I got it from a dutch motorparts webshop.
First i wanted to make one myself.
But when i was shopping for a brakeline it came across.
When you got air in the system it compresses and you loose the firm feel.
And if you only use one finger i think it is just enough to let you think you miss power in the brake.
What also helps is the extra spring under the plunger that keeps the pedal up.
Without it the pedal was not coming completly back up.
So everytime you pull the LHRB it first lifts the footpedal up before the braking starts.
And the extra pull you had to make was quite noticeable.
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