Obviously there are tons of theories as to what causes those issues, but in this case the lever difference in the MT420 seems to have cleared them up. I recently wrote about the Hayes Dominion T2 brakes, and they compare favorably to the MT420s.
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Cues Range: Cues BR-U8020. Deore range: Deore BR-M6120. Deore XT range: Deore XT BR-M8120, Deore XT BR-M8020. Saint range: Saint BR-M820, Saint BR-M810. Shimano range: BR-MT520, BR-MT420. SLX range: SLX BR-M7120.
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D03S RESIN BR-M8120,BR-M7120, BR-M8020, BR-M820, BR-M810, BR-M810, BR-M640, BR-M520, BR-MT420, BR-M820, BR-M640, BR-M9120, XTR, XT, SLX, SAINT, ZEE, ALL 4 PISTON CALIPER SHIMANO DISC BRAKES. Shimano Saint.
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Shimano BL-MT401 / BR-MT420 Vorderrad Scheibenbremse 850 mm MT400 MT401 MT420. Modell: BL-MT401 + BR-MT420. Das Symbol der durchgekreuzten Mülltonne bedeutet, dass die Batterie nicht in den Hausmüll gegeben werden darf.
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perfect unused condition. purchased for a bike build which didn't happen.. ready to fit sensible offers accepted
eBay
Cues Range: Cues BR-U8020. Deore range: Deore BR-M6120. Deore XT range: Deore XT BR-M8120, Deore XT BR-M8020. Saint range: Saint BR-M820, Saint BR-M810. Shimano range: BR-MT520, BR-MT420. SLX range: SLX BR-M7120.
eBay
Cues Range: Cues BR-U8020. Deore range: Deore BR-M6120. Deore XT range: Deore XT BR-M8120, Deore XT BR-M8020. Saint range: Saint BR-M820, Saint BR-M810. Shimano range: BR-MT520, BR-MT420. SLX range: SLX BR-M7120.
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1750mm Rear Hose. Funnel bleeding. Shimano Disc Brake Set. Supplied as "J-Kit" - Part Assembled, Ideal for Internal Routing. Shimano Part Code Lever: BL-MT401 (2-Finger Lever). Shimano Part Code Rear Caliper: BR-MT410 (2-Piston).
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