I’ve played with a few different Bringheli frame jigs, and recently purchased one of my own. One thing that has always vexed me while looking at them was to figure out how to align the different bits and pieces. With no markings at all on the jig, setup can be a bit of a challenge. Dave Anderson covered almost all of it in a post he has on his website. I’ve borrowed and stolen his methods to do setup on my jig in much the same way.
One thing that I couldent find anything about was how to make sure the rear end is aligned with the bottom bracket properly. Every Bringheli I’ve played with has used a different mechanism to hold the BB shell, but they all move freely and are infinitely adjustable. With no markings it’s not to hard to infinitely adjust yourself into trouble. Here’s the process I used to align my jig.
First. Measure from the support boom to the middle of your rear axle (213 on mine, but I’d double check yours).
Measure from the backplate to the center of the rear axle.
Then, measure the total width of your bb holding situation, with a shell in it. Remember that not all shells are created equal, so this isn’t a one time thing. Divide this number in half.
Measure the total width of your bottom bracket holding situation.
Set the outside of your innermost cone to the first measurement – 1/2 the second one. So on mine it’s 213 – (125/2). This gives you the distance from the support boom to the outside edge of your inner bb cone.
Measure from the support boom to the outside of your BB shell holder.
As a bonus, you can do the same thing with your seat tube cone now that you know the size of your bb holding assembly. That measurement is what you got above (boom to outside edge) + 1/2 the width of the whole assembly. Remever to account for the thickness of the various supports off the jig (seat tube runner thing and the thing that supports the cone itself.
It took me longer to write the email than to actually do it.
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