Exchange 2013 Mailbox folder

You need to backup the Exchange mailbox database, this will replay the content of the logs into the main database and them remove them, once the backup finishes.

check this link please

http://woshub.com/how-to-move-and-truncate-logs-in-exchange-2013/

all the best

As you dont have backup solution
Refer to this link to use windows server backup
https://technet.microsoft.com/en-us/library/dd876854(v=exchg.150).aspx

Circular  logging wont work fine to you and will effect performance
And as it just delete old log file to keep on certain size
You can use windows backup to reduce the edb log size and have a backup of ur mailboxes

The  logs are not  big there are just lots of small ones. can I delete them ?

Its small size by design exchange 2010 log file is 5 mb
Exchange 2013...2016 1mb

Ok Will delete  some of old one see how I get on

Do not manually delete transaction logs. You cause cause the database become usable will will not be mountable again.

Exchange Logs are only needed to recover mail if the database becomes corrupt. Logs files are committed to the database immidiately. In some cases there may be .chk files in the logs which means up until the .chk log all of the logs have been successfully committed to the database. Anything else after would still need to be committed.

This is typical if you have a database crash and logs were trying to be committed during this failure.

Will.

You can view checkpoint information using the ESEUTIL /ml <log file> and see the checkpoint information, if unsure which logs are safe to delete.

Delete the old files and the exchange is fine.