If you don't have a decent chunk of frame to act as a heatsink for the reg/rect then you really ought to get a plate on it, or buy one with fins. Sticking it in some airflow is also gonna help. They have to dissipate all the excess voltage / current generated when your engine is spinning at high revs, and if there's nothing to take that heat away, they fry.
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MC21SP Plaything
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