Well it's quite amazing how every step forward with my CT3 always fights me.
I picked up a set of front forks and wheels some time ago for this bike .
The legs had been reground and new seals and oil put in but not by me.
The forks were dirt cheap and i thought the guy didn't know how much they were worth or just wanted shut of them or something else.
When i fitted them my question was answered. one leg was longer than the other by 10 - 15 mm
So this problem just needed a coat of looking at .
I drained the oil, clean but only had 55 ccs in it . Mmmm that's not right. What's the other like?
Same .
Both clean inside so i stripped the longer one.
I had a feeling that it had either been assembled wrong or it was a stanchion off something else.
Jacked the bike up and removed the wheel . Nearly broke my fingers and actually cut the top of my hand because unexpectedly ,the allan bolt that holds the stanchion to the lower outer undid and was barely nipped up and as you know, normally you need a firm turn to move them.
I knew there and then what the problem was.
The small bullet shaped securing device wasn't located proper.
Sure enough that was it.
So, if you build up the forks on your bike and you get the " one leg longer than the other" problem, that's where to look. It fits on the bottom of the damper rod after you've located the rod into the fork leg. It fits inside a recess inside the bottom of the fork outer tube on both aluminium and steel legs. It's the bit at the bottom of part 6 in the Yamaha fork diagrams for the CTs, which the bottom bolt and copper washer attach to.

Yes, I've seen those damaged too by someone assembling wrong and tightening the bolt. Can be difficult to find replacements.

Yeah one leg longer that the other can be a problem, better be carful, you could end up going in circles.

If that bike ends up being able to go round in circles ,i'll show my ass on top of Winter Hill

Don't get corrupted Dave, it's arse over here! Unless, of course, you're talking about taking a pet up there!

Well funny you should say that as i swapped my Donkey for 2 ton of 7076 Aluminum

Noooooo........ You really have gone to The Dark Side! Talking of which, have you seen/heard the Darth Vader clips with Dave Prowse's voice, before they were overdubbed by James Earl Jones? And whilst I'm off on a tangent, the Night Rider's voice in the cinema release of Mad Max is also overdubbed.

Was going to guess that one topping out spring is missing but doesn't look like they have one. If you disassemble both are the fork tubes different lengths. If not then compare dampers & item Number 6.
www.partzilla.com/catalog/yamaha/motorcycle/1973/ct3/front-fork

RT325, stop joking us, get serious,