Bladder conversion done differently

[Mark911]

It's been discussed that there's just not enough room between the shock and the rear subsection to incorporate a proper bladder system. There's just so much length and although going "fatter" might work with a piston type reservoir a true bladder needs to collapse radially, not axially, so you need length. So, you could hog out the fender or deform it with heat but you'll probably still have a relatively bad aspect ratio for a bladder. So I decided to solve the problem by incorporating a KYB bladder system onto one of my stock Alta WP shocks. It's been too wet (yes, in SoCal!) to test but it should work just fine.

 

[Fod]

Am I seeing this right? Do you have two compression assemblies in series? I believe the wp shock shaft is 2mm larger in diameter and probably about same length as the kyb (46mm shock I assume) so bladder/reservoir is capable of handling the displacement.

I am more familiar with mountain bike shocks and that said we use to tune bottom out with the internal floating piston (IFP) shocks with the air volume and pressure. I wish we could do the same with the ifp equipped moto shocks but I heard it doesn't have the same affect as it does with mtb. So might as well go with a bladder design.

 

[Mark911]

Not in series, in parallel. I had to add a completely new circuit from the main body to feed the second valve and then both dump into the reservoir through a shared port. I had to reverse the direction of flow through the KYB valving to make it work. I have NO IDEA how to valve it until I do some simulations, so right now there's no valving in the KYB housing (it's essentially plugged) and I use it for a fill/vacuum port. My initial thought is to utilize it as a "blow off" system but there's many other possibilities. But for now it's just a WP shock with a KYB bladder.

Yes, mtn/offroad bicycle suspension technology is way ahead of moto. The old Yamaha (tach forks) used something similar to what you mentioned and that was back in the mid 70s.

 

[OneLapper]

Last week I had the local suspension shop remove the SDI bladder kit on my shock and install a K-tech bladder kit. The body of the K-tech is 8mm shorter and does not have a schrader valve sticking out which made the SDI kit even longer. The length of both bladder kits is an issue, but the K-tech is a better fit.

Your design neatly solves the clearance issues!

 

[Rix]

It's been discussed that there's just not enough room between the shock and the rear subsection to incorporate a proper bladder system. There's just so much length and although going "fatter" might work with a piston type reservoir a true bladder needs to collapse radially, not axially, so you need length. So, you could hog out the fender or deform it with heat but you'll probably still have a relatively bad aspect ratio for a bladder. So I decided to solve the problem by incorporating a KYB bladder system onto one of my stock Alta WP shocks. It's been too wet (yes, in SoCal!) to test but it should work just fine.
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Got a ride report on this? I like it. may have to send you my shock and have you work some magic.

 

[Mark911]

Honestly, I really like it. It's still firm with my valving but it seems to be more compliant to small stuff and square edge hits. I've got a stocker, my Frankenshock and a Trax shock, time to do some side-by-side.