J. A. Holland / Nervex lugs seatpost help?

[Marcho]

Trying to fit a seatpost to my J. A. Holland - the seatpost cluster has funny dimensions. On one axis it is 26.6mm and the other (rotated 90 degrees) is 25.6mm. The lugs are nervex and there is no obvious damage, but I am concerned that only part of the seatpost will be in contact with the seat-tube when tightened. I have a range of Reynolds (R3 and R5) and Strata posts and all of them are too big!

Can anyone tell me the internal dimensions of their identical Nervex seatclamp clusters? Hopefully I can tell if mine is 'right' or not. Many thanks.

 

[keithglos]

I think you have plain tubing, and the seat lug has been tightened on to an old alloy pillar. If you can check that the tube below the lug is not so distorted, then open up the slot in the seat lug a little. The aim is to reshape the lug.
The bolt will pull in any small distortion.