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Home of  my Yamaha RD400  Drag racer.

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Ora et Labora

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Detailed shots of how TZR swingarm and sub frame are fitted.

First Attempt Finished.

Second Attempt at Frame

So after sitting back and looking at the frame it was decided that we hadn't got the steering head angle correct. It looked good but didn't measure up correctly. Basically we had way too much rake. So it was back to the drawing board. By putting the forks back in the jig and holding them at 37 degrees we could see how far above the frame the steering head had to be.
The 37 degree angle was a number that I had seen on other larger drag bikes. So I thought I would try that angle of rake. We then made up frame tubes to fix the steering head in that position. Solid plugs were turned from bar and fitted into the cut ends of the frame tubes. This made sure that the old and new tubes joints were as strong as they could be.

This is how it ended up……………The front is sitting a bit low in this pic. But once the front tire is on and the forks lifted a bit in the triple clamps it all looks fine.

After I had finished this project I learnt that I should have shortened the fork leg action. So that they only had about 1.5 inches of travel.
This would have also meant that I probably would not have had to move the steering head up so far. I might have got away with just raking it out and not moving it up at all.
It explains why, although the numbers were correct, the frame around the steering head just didn't look right. But time will tell when it comes to how well it handles.
NOT BAD FOR A FIRST ATTEMPT AT THIS CAPER.