[pete]

It's quite simple with the older damping rod style...

easyest way................
pull the forks apart and put spacer tubes over the damping rods..
& shorten the springs.. but the compression damping most lightly won't
work...

not so easy way....
cut the bottom of the damping rods... weld a short bit of solid rod in the bottom
then re-drill and tap for the bolt..then re-drill the rebound damping holes up the
damping rods the same amount you cut off... you will retain both compression
& rebound damping... you don't have to shorten the springs....

If they are USD forks thing get a bit trickyer...




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