On a vine that long neglected I'd cut back to the trunk. That will cause many new canes near head of trunk. Save about 4 next spring, 2016, for fruit. You probably won't get any fruit this yr unless there is a cane from last yr very near the trunk that you can save.

Sap running won't hurt anything. Let it drip.

I really appreciate the help - thanks

Is it possible to take cutting also?

Now would be a good time to take dormant cuttings for rooting. I'd take one yr canes of medium size that were well exposed to sun last summer.

Thank you!
I can do that, (no shortage of sun here)

The few grapes were really very good (last year) black and tasty.
But I had inherited a vine that left me with a dilemma of
should I trim last years growth?
or would the vine be benefited by polarding?
or perhaps something in between?
I realize time is running out but I just didn't know how to tackle it.

I don't grow grapes but I would assume that on an arbour in Greece you would be looking to create shade as well as fruit. So wouldn't it be more sensible to prune back to the framework which follows the arbour wires/posts rather than right back to the trunk? It doesn't actually look that neglected as the long growths don't seem much more than one or at most two year's growth. It might be a good idea to try to talk to some local growers who have experience of pruning styles in that part of the world. What do the neighbours vines look like at this time of year?

Indeed
The locals grapes look in great shape.
My friend left this vine in charge of an elderly neighbour, It has grown in his direction over the wall & down the fence towards his balcony.
The newest bit always provided grapes steadily in his direction.
I made enquiries to a local, asking for advice/ assistance & sadly he was under the impression I was flirting with him. (It's a small island & I can't afford such misunderstandings)
The Neighbour died last summer, so I thought there was a small window of opportunity (before spring) to help the vine - but possibly I should leave it.
No good deed goes unpunished.

Please note that grapes as well as Muscadines grow on NEW Wood. That is why you had a few grapes far away from the main Cain. I would cut every thing back leaving only a few canes coming from the main cane. Then any of the canes that are left cut the smaller canes back to only 2-3 buds were the new growth will come from. It will be fine.

Hans

Thank you - I appreciate all advice given.
The locals have great grape vines -they constantly keep them pruned back - so they never need a saw.
This is a case of years of neglect. It has run amok. I see a thick web of old wood latticed.
It is obvious it was once established & pruned.
Now I thought I'd cut out just one branch at least 50 ft long (ending far beyond the abour) & then Prune any lighter stuff above the supporting structure.
& then pick another woody branch to cut back again this time next year.
but that's just because I am a coward.
What I would like to do is cut it back to its basic 'Y' leaving between 2-3ft (one left one right)
I will take cuttings from the far end (of the branch I am removing) -so I can establish another in the future too.
Does that sound ok?

This is the runaway vine (photo taken last June)
It has left the arbour (beyond photo starting at the left behind the building)
It even grows along the fence in the opposite direction behind the olive tree.
it has been 'encouraged' over & along the fence.
Anything in its path was removed from the fence - you might notice a jasmine now on the ground.
This is the newest vine growth - this is where the grapes grew last summer.
It even grows beyond this photo far off to the right.

You might want to check out this video on YouTube.

Hans

Here is a link that might be useful: Neglected Grape Vines

Thank you Hans
I am grateful for the clip it really helps to see how people tackle the problem.
- I was really disheartened at all the grape vine videos that only needed pruning with secateurs.

If only this vine looked like the one in the video!
The first photo above shows wood as thick as the scaffolding poles, certainly the more recent growth along the fence is not as thick - until I take it back to the abour.
It just seems practical to make fewer cuts into the thickest areas -instead of trimming the outer edges & leaving the wooden mass above the arbour (the first photo is shot from above)