Was ratting round in my spares shelves/boxes. Found a 3-bolt tappet cover with slots instead of bolt holes – wtf?

Then found three more

Ah so! Early XS1 covers. No O-ring grooves. Gasket pure.

 

tappet covers, outside … early 3-bolt, slotted, gasket, … 4-bolt decompression cover, XS2, holes, gasket … 3- and 4-bolt cover, holes, gasket … 3- and 4-bolt covers with holes and an o-ring groove cut – 1 set alu, 1 set chromed

 

 

tapppet covers inside … here you can see the flat gasket faces and the grooved o-ring covers

 

 

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