Does the manual have a diagram that shows where the lever on the engine should be?  Earlier model DT175's had a minimum distance with clutch fully pulled.  Later was easier with a pointer you line up with a nub on the case when freeplay is taken up. 

Important thing here is the lever MUST be close to the correct angle or the clutch won't work right...  it won't disengage properly.  That's the primary thing you need to pay attention to.  This is handled by the internal "adjustment" like have the correct internal pushrod parts and then fine tuning by raising and lowering the lever with the adjuster.  It's all about the leverage and the lever travel.  If you start installing longer pushrods or something the lever angle can get out of whack and clutch will always drag even when lever fully pulled.

I'm wondering if someone monkeyed or swapped the cable to try to get free play?  Correct new cable would be my first thought OR you can sometimes make a slotted spacer OR you can remove an inner cable end and solder a new one on.

 

Here's a part of the procedure in the DT175 manual which yours is likely closest too...  manual will have some kind of procedure to make sure lever is in the right place. 

 


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Doesn't it move the arm back if you "lift it up", no free play--to --too much must be a clue there. Or am i back to front. I'll read back on post & update later.

I wouldn't get too worried about aligning the arm with pointer if the cable is out of adjustment, just adjust your eccentric up till the arm is back far enough its to take up the play--sort of.
I just looked back at Marks & different views & not saying i'm wright, but never mind i've written it now---standing in the naughty corner lol.

I found out the hard way if the arm angle isn't within the "sweet spot" range freeplay can be correct and everything looks great but clutch will always drag.  It doesn't have to be perfect, just somewhat close or the "throw" ends up just a bit short.

Yamaha put that info in the manuals for a reason I guess.