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does the swingarm hit the linkage rod under full compression?

if not, looks good to me although the mechanical advntage of the foot lever to the brake lever does kinda look low...... ie..... short travel and high effort

I just set one up at 9:1

feels very good

..........looked closer and it appears it should be fine
 

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midge,

In that photo just above, from Chris, you'll notice that the backing plate should be firmly clamped against the swingarm. I'm not sure that the backing plate is going to rotate as the shocks compress and the swingarm goes up and down. At least it shouldn't. If it does then the backing plate isn't firmly clamped to the swingarm. And if the backing plate isn't firmly clamped then the wheel will be able to move forward in the swingarm. And that wouldn't be good. The cable set-up that you've got now will work. It may not be the most elegant but like I've said before you'll change a lot of things before you get it exactly the way you want it.

Move on to the next problem. Is it running yet? Will it rev beyond 9k with the points?

Craig
 

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The rod set up on the back brake looks nice - where did you get the parts from ?????
 

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Chris,

One of the benefits of a cable operated rear brake is that there isn't very often that you'll get a straight shot from the rearset/brake pedal to the lever on the brake backing plate. So what ends up happening is that people fab up a brake rod that bends around the swingarm and shock. The first thing that happens when you press on the brake pedal is that bent rod tries to straighten itself out. There is a loss of braking feel when this happens. On a rear brake it's probably not enough to make a difference. The cable operated brake eliminates this brake rod flex problem.
That and midge already spent a bunch of money on the fancy cable operated brake set-up and you can't give up on it at this point. :)

Craig
 

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Discussion Starter #105
you know graig this whole debate about the cable actuated rear brake just kind of got started, when i bought the rear set it came with the cable set up, so i installed it, i was not happy with the set up as it came so i made some mods and i feel very confident that i have a good brake right now, as for the back plate all i can say is the bike is sitting off the lift waiting for the motor to go in with no chain on, and im not even sure if i tightened the axel bolt, as i just put the wheels on to move the bike out of the way so i could get my new giro bike going,and do a few things on the rieju as well, i have moved on to my other problems i have a whole list of other problems, when i get the motor in ill be test riding it and if there are issues and im sure there will be a few, ill work them out, with some help from you guy, thanks
 

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When you're over tired, working late to get the bike ready for an event and you get everything tightened and safety wired and then see the torque rod hanging because you forgot to reattach it, then it's very evident that backing plate doesn't rotate.
I've missed it enough times wher it's not even funny to me anymore.
 

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yes on the cable stuff but they do have one problem...... friction

I removed the clutch cable from one of my bikes and fabbed up linkage

not a cafe bike but the bellcrank swings on a sealed DA contact beearing....... very smooth and no problems associated with that huge cable which makes a very sharp bend failing to allow the clutch to fully disengage



you can see the bellcrank here and somewhere on this site, I posted a pic which shows the other side which hooks into the clutch lever on the transmission...... this pic is from about 4 years ago

much has changed since

here is a close-up of the bellcrank

 

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I don't understand what you mean by the backing plate. I agree that cable systems can be made well, but I think that 1/8" steel cable will stretch as much as 3/8" 6061-T6 rod. That, and cable systems introduce a lot of friction; rod systems have less of this. I don't know which one is better. I do think the cable systems look pretty cool. But the problem that I'm reading and seeing with the cable system seems to approach a diminishing return. You know? If it were me, I'd copy a proven solution and move on to the next step.

The control rods were made by me. The rod ends cost $30 or so and the rod cost $10. Drill it out, tap it and away you go. For reference, I used 3/8" rod and 1/4" aluminum rod ends. They are pretty nice: aerospace spec with kevlar fabric on the race. I only use them in push/pull apllications though.

--Chris
 

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a wound stainless cable stretches very little

the outer housing can compress easier

a non-straight linkage rod that comes under tension does tend to straighten but the one shown appears to be a healthy 3/8" and should be just fine, I prefer stainless over T6 for linkage rods, under compression or in tension ..... matters not

T6 will fatigue, and unpredictably so, long before stainless will if both equally sized parts are subjected to the same number of cyclical loadings

the penalty of stainless is weight, and overall cost including machine-ability

I love Titanium too
 

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bfd,

I've never forgot the torque rod. I have, however, missed the brake rod itself. And had the wheel installed and torqued and safety wired and had to start over. I've done that one a couple of times. I agree that wasn't funny when I did it. I did laugh at yours though.

Craig
 
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