Frame trueness.


First class butcher.
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I noticed the right hand VM carb was closer to the frame centre downtube than on the right, it's about 3mm out, so I investigated. I removed the front, rear and top engine mounts, just leaving the long through bolt at the bottom of the frame holding the motor in place, the driven and drive sprockets line up nicely, but the right hand carb is closer to the centre downtube than the left hand carb. they fit alright, the right hand carb is around 1-2mm off the downtube, whereas the left carb is around 3-4mm off the downtube. You'd probably never notice it with BS carbs, but as I am running longer manifolds it places the carbs either side of the downtube.

I considered that perhaps the bike had taken a shunt at some time, perhaps putting a bend or twist in the frame, but discarded that theory as nothing else is out of alignment including the drive and driven sprocket and the steering head which I measured for alignment when I had the frame stripped.

So it appears the lower right side through bolt mount has been placed a little further back than the right.

Has anyone else noticed this discrepancy?