Got the new master cylinder installed. After talking with Mike "Mercury" Morse of 650Central/Vintage Brake fame, he suggested a 13 or 14mm master cylinder.
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Oh yeah....notice anything missing in that pic? Turns out the kill switch was disconnected for a reason. The plastic on the back of the on/off/on knob has been damaged and it won't hold the little metal piece in place anymore. Tried to repair it, but it looks like I'll be replacing the RH controls instead.
I STILL have a spongy lever, though.
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I think it may be the bleeder screws. They're in HORRIBLE shape and seem to get wet as the bike sits. I have a feeling that they're letting a little air bleed by. I've bled nearly two whole bottles of fluid through the system and I still get some VERY tiny, foamy looking bubbles from time to time, as well and a soft lever.
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Called my Honda dealer and ordered two new, genuine Honda bleeders. $10 bucks a pop! Ouch!