Hi, I haven't posted on Cyclechat for ages, but am in need of some advice. I was advised to fit a longer stem to my bike after a bike fit at my lbs. The stem they sold me was a Giant contact but had a larger diameter than my aluminium steerer tube, so they fitted a steerer tube shim to reduce the inner diameter. Now, a few months on I am experimenting with dropping the bars a couple of spacers. Only issue is that the spacers on top have a smaller outer diameter than the stem that they sit on top of. Is this likely to be a problem and is it safe to ride with? Picture attached.