Bending forks

After riding The Postmaster for a few days, I realised that the taking my hands off the bars would result in them veering off to the left by themselves, making it nearly impossible to ride hands free.  I had a quick look at the forks and even eyeballing it they looked a bit crooked.  It sounded like a trip down to the framebuilder to have it realigned.   Although you can't see it in the pictures, the first part involves clamping the steerer in a vice and using a large 2 x 4 wedged on the inside against the crown to bend the forks back into shape.

Each bending is then measured and it's an iterative process, not only do the fork legs have to be straight and centred, the spacing between them has to be correct, and the fork ends have to be parallel, the picture above shows them being made so.

Finally the forks were back in spec and straight within 0.5mm.  I had them measured for trail as I was curious, the rake on the fork as you would imagine was massive at 86mm, this combined with the slack 69º head angle gives a very short 36mm trail which explains the light steering.  As this was intended to be heavily front loaded this makes total sense.  As a comparison, a typical road bike has a head angle of 73º and a rake of 45mm which gives you a 56mm trail.

The handling on The Postmaster is quite different to a typical bike, the long wheelbase, low trail and rear weight bias creates a stable, slow steering bike that has light and responsive steering.  The funny thing about the low trail and front loading is that this is starting to come back in fashion now on Randonneurs and touring bikes.  Seems like nothing is new is it?  Thanks for reading.


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