The fist thing to do is shift (off the bike, carefully and at low speed) into the big/big combination and see if the chain is long enough to loop it with at least an inch to spare. Do this very carefully because if it does shift, and the chain is too short, you'll bend the axle, so gently ease into the shift.
If the chain passes this test, it's long enough, if it doesn't do not ride the bike until you correctly size the chain.
Another factor is the height of the RD upper pulley. The larger sprockets may require that you push the RD down. This is done either with the B-screw on the upper body (pre-2001) or with the worm gear screw between the lower body and cage.
The rest is basic textbook adjustments.
__________________
FB
Chain-L site
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