Judging shock damping based on extension speed?
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- John Stimson
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Judging shock damping based on extension speed?
I just received a brand new set of Koni Sport shocks. One of the rear pair will fully extend from the compressed position in about 15 seconds, when set to full stiff. The other one of the rear pair extends extremely slowly when set to full stiff. If I take a full turn out of the rebound setting, then the extension speeds match. With the out-of-the-box settings, they both extended at about the same, pretty fast, rate. It seems like a damping mismatch is more likely than a gas pressure mismatch. Is this a problem, or just an irrelevant effect that won't affect performance? Does ProParts do Koni warranty work, or would they need to go back to Kentucky?
Re: Judging shock damping based on extension speed?
John Stimson wrote:I just received a brand new set of Koni Sport shocks. One of the rear pair will fully extend from the compressed position in about 15 seconds, when set to full stiff. The other one of the rear pair extends extremely slowly when set to full stiff. If I take a full turn out of the rebound setting, then the extension speeds match. With the out-of-the-box settings, they both extended at about the same, pretty fast, rate. It seems like a damping mismatch is more likely than a gas pressure mismatch. Is this a problem, or just an irrelevant effect that won't affect performance? Does ProParts do Koni warranty work, or would they need to go back to Kentucky?
OTS (off the shelf) Koni's are typically pretty close out of the box. You would really need to have them dyno tested to see if the shocks differentiate from one to the other. We do not offer any OTS warranty programs, you would need to contact Kentucky.
- John Stimson
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Re: Judging shock damping based on extension speed?
Based on my simple test, the two fronts are pretty close, and the one rear is pretty close to the fronts (the rear that extends slowly when set full stiff). I wouldn't describe the other rear as being pretty close. Sounds like maybe they're going back to visit Kentucky.
- KJ Christopher
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Re: Judging shock damping based on extension speed?
They may send a replacement out to exchange if you're in a hurry.
kj
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Use the email link. I don't read nor get notified of PMs.
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Re: Judging shock damping based on extension speed?
You have no way of knowing if an air bubble is somewhere in the valving from the shock being shipped on its side. That's why shocks are cycled on a dyno for a a while before any real measurement takes place. As Jeff said Konis are pretty good right out of the box. You might have a bad shock but your test won't prove or disprove that.Is this a problem, or just an irrelevant effect that won't affect performance?
Re: Judging shock damping based on extension speed?
John,John Stimson wrote:Based on my simple test, the two fronts are pretty close, and the one rear is pretty close to the fronts (the rear that extends slowly when set full stiff). I wouldn't describe the other rear as being pretty close. Sounds like maybe they're going back to visit Kentucky.
If it were me, I would have them dyno tested to see if you can obtain any evidence to present your case to Koni or the original retailer you purchased the product from. If you contacted the original retailer, you might be able to ask them to exchange the shocks for another set.