matt on 05 Aug, 2018 09:20 PM
That is a really wide scale - you're taking a map that is natively 1:24k and printing it at almost 1:200k. Short of zooming in and covering less area per page, there may be no way to get a readable resolution out of the map.
That said, you're also looking at a JPEG image, which applies some JPEG compression to reduce the size. If you set the format at the top left of the print page to PDF, or replace the i with a p in the URL (https://caltopo.com/p/0431), it will give you a PDF that doesn't have the compression applied and should look a little sharper.