the spring and the collar, turn the nut on the shaft with a crescent until you have enough space to pull the collar out and that’s it! Nobody looses a finger or an eye. Winning!
With the spring off the shock I took the chance to clean and inspect everything on the bench.
As I said before I checked the mounting pivots in the shock body for play but on the bench I took a much closer look and they were just fine.
I put the shock back in the vise and started reassembly.
I noticed once I had the shock on the body with a little compression, that the spring wasn’t sitting flush against the preload adjustment washer. There shouldn’t be that gap in there.
That’s not right. So I took the whole thing apart and swapped ends on the spring. While both ends looked to be identical, they were not. One end was just a little bit bigger than the other.
I checked to make sure the collar fit inside the smaller end and it did and so the whole thing went back together. As I was putting it back together I actually stopped and thought long and hard about an Xtrig. Now would be the right time, IF I was going to go that route.
These things make setting your sag so easy. They are a bit expensive for what they are (just under $200)and realistically you only use them once – or at least that’s what I would do. I put a Wanted ad up in ADV just to see…
So for now, XTRIG-less, I guessed at where the new spring preload setting would be for now and installed it back in the bike.
Torque settings for the two T-50 bolts are…
Next I would have lowered the gas tank and reinstalled the bolts but my next project is replacing the Fuel Pump so we’re going leave it there for this post.
He's an avid hockey fan, rides a mountain bike, sometimes rides a road bike, has a few motorcycles (he had a really fast one, had a big cool orange one, rode a really slow one, and is currently building a perfect "BDR Weapon"). If that isn't enough, he makes cheese and sourdough bread, loves strong beer and good red wine, and poorly plays the Mandolin.
- My Pre Nor Cal BDR Settings - September 15, 2024
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- Studs > Bolts for the Rear Rack - September 5, 2024
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