Trike 320 rear fork large gap fixed

I posted about this problem:

• Trike 320 frame rear fork large gap — June 13, 2024

The rear fork is this part shown in black:

Thanks to you guys who gave feedback about bending the fork closer. The wheel hub is 135mm, which is a common standard for bicycle rear wheels. However, the fork spacing is 140mm and is too stiff to pull in completely.

At the workshop I attend, received help from Terry, who is a retired school metalwork teacher. We set the fork into a clamp:

Terry advised to do the bend cold, not to heat the fork, so that's what we did.

At the back, we placed an anvil, on which to rest the other end of the fork. The clamp is used by the woodworking guys. I suppose that an ordinary large g-clamp could be used ...hmmm, maybe not, as some considerable force is required. We lubricated the clamp thread to help.

The thing is to clamp to a certain point, where upon release the fork and it springs back just a couple of millimeters closer than the original 140mm. We were very careful about this, clamping the fork, then releasing, then clamp a bit more, and so on.

Very interesting; it kept springing back to 140mm. But a point is reached where the frame will just start to deform. For us, it was when we clamped the fork to 110mm spacing, then released and it bounced back to 138mm.

138mm, that is perfect. Now, can tighten the skewer knob a little, then flip the quick-release lever and the fork is now properly gripping the wheel hub. This is good news.    

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