That's not too good
If you reve the outer sheave and belt, everything that COULD vibrate is the inner sheave of the driver and the engine itself..
since the driver inner sheave is rather weightless compared to the rest of the moving mass...
well.... the engine is more likely to cause that.
Still to be sure, remove the whole driver assembly to to test again.
But if it's the engine (which of course is vibrating a bit when running) but "a bit" and for sure not more than with a cent clutch installed,
you're basically out of luck..
I notice a minor thing on your weights (or better the springs)
unhook both garter springs then close then back together and snap them back onto the weights;
this time make sure that the hooked ends are exactly 180° apart (one sitting exactly in the center of one of the two weights, the other one in the center of the other weight)
It'll make a very small difference (barely noticeable) but that's how it's supposed to be.
Other than that the weights look good.
The fixed sheave of the driven (the one you point to) should NOT wobble.. not at all!
if it does it could cause vibration.. but NOT at idle (when it's not turning) of course.
So for now we can rule that out
I assume that's the belt that came with the unit, right?
(odd markings... hard to ID it...)
Are you sure it's orientated correctly (flat side goes towards the engine, bevelled side points away from the engine)?
(no, I'm just curious

)
Hm, if you cannot get into high ratio with the TAVKit, it might be the engine not having the power needed to do so...
your weight is already within my calculations above (121 lbs the bike.. 150 you.. some fuel... 275 lbs..)
I said, that my calculation is conservative (asking for 5.1:1 instead of the 5.0:1 you have as a gear ratio)
but I expected 6.5hp from the 196cc engine...
the manual states 5.2 horses only... (11Nm instead of 12.6 of torque)
sorry, haven't rechecked that.
So according to my calc you'd need 5.5:1
conveniently you can get past that with just a 9T TC sprocket (as opposed to the 10T you have)
http://www.ebay.com/itm/9T-40-41-Sp...orque-Converter-Driven-TAV2-NEW-/221282516274
Sorry for the inconvenience...
that'd bring you down to 5.56:1 and you should be able to hit ~40mph
you could also change the rear wheel sprocket if you prefere (55 or 56 teeth)
to do the same.
that should provide the ratio needed to allow the engine to fully rev up.
(frankly.. 5:1 should be hard on the belt.. but still work)
So maybe there is something wrong with the engine.. either it doesn't have it's full potential for some reason (carb clogged or unadjusted... compression loss.. foul plug.. IDK)
or your throttle cable doesn't open the butterfly all the way (pinched cable, too much slack *shrugs*)
I'd say get the spark plug out and check it's colour.
(should be light tan.. fancy speaking "latte macchiato"..)
much lighter and you need more fuel, darker and you have too much fuel in the mix.
If that's reasonable in color with the engine off, remove the air filter (so that you can see the butterfly moving)
twist the throttle all the way... and then see if you can open the butterfly even more manually... if so, readjust your throttle cable.
None of that costs any money (nor is very time consuming either)
So I'd check that first before I'd buy a new sprocket.
If it still doesn't rev up under load you can still order a sprocket knowing the engine is perfectly okay.
When in doubt, post pics (or a video might even be better here)
And we'll be helping you with a few sets of trained or at least well rested eyes
'sid