
I have recently acquired this gorgeous 1975 860 GTS. It's all v original, 21k, instrument binnacle needs sorting as does rubbish wiring, and aside from ripped and worn seat cover, rusted chrome and slightly rusty original rims its all there. 21k miles, which is supported by provenance etc.
I've ultra sonic cleaned the carbs, but despite spark, and the odd pffft.. nothing. Tonight I conducted a compression test tonight and saw 89 rear, 77 front, then with the oil injection trick, 91 front and rear. At this point, turning over the started motor resulted in several bangs from the rear pot and a warm header pipe.
In short, I am guessing possible leaky valves / rings etc? Any thoughts, help much appreciated. Thanks
