Author Topic: Boring/Sleeving a stock master  (Read 887 times)

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Offline camelman

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Boring/Sleeving a stock master
« on: December 25, 2011, 08:51:41 AM »
Okay, I want more braking force, but I want to retain the stock look on my 350f. I've installed stainless lines with a result of an incredibly stiff brake lever. Full braking force only moves the lever about half an inch at the tip, but takes all my hand strength and all four fingers. I was thinking about Sleeving the master to a smaller bore and turning a new brake piston. My goal is to decrease the swept volume in exchange for higher pressure. I'm hoping for an end result of only needing two fingers to actuate full braking force without allowing excessive travel of the brake lever (I could accept another half inch of lever travel). Does anyone have any experience or thoughts on this?

Camelman
1972 350f rider: sold
1972 350f/466f cafe: for sale
1977 CB400f cafe:sold
1975 CB400f rider: sold
1970 CB750 K0 complete bike: sold
2005 Triumph Sprint ST 1050 rider

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Offline verslagen1

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Re: Boring/Sleeving a stock master
« Reply #1 on: December 25, 2011, 09:36:41 AM »
you need to make the caliper side bigger or the master smaller to get more force at the pad.
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Offline grcamna2

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Re: Boring/Sleeving a stock master
« Reply #2 on: December 25, 2011, 11:30:21 AM »
I think that is a good idea camelman & I think it's possible to sleeve it down to 11mm and use a MC piston that is already made for another model; I look forward to your project build ! Merry Christmas.
75' CB400F/'bunch o' parts' & 81' CB125S modded to a 'CB200S'
  I love the small ones too !
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Offline crazypj

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Re: Boring/Sleeving a stock master
« Reply #3 on: December 25, 2011, 11:36:24 AM »
I guess shrinking in a stainless sleeve would be best way to go? (or brass tube as it's easier to machine  ;D)
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Offline dave500

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Re: Boring/Sleeving a stock master
« Reply #4 on: December 25, 2011, 12:09:57 PM »
i had one sleeved with brass back to standard,wasnt very expensive.