KYB High speed adjuster nut spins much easier after shock service?

Hello, I recently serviced my KYB 46mm shock ('99 KX250), changing the oil and new seal head/bushings/bladder etc. Done it before with no problems but I had never had messed with the high speed adjuster nut before. I decided it was time to learn about it so I took it out during the service, being very careful how everything came apart, cleaned and carefully re-assembled. Now that the shock is completely back together (except still need to get the nitrogen filled), the low speed compression clicker seems to work fine, and the high speed nut spins the normal 3 -1/4 or so turns, but if I am at more than 2-1/2 turns out with the high speed nut, it turns very easy, even by hand. Not spinning completely free, but getting pretty close. If I am more than 2-1/2 turns out on the high speed nut and try to adjust the low speed clicker, it spins the high speed nut with the clicker. I can hold the high speed nut with a wrench while I adjust the low speed clicker, but I never had to before. If less than 2-1/2 turns out it stays put, but any more and it gets pretty free, making me wonder if it could vibrate/move while riding. I feel confident that it went back together correctly, it really wasn't that complicated. Any thoughts? Thanks in advance for any help or response.

How many psi do you have in the shock? I assume you've just filled with air before getting charged with N2. If not, then I'd expect the whole lot to firm up once its got some pressure on it. Does the HS still stop where its meant to, but just turns easily?

Jakobi, thanks for responding, I only have about 10~15psi in the bladder right now, just enought to keep the bladder seal head and shock seal head up against the circlips when I was bleeding the shock. I was also wondering if a full nitrogen charge would affect the high speed nut spin resistance, but this was my first time dealing with the high speed adjuster so I wasn't sure. Yes the high speed does stop where it is supposed to, it just spins easier than before (with a full nitrogen charge). I will get the bladder filled tomorrow so hopefully that will firm things up. Thanks again.

Jakobi, thanks for responding, I only have about 10~15psi in the bladder right now, just enought to keep the bladder seal head and shock seal head up against the circlips when I was bleeding the shock. I was also wondering if a full nitrogen charge would affect the high speed nut spin resistance, but this was my first time dealing with the high speed adjuster so I wasn't sure. Yes the high speed does stop where it is supposed to, it just spins easier than before (with a full nitrogen charge). I will get the bladder filled tomorrow so hopefully that will firm things up. Thanks again.

 

As long as you can still turn it CW and it stops you'll be fine.  I thought you kept turning it and it wouldn't stop... because I had that happen when I turned the adjuster (out of the shock) CCW a bunch and the mechanism locked up inside.  I couldn't turn it enough CW for it to stop.  Essentially the mechanism inside was rotating as a whole, instead of preload bit threading back and forth on the HS adjuster nut.

The whole thing is likely down to the fact that the O-ring on the adjuster isn't dry like it probably was before the service.

Just to follow up, I filled the bladder with nitrogen today and as Jakobi predicted, it firmed the high speed adjuster nut back to its original feel. Everything feels normal again. I will know in the future to expect it to feel loose before recharging. Thanks again for all the responses.

Thanks for following up. Makes the thread useful to us now, and those in the future. Cheers

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