With 4 x1" holes in the lid running stock pipes 130m/j is normaly enough. If your running race cans on stock pipes run 132m/j.

Lowering wise, as Fontyyy says. Best lift the rear. Look in the workshop and you will find a drawing of the HRC linkages. Make a pair of these and this will lift the rear almost a full inch.
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If I have to take the carbs off once more...