HT2 crank side to side freeplay.
 

However, cycling/shifting etc is ok, only realized it after I used SPD pedals for a week and I used my right leg to move the crank.. What could be the issue? Loose preload cap/bolt? Or do I need spacers?

Is this a double or triple crank? The triples come with a non-drive side spacer while the doubles don't need one.

For a double, loosen the nds arm's pinch bolts, tap the driveside crank arm a few times with the palm of your hand to be sure it's completely seated in the bearings, snug up the pre-load cap then tighten the pinch bolts to the torque spec. If you have a triple, be sure the spacer is installed then do as above for a double.

Its a double piece crank, I'm pretty sure the shop that installed for me added a spacer because my spindle wasn't long enough? I'm not too sure why though.

By the way, given that I just discovered this today after the installation in March, I hope I haven't done any damage to the BB ?

I've had this problem. It arises when the stacking up of tolerances works out to be not in your favor. A 68mm wide bottom bracket shell may have a range 67.5 to 68.5mm wide at manufacture & be considered within tolerance...but is that with or with out paint? A bike of poor quality control may rely on dishonest methods (paint), ignoring worn out measuring tools & ignoring dull facing tools to simply get the frame out of the factory door. Sometimes even reputable manufacturers have this problem. Think of the ancient & worn-out Sturmey-Archer in the end times just before SunRace rescued them & invested in all new tooling.

The crankset can have similar variation to be good from 67.5-68.5mm for a road crankset or 71.5 to73.5mm for a mountain crankset.

Then factor in the spacers required for a mountain crankset in a road frame. The 2.5mm spacers could have a range from 2.4 to 2.6mm each, for example. Times that by 2 spacers.

Add it all up: A 73.5mm wide crankset, minus a 2.4 spacer, minus another 2.4 spacer, minus a 67.5 wide bottom bracket shell that is now missing some paint equals at least 1.2mm of gap that must be taken up with "something" That may or may not be with in the range of the bearing preload cap. In this case, it would seem not.

A Wheels Manufacturing FW-1.0 spacer between the bearing cup & the bottom bracket shell is probably the solution to get back with in the range of the bearing preload cap.

Parts variation is not unique to Hollowtech either. I've also had to exploit this variation with Dub bottom brackets in Bushnell eccentrics (2 of 2, so far :troll: ) & had the opposite problem with a brand new GXP bottom bracket with an "super old" GXP crankset. The vintage Raleigh they going in measured perfect.

No 2 installations are identical & the manufacturers do the best they can to economically stay with in industry "standards." It's actually quite very difficult in manufacturing for a factory to be consistent even among itself.

Sometimes you just get an unfortunate combination of components.

All HTII cranks are two pieces. What I was asking is does it have two (a double) or three (a triple) chainrings?

If the spindle is too short, why would a spacer help? Perhaps that's the problem and the nds crank arm isn't going on far enough to clamp firmly. I think a return trip to the shop is in order and find a different mechanic.