The problem I'm trying to solve is that my Pino tandem came from the factory with a Spinner GRIND fork
, which cannot possibly be as strong as an off-road MTB fork. It's a piece of crap, same as the 20" RST forks (sorry JanMM). I'm not going to throw it out, but I know it will not last more than a few years. The bushings are already starting to wear.
I'd love to use a MEKS Carbon
fork, but its huge fork crown is known to have frame interference problems on recumbents. Basically, at full compression the crown crashes into the recumbent tube, with associated cracking not to mention steering disasters.
The White Bros. has a recommended maintenance interval of 30 hours
between dissassembly, cleaning, and re-greasing. Every 100 hours it needs complete service of all seals. Sounds like maintenance hell for a touring bike that's used 7 hours a day for two weeks - that's three teardowns and a seal service right there.
I agree that the caution is warranted. Chopping and re-welding fork legs at a qualified shop is probably less of a concern than the toughness of the fork crown. The good news is that shortening the fork for 20" wheel use will reduce the torque stresses on the fork, and I suspect that fork crowns designed for off-road hits on 26" wheels will see lower stresses from on-road tandem use on 20" wheels.