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Curious if anyone has tested or tried a different pull rod arm on their 16'-17' Ktm/husky? I've been riding a 17' FC350 since March and I really think this bike could benefit from a lowering link. Would really like some insight from someone who is currently running or has ran a different linkage setup on these bikes before I go ahead and purchase one.
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I used one on my TC 250 and felt it worked a lot better in the acceleration chop.
Before it was soft in the rear and squatted under acceleration, if I ran the adjusters stiff enough to stop that feeling it became deflective on acceleration. The circle continued with stiffer or softer valving and trying stiffer springs. With the link it seemed to find the happy medium with a stiffer set up that tracked well under heavy acceleration.
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Any links to said lower link(s)? Is this a Husky / KTM part or are you guys talking about a PC lowering link?
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I run the Pro Circuit system on mine. The main difference I notice is it settles quicker. It helps will acceleration / braking bumps and bottoming.
https://www.rockymountainatvmc.com/p/3585/64211/Pro-Circuit-Linkage-System?v=12675
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LumpDog841 wrote:Did you have to run a different spring rate with that setup?
I changed the spring anyway because I like cheeseburgers and beer too much. Not sure if it would have required it otherwise. I run more sag to get it to balance better and track straight (110-115mm). I suppose this linkage might have an effect that leads to the higher sag number working better.
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I was riding with ProCircuit linkage on my sxf450 16,5 FE and went from 45 spring to 50 spring with PC linkage.
It does make it feel totally different and doesn't lower rear that much. I don't see any reason to use just longer link but
PC set made it better. Rear was kicking both on gas and braking with stock setup. Anyhow I did run little with 17 model and stock was better than old stock setting so i didn't bolt PC linkage yet on before hurt myself.
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I run a Ride Engineering link on my 16' 450 SXF. Really settles the back down nicely. I'm running AER 48's on the bike 10mm up in the clamps. 105mm on the sag. Still corners awesome also. Settles right into ruts no problem.
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I run the PC linkage/bell on my 16. As recommended you have to go up two spring rates over whatever you would have run before.
I tried to get some clarity from PC about what the percentage of rising rate increase over stock was but even talking with Bones my question was not really answered to my satisfaction. I do find the linkage does add quite a bit more progressiveness and fluidity throughout the stroke and much more forgiving when it comes to a valving difference (even a not so good valve job still feels decent).
All around I'm extremely impressed. The bike settles better all around but the steering feels a little heavier than before....
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I doubt a small change in the linkage arm with make much difference in the linkage curve. However, changing the angle of the swingarm relative to the ground by lowering the frame will certainly reduce the anti-squat force, everything else being equal. That's like putting a lighter spring on the shock but you only feel the affect during acceleration. In addition, the lower anti-squat condition will add to the already lower rear end during acceleration giving the chassis a bit more dynamic rake and trail. During braking the bike should pitch forward a bit less thanks to the lower CG and the reduced anti-squat. However, traction might suffer somewhat. In general, the effect of changes to anti-squat are felt most in larger displacement bikes in good traction conditions where acceleration is higher.
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Pro Circuit's is more than an arm. It is the entire linkage which could change the curve quite a bit.
Take it to the limit, one more time!
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slipdog wrote:I used one on my TC 250 and felt it worked a lot better in the acceleration chop.
Before it was soft in the rear and ...moreerik_94COBRA wrote:Are you still running PC linkage or back to stock?
Actually traded her last week straight across for a 5hr '17 CRF 450. Loved that TC250 but couldn't pass on that deal. I was running the longer SDI pull rod, not the complete PC linkage.
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I went ahead and got the longer sdi pull arm and actually raced with it this past weekend at Lake Sugar Tree. What a difference the link made! The rear of the bike just settles into the corners so nicely now. I felt like stock the bike kind of wanted to just steer with the front a little too much, now the bike planes out much better and you can make a nice smooth arc into the corners. The way the bike handles now is exactly what I was searching for.
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I've got the 48 spring on the shock and at 230 lbs I get decent sag numbers, but the back end feels like it doesn't hold up for me. But I am off years of Suzukis plus, I just lightened up the forks a bit. Both ends feel ok, but not balances yet.
That said, wouldn't want the back end any lower for me.
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I forgot about this thread. Thanks for the info Shaun. Some interesting opinions on these things. I am confused a little on how it can lower the rear a bit but not affect setting up the sag. It also sounds like you would have to go up 1 or 2 spring rates.
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The process of setting race sag and then checking unloaded (static) sag is being replaced by a new one. This process sets race sag as usual but doesn't use static sag to help select proper spring rate. Now spring selection is based on actual spring preload. After setting race sag if you have 2 to 10mm of spring preload you're probably good to go. In most cases this process will yield a stiffer rear spring compared to the old method, sometimes significantly stiffer. Anyway, might want check your rear spring preload!
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Shouldn't have to remove the shock. Place a mark (piece of tape etc) on the main shock body 20mm above the adjuster. Now back the adjuster off until the spring just starts to rattle between the purches (bike on stand of course). Measure the distance between the adjuster and the 20mm line. The difference is the spring preload. Done. You can reverse this process to set the preload.
With this system of determining spring rate you can almost tell by just playing with the shock adjuster while the bike is on the stand. if you like a relatively stiff spring you should shoot for the lower end of preload, like 2-3mm. After setting race sag the correct spring will almost feel loose on the shock as 2-3mm preload isn't much!
If you like a slightly softer feel you'll shoot for a spring rate after race sag that'll be at the higher end, 8-10mm. However, even at this preload it doesn't take many spins of the adjuster to get the spring to rattle. You can roughy determine the number of threads per mm of your shock body and then count the full turns of the adjuster as well.
The final unload sag numbers can vary tremendously, 50-80mm are not unusual but are meaningless in this process.
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2017 Husky FC350 here...
Ran it stock for the first two rides, then put the PC linkage setup on it. Didnt go up in spring rate yet because the OEM spring was already too stiff for me. But as mentioned earlier, PC strongly recommends a stiffer spring.
OEM spring rate is a 4.2 right?
My weight calls for a 3.9
But with this link setup Im under the impression 2 sizes up is a 4.5?
PC told me to run a 4.9
Im not one to argue with them as they are the experts but I couldnt imagine running a 4.9 as Im already pretty comfortable with where things sit right now.
I'll be a pretty happy guy the day they eventually release a air shock as good as the WP air forks.
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How much you weight and what speed you are?
Stock sx350f was soft side to me so I went with 50N spring from my 450 setup on my new 350f. Its on stiff side
to me but working nice. Im at 78-80kg 175 pounds.
