Duncan, the 1200 is an in line E/W 4 cyl. 98 only, but if I was stuck I`d use what ever`s available. Yours being the boxer may take a lesser octane, have to check your book for that one ....
Interesting , I have an X5 4.4 V8 petrol, that, by the book will be ok with any of fuels. Go figure! So it gets the odd tank of premium but makes no difference with the engine power , as it still goes like .........k