Bleeding ** brakes

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ME 109
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Re: Bleeding ** brakes

Post by ME 109 »

I've managed to ride the mountains in the rain a bit lately, some heavy rain too. My 81 twin discs suffered terribly.
Performance plummeted.
Lord of the Bings
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Bamboo812
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Re: Bleeding ** brakes

Post by Bamboo812 »

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enigmaT120
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Location: Falls City, OR

Re: Bleeding ** brakes

Post by enigmaT120 »

ME 109 wrote:I've managed to ride the mountains in the rain a bit lately, some heavy rain too. My 81 twin discs suffered terribly.
Performance plummeted.
The twin disks on my R65 work about as well wet as dry. Noisier though. Maybe they just suck dry, I don't know. I haven't run into anything.
Ed Miller
'81 R65
'70 Bonneville
Falls City, OR

"Gasoline makes people stupid." -- Chuey
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Rob
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Re: Bleeding ** brakes

Post by Rob »

My R65 single disk worked reasonably well, I thought.
Then I got the (very much lighter) 2012 CBR250R. Oh yeah! (modern headlight, too)

Too bad I am too scared to ride anymore.
Rob V
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dougie
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Re: Bleeding ** brakes

Post by dougie »

Rob wrote:My R65 single disk worked reasonably well, I thought.
Then I got the (very much lighter) 2012 CBR250R. Oh yeah! (modern headlight, too)
Too bad I am too scared to ride anymore.
Hey Rob - wondering if you have tried the CBR300R or CB300F? (I like the look of the "F".)
I've spent most of my money on women, motorcycles, and beer.
The rest of it I just wasted.
Rob
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Re: Bleeding ** brakes

Post by Rob »

dougie wrote:
Rob wrote:My R65 single disk worked reasonably well, I thought.
Then I got the (very much lighter) 2012 CBR250R. Oh yeah! (modern headlight, too)
Too bad I am too scared to ride anymore.
Hey Rob - wondering if you have tried the CBR300R or CB300F? (I like the look of the "F".)
I don't have a job, and I am tired of dressing up like the Michelin man to go for a ride. Nope. Done.
Motorcycling is for rich, on-the-median-side of well adjusted people.
I am neither.
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jagarra
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Location: Reno, Nevada

Re: Bleeding ** brakes

Post by jagarra »

My dual disc conversion has not gone smoothly. I received my sleeved 16mm M/C yesterday and I quickly installed it, but there were issues. I installed the kit that was in there before I sent it in for sleeving, the clip had lost some of it's tension as right after I installed it on the bike, it let go and guts shot out in pieces. When it came apart the piston portion fell apart leaving the seal stuck in the bore. Crap! Luckily I kept the original one, after I found that one and stripped the left over seals, I removed and installed the seals on the old piston. That's 3 stretches on the seals now, plus working in a pitted bore. After finding a good retaining clip I reinstalled the M/C on the bike. Bugger wouldn't bleed or move fluid from the reservoir. Not sure what is up, stopped playing with it as it started leaking out the front. Seals not good anymore? Scarred from working over a pitted bore?
I ended up drilling and tapping my old 14mm M/C for dual discs, I hooked everything up and bled the system, had some issues with a leak between the reservoir and the housing . An interesting bit of info on the threads of the hose that attaches to the M/C, turns out it is 1/8" pipe thread, I believe it is a straight thread rather than a tapered one, but it woks with no leaks.
Right now the system is being burped with the bungee cord holding the lever down overnight, seems to be getting a pretty good feel to it.
1974 R90/6 built 9/73
1987 BMW K75S
1994 BMW R1100RS
1964 T100SR Triumph
1986 Honda XL600R
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Airbear
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Location: Oz, lower right hand side, in a bit, just over the lumpy part.

Re: Bleeding ** brakes

Post by Airbear »

jagarra wrote:...
Right now the system is being burped with the bungee cord holding the lever down overnight, seems to be getting a pretty good feel to it.
Sympathy attached for the difficulties. Fingers crossed for a happy outcome.
Charlie
and Brunhilde - 1974 R90/6
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jagarra
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Re: Bleeding ** brakes

Post by jagarra »

Thanks Charlie,

I played with the 16mm M/C on the bench today trying to figure out what's up. I ran a hone through the bore and tried to install the piston assembly again, just didn't want to go. I figured a sleeve would be handy to maybe compress the seal and maybe slide it into the bore. I used a plastic hypodermic that I had I used for injecting oil in stuff, found one with an ID about the same as the M/C, so I cut the end off. Inserted the piston assy into it but it just wouldn't accept the forward seal, seems that the material was really floppy and had lost it's rigidity. I guess all those stretches killed it, cause it sure is floppy and basically useless. So another set of seals are in order. Right now I am still burping the system with the 14mm, maybe that will be OK.
1974 R90/6 built 9/73
1987 BMW K75S
1994 BMW R1100RS
1964 T100SR Triumph
1986 Honda XL600R
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Airbear
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Location: Oz, lower right hand side, in a bit, just over the lumpy part.

Re: Bleeding ** brakes

Post by Airbear »

I'd persevere with the 14mm. I'm pretty sure ChasBMW uses a 13mm (handlebar mounted) for his twin disk setup.
Charlie
and Brunhilde - 1974 R90/6
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Graduate, Wallace and Gromit School of Engineering and Design (Pending)
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