Should I prune my grapes now?

I have grape vines,some planted ,others self seeded,setting fruit now.
Last year I got no grapes whatsoever so over the winter I pruned them hard and train them up to my fence lines. So now they are growing well but there's  lots of new foilage that doesn't have fruit on it.
Thus far,I've been twist tying these along side of the already trained vines.
I have been thinking that pruning off these new tendrils would direct energy into the fruit,allow air flow to discourage disease, and supply me with  cuttings that could be propagated.
Are these reasons  sound?

The vines are definitely in the way,so if they shouldn't be strapped to one another(I'm afraid it will promote fungal disease), and pruning has no other benefits ,I will build more infrastructure to train them to.

How old are the canes? Are you out of frost risk reliably? I am no master, but this is what I have done at a friend's vineyard in the Willamette Valley helping intermittently over ten years. During dormancy cut back to 3-4 main canes. After frost risk has passed, you want to choose two main canes off the central stem which will become the trunk. If you are worried about a random frost leave a couple more as backups. Train these two stems to the head wire. You can do this many ways but its how I've done it and it works. Thin around the clusters to allow sun to hit the grapes themselves, as the heat increases brix and complexity of flavor (they don't photosynthesize), and the airflow mitigates mold pressure.

Self-seeded are likely to be male from what I have read. It's something like a 7:1 ratio. Could be at least part of the issue.

Sounds like I will be pruning my vines.
I'm going to try rooting the cuttings, short +/- 10" shoots,rooting compound, self wattering bucket full of Pro Mix, opaque plastic bag.
Cheap expiriment,could make tons of viable vines.

I wonder, are many separate vines,prunned short, better than one sprawling vine?
They are clones,mostly, so resilience isn't going to be much improved.
The one vine is amidst black raspberries,mulberries,comfrey,onions,hardy kiwi and such,a haphazard guild of sorts.

Vines are big here in France but then so is wine
A lot depends on what you want to get from your vines , vines can grow big and I see a lot of vines growing wild in the country side as well as in my garden . The crop is not great and difficult to reach often . Not sure about the male vs female comments as I have never seen a male only plant they all seem to have grapes of verious sizes .
If you put the effort in you can get a great crop but as descibed above you have to put a lot of effort into removing what the French call bleeders , side shoots that put on vegetation rather then fruit and concentrate on just a few shoots .

David

Hello William, I can recommend you this grape vine pruning guide  with useful illustrations. Once you understand the vine pruning principles it should not be a problem anymore. Good luck.
Have a nice day,
Peter Sabo