What is this book?

Can anybody please help me remember the name of this book, it's driving me mad.

I read it in the 80s, was written and based in the 70s

Girls meets unsuitable boyfriend, he has a motorbike (or a friend has one)

She gets a much longed for Aubrey Beardsley mirror for her birthday

Boyfriend has crash on bike

It was teen fiction (obviously)

That is all I can remember right now

can't remember, but I know I read it too.

She had older brother and younger one too - her dad was an actor in some TV series.  She had a party, that got gatecrashed.  It was boyfriend that had the motorbike.  He also took her to a pub - he wanted to go in the bar, she wanted to go in the lounge. 

Thank you! That has made me remember it was a class thing which made him unsuitable wasn't it not so much the motorbike. It's driving me mad!

yes, she was a bit obsessed with Nancy Mitford (?)'s U and non-U.

I'm sure the title is "my" then two words and there is an L either in the title or authors name. I can picture the cover and see the shapes of the words!

Try Booksleuth: http://www.abebooks.com/docs/Community/BookSleuth/ 

You can view the US forum without registering but you'll need to register to view the UK site. V. useful.

Thanks CDL have posted over there.

<< sticks hand in air >>

I know, I know!

It's "My Darling Villain" by Lynne Reid Banks

oh you star Cleo, that was bugging me all night!  I thought it might be Lynne Reid Banks, but couldn't find it on her website, so discounted her.

Damn, Cleo beat me to it yes, "My Darling Villain", with the Laura Ashley dress for her birthday and the unsuitable pop concert. 

Thank you all! I was actually sat in the ballet waiting room this morning and the word "villain" popped into my head. I went to google "my lovely villain" and found myself typing "My darling villain". Funnily enough I am reading L shaped room again so I should have made the connection. It is mentioned in the foreword of the book but it's covered by the library sticker!

Off to see if I can buy it now!