I recently bought an OTK axle from an auction site having gone through the due diligence of confirming it was straight and checking to see if it was excessively marked by grub screws (there was no close-up photo in the auction listing). When the axle arrived I found the grub screw marks were plentiful and fairly deep, not only that but once fitted it was clear that the axle was slightly bent. The lesson for today is that people sell axles because they have seen their best days so make sure you visually inspect a used axle. This one went back from whence it came!
I am still unsure about whether budget-bound folk like me should look opt for used OTK or a new Alto axle. I’ll mull that one over for a bit…
I’ve just had to replace the rear axle to because there was a 1mm runout on the left side and 0.5mm runout on the right, it was causing the chain tension to be all over the place. I didn’t think such small runout on the right side would have such an effect on the chain but it turned out to be the combination of the two sides. In trying to fix the issue I tried replacing the chain, both sprockets, sprocket carrier and then I thought the crank was out of alignment so had a bigend rebuild all to no avail. Lastly I thought it must be the axle, I looked for a second hand OTK item first but saw the price for a new pattern part with new bearings was the same as a used OTK axle, so I bought the pattern part, I’ve been very happy with the item and it sorted my chain tension problem to. I have found in the past that it’s always a gamble buying used items.