Hi, i picked up a set of carbon wheels about two years back and after having some trouble mounting them, i busted out a measuring tape and it looks like they actually are 135mm stadnard and not 142mm. They were through a third-party seller and not well marked, but i confirmed with Reynolds (via the serial number) that they are not counterfeit.
is it possible / worth it to get the hub rebuilt for a 142mm standard? or is juice not worth the squeeze?
You mean they are 135mm thru axel? They are like 10 years old?
I think your best bet would be new hub end caps if they are available for that hub.
Either they are 135mm thru-axel or they are defective. Because they appear to have their end caps (or rather, the end-caps for the model tha corresponds to the serial number do not fit) but they measure around 135mm.
To the best of my knowledge, 135mm is the regular MTB axle that was for open dropouts.
142mm is true thru axle that was essentially the “same size”, but used the closed dropouts.
In a typical case, you just need to swap hub end caps and the related quick release / thru axle.