I have large amount of home grown beetroot, I have pickled one lot but when we tried it the vinegar was very strong overpowered the taste of the beetroot. I have so much more I want to pickle anyone any advise/help. With the first lot I used Sarsons ready to use pickling vinegar.
Two things: I always pickle beetroot in cider vinegar (you can buy 5l containers not too expensively)
Also, IMO beetroot is much better pickled and used within 2-3 weeks otherwise it gets too pickly as you say. We store our beetroot in boxes of sawdust over the winter & just take it out & cook when we want some - it keeps fine til the spring in the garage (though by Jan or so its a bit soft to grate into salads raw which is the other way we eat it).
I've got that candy stripe beetroot. It's very disappointing stuff. If you boil or roast it, it goes pink. If you slice it thinly it's pretty but there's not much taste there. I'll be donating my seeds next year in favour of some golden ones. I've got lots though - I'll be looking for ways to store it that doesn't involve pickling. It's too pickly for me... I fear I may drown under chutney this year.