| All the cylinders are 19mm. It's the ratio that changes. Either x16, x18 or x20.
I run a x20 and reckon it's a little too much, IMO, a x18 would be better as it'd give more feel.
Probably for "just track" a x20 would be ok as the concentration will be there 100%, if I had to grab a handful on the road I reckon there's a chance i'd be off........ | 
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