Will 1974 Yamaha 650 fork tubes fit on my 1972 XS-2 ?

[battlecat]

I have been fairly desperate to find replacement fork tubes for my 1972 XS-2 (they are badly rusted) so tonight I found what I thought was a really good deal on a pair of fork tubes (complete inner/outer tubes in good condition) on Ebay. The seller stated "if I recall correctly they came off a 1973" so I did some research and found that 1973 TX650 tubes would fit on my XS-2 (they would just have a couple extra ears on the left side fork leg, presumably for a double-disc brake setup - by the way, why did Yamaha include extra ears on the left fork leg for an extra disc brake in 1973 when they didn't offer a dual-disc system until 1974??). Anyway, I compared pictures of the 1973 TX 650 fork legs with the ones that they guy was selling on Ebay and they looked the same - so I bought them. Afterward, I discovered that the 1973 TX650 had external fork caps while the ones I bought had those recessed ones (which means they are probably 1974 fork legs, right??). On further research I find that the tubes are 34mm on the '72, '73 and '74. My question is this...if they ARE 1974 fork legs, can I still use them on my XS-2 (and be able to bolt on the XS-2 fender, brake caliper, etc.??).  I understand (now) that the triple trees for the 1974 are different (in that they went to a "pinch bolt triple tree with internal cap bolts on the tubes" design rather than the external bolt-cap design of the XS-2).
Could I possibly just switch the cap bolts from the XS-2 to the '74 tubes and use them?

By the way, here's the link to the Ebay listing so you can see pictures of the ones I bought:

www.ebay.com/itm/Yamaha-650-xs-fork-tubes-these-forks-look-great-Just-Polished-/271596368868?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2047675.l2557&nma=true&si=p2eDkqWLrhVXpSWkuDSDZJhoT2c%253D&orig_cvip=true&rt=nc

[randeman5]

I am working on a '72 also and have a similar question. I want to change the inner tube out because of excess rust. Up to what years did they provide this tube?

[richard]

If that cap will thread in to your new 34mm forks I don't see any reason why you could not swap the forks, so long as they are both 34mm forks and the thread on the fork tubes match. If you are in doubt you could look up the part number for the fork tubes on both sets and they might be the same, in which case it's a slam dunk