The chain is endless so you will need to join it properly, do not use a split link otherwise it will make a big mess if it lets go!
Make sure you use Hondabond on the jointing faces of the crankcase joints. Don't use silicon RTV. You can buy it on ebay for about £15/tube. Only use a very light smear on the joint face you dont want it squiting out into oilways etc.
If the cases are coming apart it would be a great idea to renew the balance chain at the same time.
