Need help identifying this Yamaha Monoshock!

[crossedup2]

I'm not sure if it came off a dirt bike. Last time I had my 125X shock serviced at Chivo's in Sydney he made the comment that these shocks were the same as the TZ750 around the same period. The differences he commented on was the size of the shock. (length? dia? not sure what he meant by that). That may also account for the thinner spring wire and two stage spring??

It's more than possible that you pick one of these up....

Regards
PB

[Nathan S]

I'll try to take some close up photos of that area and post them later..

So - next question...  Would that shock be legal on a YZ250 or 360B?  Not that I own one, just curious.  It would appear to be a period modification.  Or would the actual kit type need to be identified to see if it would have been available to YZ-B owners pre-75?   

In pre-78: Yes.
In pre-75: No, because it exceeds the limit of 4" of rear travel.

While there's lot of 'maybes' in the way people interpret the rules, rear shocks are pretty easy - keep the travel within the era's limits, and don't add remote cannisters and you can do pretty much anythine else.

[IT400C]

Looks like an aftermarket kit after all.  If you look closely at these photos, you can almost make out where the threaded section butts up to the chromed shaft.  I think you can even see the remains of some red Loctite.  (from memory red Loctite is the stronger stud lock - for things that you won't be removing regularly)