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Is it just me or does this setup seem a little sketchy?

s-l1600.jpg

Overall the bike looks cool and period but that has me scratching my head. Looks like a front master. Seems like it was more work to engineer that than fitting a rear master. I've had ones not work because they were tilted with too little fluid.

s-l1600.jpg

Kawasaki Other | eBay
 

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Looking at the rear sets it's about as low key as you can get as far as fabrication. It would have been quite simple to cut a pie cut out of the shaft the M/C is bolted to and weld it back to make it more level.
 

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How is the brake activated? I see connection between the pedal and master cylinder. I know next to nothing about juice brakes, but that setup just does not look like it would work at all.

Also The use of a zip tie as a brake system parts makes the entire bike suspect.
 

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Probably one of Ichiban's old bikes :cool:

I guess the good news is you could easily replace the MC with a remote reservoir one off a newer bike and mount the reservoir upright.
 

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Death Trap

The front brakes look even scarier to me, look at how the flexible brake lines are connected to the solid tube, that union is suppose to be secured so that the solid tubing isn't subjected to flex. Failure is imminent.

The mounting brackets to lay down on the rear shocks are apparent on one of the other photos and they need some more zip ties to make them work too, but at least that might not kill you outright. s-l1600.jpg
 

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Pretty obvious that the zip tie is not in any way associated with the brakes. MC pushrod must be hidden behind that mount. I have used that same mc at some pretty extreme angles, but always on the handle bars, never was a problem, but that is taking it too far. It would be simple enough to unbolt mc, hold it level, fill it, cap it, then bolt it back on but I feel like you can see brake fluid damaged paint on the swingarm.
 

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I can't imagine how he expects to get the cap off so I am unwilling to say it is smart. Not sure what you are asking about is "safe" or not. <br><br>Is it safe to use a front master as a rear? sure. A master cylinder is just a pump, it doesn't know whether it is at the front of the bike or the back, so long as it is still properly sized for the brake it is operating. Goldstein's old H1 uses a cb750 front master to pump a a grimeca rear caliper and he raced with that setup for decades. you can see it mounted in this pic:<br><br><br>If you are asking is it safe to be at that angle....well....maybe. I would have to look but as long as the two holes are in fluid and always going to be in fluid then there is low risk in introducing air. I don't know that I have a lot of confidence in one at that angle but then again I don't rely on the rear brake for much anyway other than to settle the rear end when braking hard for a corner. <br><br>If you are asking me if it is a smart design? no I don't think it is. for one it doesn't look easy to service, you have to remove the master from it's mount to open the cap. second it places more of a load on the cap seal to prevent leaking by having gravity try and pull fluid through that seal. The cap seal on those is not really all that great, I don't think it was ever intended to operate in a vertical or on it's side so it is probably inviting the master to leak a lot - required more frequent service from something less easy to service. I also think by not having the fluid passage intake and return at the lowest point you open up the possibility of the passages being exposed to air in a turn or under hard braking. <br><br>
 

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I'll start by saying I don't like it but... To fill he has to take it off the mount and to bleed it as well. I would have done something very different, but maybe this was all he had?
 

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If you are asking is it safe to be at that angle....well....maybe. I would have to look but as long as the two holes are in fluid and always going to be in fluid then there is low risk in introducing air. I don't know that I have a lot of confidence in one at that angle but then again I don't rely on the rear brake for much anyway other than to settle the rear end when braking hard for a corner. <br><br>If you are asking me if it is a smart design? no I don't think it is. for one it doesn't look easy to service, you have to remove the master from it's mount to open the cap. second it places more of a load on the cap seal to prevent leaking by having gravity try and pull fluid through that seal. The cap seal on those is not really all that great, I don't think it was ever intended to operate in a vertical or on it's side so it is probably inviting the master to leak a lot - required more frequent service from something less easy to service. I also think by not having the fluid passage intake and return at the lowest point you open up the possibility of the passages being exposed to air in a turn or under hard braking. <br><br>
To the OP, also remember that what may work in a static system can fail in a dynamic one. With the bike running, it will be bounced around and sloshing the brake fluid. With the reservoir at that angle, it would be next to impossible to top off the level without removing the reservoir from the bike. Brake systems have rubber inserts that suck down as the fluid level drops not just to seal the system (a basic o-ring will do the same thing), but to keep air from infiltrating and to control fluid slop. The transfer holes could easily become uncovered under use, allowing the system to suck air into the hoses. With the angle of the hose out of the master, that air will go up the hose and build a bubble in the line that will be difficult to purge.
 

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If it was a race bike I would be less concerned as the brakes are probably addressed before each race anyway. This bike doesn't look like it was a real racer though. Fluid doesn't go away quickly, so I doubt it was much of an issue for the owner. I would have done it differently, but that doesn't mean what he made do with doesn't work safely.
 

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To the OP, also remember that what may work in a static system can fail in a dynamic one. With the bike running, it will be bounced around and sloshing the brake fluid. With the reservoir at that angle, it would be next to impossible to top off the level without removing the reservoir from the bike. Brake systems have rubber inserts that suck down as the fluid level drops not just to seal the system (a basic o-ring will do the same thing), but to keep air from infiltrating and to control fluid slop. The transfer holes could easily become uncovered under use, allowing the system to suck air into the hoses. With the angle of the hose out of the master, that air will go up the hose and build a bubble in the line that will be difficult to purge.
+1 to that:
Every time he goes down a steep hill his brake is going to suck air:



Then it's going to get all mushy and when that front brake fails, he's going to die a horrible death coming hard into turn 3.
 

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True story - I had a friend one time that had overfilled his front brake reserve in a cold garage. He then proceeded to jump on the same bike and drive down a driveway to retrieve his mail (about 1/8th mile). He then returns from the mail box up the driveway balls to the wall flying a giant wheelie doing about 60mph (ktm 540 mc). When the front wheel set down on the ground the front brake was totally locked up and he when over the handle bars with no helmet on. Even tho he landed on his lawn, he got pretty well banged up. Moral of the story - follow the mfg's recommendations for brake systems.
 

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Anything is possible to go wrong in a race scenario. I keep remembering a friend of mine who had a CBR600 race bike some years ago. He would put it down on a semi-regular basis. One time he dropped the bike and did a fair bit of damage. He re-built it all and then headed out for another meeting.

All was good until he was coming down the straight and tried to apply the front brake....but there was no lever.

The lever must have had a knock on it from a previous fall and this time round it decided to break off whilst going down the straight. It looked OK when he was rebuilding it, but it must have had some fractures in it.

Queue re-build #231......
 
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