Hello frame building ladies & gents.

I know this question has been discussed before, but when I do a search, I get ten-gazillion threads on trail riding. So pardon my (vast) ignorance, but please explain to me in newbie terms exactly how the head tube angle and fork interact (or don't) to create trail. If I understand correctly, more trail makes the bike more stable, less makes it quicker handling (within reasonable parameters). Since "modern" bikes use far (FAR) steeper head tube angles than bikes of my youth, they should be more difficult to ride with no hands. I may just be getting old, but that does seem to be the case.

So below are two illustrations that I crudely made in MS Word. The first is intended to illustrate a bike with forks essentially parallel to the head tube, the second a bike with the forks raked at an angle to the head tube. If it is the angle of the steering tube to the vertical axis of the wheel that determines the trail, then both bikes should have the exact same trail, and should handle equally. If, however, the rake of the forks changes the effective rake of the head tube, then the "raked" fork should provide more effective trail and handle more stably.

Which is correct, please, and why?



OK - Having Googled some diagrams - it DOES appear that the head tube determines the steering axis. That being the case, forks with NO rake should provide more trail than raked forks and handle more stably. Is this correct?

If so, then does anyone make forks with REVERSE rake? That should also increase trail, yes?