The thing with suspension forks is that they are not at maximum extension all the time. they are usaully sagged from the start. and then they get shorter when you ride up and down bumps.

so there is no need to look for a very long fork to replace with.
when you go down in millimeters from like 470 to 400 or so, the head angle will become 2-3 degrees steeper. and this is good, this is what you want, and now it works on the road.

All my bikes seems to ended up at 72-73degrees HTA, and the trail is adjustable with rake. there is a trail calculator online. where you can put in whatever values you like. and see what happens.

but its all irrelevant imo. you put on a new fork and ride it. and in like 3-4h it feels like you have never ridden any other bike.

HTA determines the RATE of steering, that is how much input is needed for certain result. and this can also be adjusted with stem length and handlebar length.

trail determines handling. short trail is low speed stable and high speed instable.
long trail is high speed stable and low speed unstable.
in between is a bit of both. or neutral handling!

you will get inbetween by default by getting any available steel fork for your suspension frame. imo.

Bicycle Trail Calculator | yojimg.net

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