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Gogoggansgo
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re:Aktiv And thru shaft

Out of curiosity what is the all the hate and or love about these two technologies. I'm curious my buddy has a fuel ex 8 "2018 MY" good bike but hell i don't noticed a massive difference with the rear shock over any of my setups. But what's the 411 now that thru shaft has been out over two years
 

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Thru shaft eliminates the IFP and associated IFP seal friction. But, it adds friction due the thru part of the shaft seal. Overall, maybe a little less friction. Not earth shattering.

ReAktiv is different. It's a blow-off valve that mainly functions in Medium and Firm modes. It works well, but still isn't "earth shattering". It can be tuned, but not without taking the damper apart. For my money, I'd have it tuned to be more effective in Medium mode...and just might.
 

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Until recently I've been riding my '18 FEX8 in the medium setting 90 percent of the time, using the open setting only for long, sustained gnarly downhills. Sometimes not even then. Lately I started using the firm setting for climbs and I've started liking the poppier pedal feeling and the ability to upshift a cog or two and climb a little faster. Also started experimenting with leaving the shock in the firm setting for moderately rough downhills, and letting reAktiv do it's job. It's firm, which I like, but not harsh. I can feel it open up on the bigger hits. It's almost like riding a different bike. I mean that in a good way. And I still have open and medium when I really need them.
 

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Hey, I was wondering a similar question, although it might be discussed elsewhere here in the forum already. So, please be kind to me ;) or maybe provide a linke where it was discussed.

So, I have a '19 FEX 8 (23"). I found a thru-shaft re:aktiv shock from a 9.9 in an online-marketplace and checked whether it would fit in my bike. And luckily, it did. My chainstay link already had ball bearings, as well as the upper link of the rocker. So I figured to give it a try. I bought the required bolts (4x W561881) and the washers for the upper trunnion mount (2x W529969).
The shock fits perfectly and is able to pivot around the bearings (tightened and torqued top and bottom mount separately and checked if the shock gets stuck or sees some stress).

Around SAG, everything works fine. However, when I go deeper into the travel (~ 50% of travel, eyeballed) a cracking noise develops. I checked everything at least three times but I can't get rid of the cracking noise. Obviously, something is not working as it should...

Has anyone any suggestions? Maybe someone could provide a detail-shot of the mount situation of a 9.9 top and bottom shock mount? That would be really appreciated! Thanks!
 

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So, for future references... I fixed it.

Although being very careful when installing the shock and paying attention to not mechanically stress the shock when bolting down, I must have induced some kind of stress. I checked everything again and adjusted the lower shock mount distance to accurately 50mm. Now everything works as it should!
 

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Sorry... my post was misleading.

I untightened the lower main pivot bolt to get a little more space for the shock. I needed 50mm but with the bolt torqued to 16 Nm, I couldn't get the shock in. So I loosened the bolt a little to get approx. 0.5mm between the lower shock mount. This did the trick and I could get the shock in. After that bolted everything down with the correct torque.

The shock can still pivot freely around the lower shock mount; however, I guess a little stress is put on the lower shock mount now. Seemingly, this doen't affect the function of the shock, since it worked flawlessly at my first ride today with it.
 
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