I think if you make the forum the main page you will be ok and if you have not received a warning from google in webmaster tools then I am not sure this is the issue. I have not looked at your site but if your archive is off and you have the forum as your main page I believe you will be ok in terms of the mobile.
Again, there is a huge refresh going on and Google has changed many ranking factors. It could be mobile as this has become a major ranking factor but it could also be many other things.
It is good you are fixing this but check out webmaster tools to make sure you are all set with everything else as well. Once you fix these things you may have to wait for the next refresh to see any ranking go up if this was indeed due to ranking.
Check Bing webmaster tools as well. many, many webmasters over look this and miss out on tons of traffic from Bing.
09-03-2015, 07:32 AM
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