John, yours should have six leaves and 3/8" U bolts.
I'll measure up shortly and post the numbers.
Before the change I could fit two fingers between the top of the rear wheel, and tyre. Now it's 4 fingers. Roadster tyres are low profile compared to Bumble's 70 profile so that will make a difference.

Roadster: N/S 22.8cm. O/S 21.6cm.

DaveW
'05 Red Roadster S1
'16 Yellow (Not the only) Narrow AR GDI Plus 4