Hi Mark,
Several owners have reported similar experiences with mixed f to r tyres. Doesn't seem to matter which brands you mix, the results seem constant, ie the rear feels to be loose.
When I bought mine I had Yoko front and B'stone rears. Front stuck like glue in dry was useless in wet. Rear just struggled to keep up!
IIRC, Monaco92 had B'stone fronts and F1 rears and had same issues as yourself. Tyres went back to Goodyear for check and were given the all clear. Suggestion was to switch the fronts to F1's but in fact he went to B'stones on rears as fronts were still good and is now happy
HTH and keep it safe
regards, Paul
Senninha
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