Is it possible to change 140mm pikes to 150 or 160 with a new air spring?
I have heard from multiple sources that rockshox use the same chassis for all of the pikes which makes sense.
the only niggling doubt I have is that the travel scale printed on the stanchions only covers 130mm/140mm or 150mm/160mm depending on which fork you have.

To me this suggests 2 possibilities…
1, The stanchions are only long enough for that travel range stated on the side
2, All stanchions are identical but Rockshox only print on the travel ranges most likely to be used.

Obviously I would like the answer to be 2 as this would just mean the markings on the fork would be off which I can live with.

Anybody know for sure?

i thought there were 2 different lengths?

Older 29er forks can only go to 140mm, as far as I know – same air spring part is used for 160mm 27.5 and 140mm 29, newer ones can all do 160 I think

Best way to be sure is to stick your serial number into this site

https://trailhead.rockshox.com/en/

Get your serial number off the back of the crown and enter it in here.

https://trailhead.rockshox.com/en/search/

Should have said forks are 27in…and I haven’t bought them yet – suppose I could ask the seller for the serial number…

27s will go to 160mm. You just need an air spring for either 140mm 29 or 160mm 27.5. Sram tech docs will give you the correct part number. On amazon for £35.

Older 29er forks can only go to 140mm, as far as I know – same air spring part is used for 160mm 27.5 and 140mm 29, newer ones can all do 160 I think

Thats the wrong way around. The Pike A1/2 can go to 160mm in 29″, the new Pike can only go to 150mm in 29″.

I did exactly that, 140 to 160 travel increase. Just changed the airshaft, as you say though you can’t use the printed scale anymore.

In simple English it’s option 2.

If you are buying older (pre-debonaire) forks I would 150% recommend getting the debonair damper.