Neil":3oddw41q said:As others have said, there's many varieties of them, many not triple butted.
If no obvious stamp, weighing would be a good indicator.
I've got about 3 P2 forks, including one of those hateful ones with suspension corrected thing at the bottom of the steerer, rather than in the blade length.
I have a pair I'd love to thread, because they're pretty useless to me threadless (just a bit too short, but would probably be about perfect threaded), but the thread cutting tools are yay-much, and I do wonder whether many LBSs would be up to it?
Cutting a brand new thread on a steerer with forks attached is something that is very difficult. One good method is using a large pillar drill, not often available to most, insert the steerer tube from underneath the table, clamp steerer tube in a machine vice with V jaws then, with the drill chuck removed, use the flat face of the spindle nose to keep the die square, still not easy though.
Ideally one would be able to clamp the steerer in a lathe chuck, clock the steerer and then screw cut the thread, however I've only ever seen and used one lathe big enough to take a set of fork blades up it's spindle, and that was nearly 80 years old and had no screw cutting facility!