Yes - most chains are 115 links and need to be trimmed based on Crank and Cassette,
Ours is 118 links - so with the normal Shimano system 52/36 and 11/23 cassette - I usually trim 5 or 6 links. In sync mode you will never get into the big front ring and largest rear cassette so you can trim the extra link if you like.
When in the big front and large gear - the pulley can be almost at its full forward position. Not taught but almost to the end of its forward travel. More to your concern - There are three holes where the Shimano tension spring could be inserted. Low, medium and high tension. If you bounce the bike on the two wheels and the chain is so loose it can come off - you can change which hole the tension spring inserts into and it will fix that issue.
With the over size pulley system you need to measure.
Dan Kennison
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