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Discussion Starter · #1 ·
So one thing that has been bugging me is the fact that my front brake lever (disk brake) has been very wobbly since I got the bike. My brakes work, its just that there is a LOT of play and when I rode the bike, I could hear the brake lever rattling around from the vibration. At first I thought it was that the bolt holding it in place was loose, but that wasn't it. After looking at my service manual, I suspect that it is because the brake needs to be bled since the "button" in the master cylinder does not come in contact with the "finger" that pushes it on the brake lever. Thanks for the advice in advance!
 

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Sounds like your master cylinder is sticking. It may need rebuilt or replaced? It happens to a lot of these old Honda's. Especially when they sit forever with old brake fluid in them, and are'nt used regularly.

Try taking it off, cleaning it out, and refill with new brake fluid. It may loosen up, but probably not.

My two cents..

GB :mrgreen:
 

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could be the pivot hole in the lever is worn oversized, letting the lever flop around
 

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Discussion Starter · #4 ·
Yikes, I really hope I don't have to rebuild, that costs money and my patience haha!
I do not think it is a worn hole issue since the "play" in the lever is rotational rather than translational.

I will try some new brake fluid and I will bleed the brake sometime to see if this fixes the problem.
 

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If it needs rebuilt, then a cheap option would be to use a newer style master from another bike. Ebay is full of them from various models. Since I'm going with dual disc front brakes, I sourced one from a GSXR1000. You could do the same except you could source one from just about anything that has a front disc brake.

GB :mrgreen:
 

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Discussion Starter · #6 ·
Thread revival YAY!
I am going to check out a motorcycle junkyard sometime this month (its a 3 minute drive from my house) to look at what they have to offer. I can pretty much just ask for a 7/8" bar single disk master cylinder right? Be it from a random 70's UJM to a modern sportbike?
 

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Discussion Starter · #8 ·
Thank you!
 

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You do probably need to recondittion master cylinder but there should be some clearance between lever and brake M/C piston end.
On old Honda's there should also be a damper piece slid in from underneath which lever contacts to prevent rattles (at least the worst of them :( )
There is a thin steel plate bolted onto pivot bolt with dimple on end that holds 'damper' in place.
I just cut up a piece of thin pipe ( old breather tube, fish tank airline, anything similar) and put it in hole, its only about half inch long
PJ
 

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Discussion Starter · #10 ·
crazypj said:
You do probably need to recondittion master cylinder but there should be some clearance between lever and brake M/C piston end.
On old Honda's there should also be a damper piece slid in from underneath which lever contacts to prevent rattles (at least the worst of them :( )
There is a thin steel plate bolted onto pivot bolt with dimple on end that holds 'damper' in place.
I just cut up a piece of thin pipe ( old breather tube, fish tank airline, anything similar) and put it in hole, its only about half inch long
PJ
I actually have that part. Its down to either reconditioning the master cylinder or purchasing a replacement. Its not such a big deal since the front brake still works, its just the rattling is very annoying, especially on a vibrating CB360 :lol:
 

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krukster86 said:
I actually have that part. Its down to either reconditioning the master cylinder or purchasing a replacement. Its not such a big deal since the front brake still works, its just the rattling is very annoying, especially on a vibrating CB360 :lol:
If you remove the lever you'll probably find the damper is completely compressed or even rotted from brake fluid. It should be 'sticking out about 0.020".
I grease the pivot bolt as well as it helps a litle to dampen vibration.
Is the lever worn?
I've shimmed them with 0.010" brass washers.
As you say , its really annoying when riding to have lever buzzing about
PJ
 
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