nice bike and very good job on the full restoration
It's from 1996, as there isn't a lot of documenation about Kästle I'm happy to share a few bits
The test result (picture from Google translator) isn't great, but this is only a matter of the a bit cheaper components in particular the suspension Fork to provide an attractive price
The higher equiped Kästle FS had all Marzocchi MX or DH forks. I would give it a try with a better fork, maybe even up to an early Bomber...
let me share again some info, I do appreciate if a bit more attention is spend with regards Kästle bikes here
Info from an buyers guide 1996
Ad from 1996
A Marzocchi DH3 fork was original equipped, a bit surprising and outdated for 1996, no ahead set was used.
As mentioned at the ad, the bike came with the interesting brake system.
Maguras with specific Kästle brake pads with tooth, and specific rims fitting to this.
I've never used something like this, but the idea was mostly to increase the surface between the pads and the rims.
In particular this will be hard to get somewhere these days.
The iconic Kästle cranks do come up once in the while at ebay or classiefieds, just mostly overpriced.