Front Brake needs some hand muscle - ATE single disk

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jjwithers
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Re: Front Brake needs some hand muscle - ATE single disk

Post by jjwithers » Thu May 04, 2017 9:04 pm

I really hate dealing with bleeding brakes and brake fluid. I always make a mess and wonder if i got all the air out of the line.

Before i go switching master cylinders, i am considering:
using a vented disk vs solid disk
changing brake pads,
adjusting the cable tension between the handle and the master

Those, to me, are easy fixes to experiment with.

Getting new brake lines and a handlebar master is expensive, and going to require some messy bleeding. So I figure the nuts and bolts stuff is a good place to start.
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Re: Front Brake needs some hand muscle - ATE single disk

Post by Rob » Thu May 04, 2017 9:58 pm

"really old set of brake pads" has haunted me from the original post.

I would start with those. Maybe shop around for a soft compound?

I think the biggest gain you would see with a new disc would be only if the groves in the old one were a problem.
My original disc (holey) on my R65 looked like rings of Saturn before I replaced it. I thought it was still stopping the bike well, I just couldn't pass up a great sale price on a new EBC rotor.
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jjwithers
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Re: Front Brake needs some hand muscle - ATE single disk

Post by jjwithers » Thu May 04, 2017 10:22 pm

Yea, part of me thinks that the pads are glazed due to age. I know new pads have to 'bed' in with the old rotor but after 20-50 miles, I should know if the pads are the solution or not.
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Re: Front Brake needs some hand muscle - ATE single disk

Post by Chuey » Mon May 08, 2017 12:30 am

The same thing happens with bicycle brakes. The brake lever is the "master cylinder" and the brake is like the caliper. I refer to rim brakes here.

If the brake lever pulls too much cable you will have a very firm but essentially ineffective brake. If the lever pulls too little cable in relation to the caliper needs, it will feel very mushy but have a lot of stopping force.

As a side note: I doubt that a properly set-up and lubricated cable will contribute to ineffectiveness in the system. If there is any "stretch" in the cable, it is almost certainly compression in the cable housing. These are very stout cables on these bikes. I doubt very seriously that they stretch with the amount of force applied in braking.

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Re: Front Brake needs some hand muscle - ATE single disk

Post by jjwithers » Thu May 18, 2017 2:25 am

I changed the brake pads to new EBC pads and made sure the pads were aligned with the rotor. When removing the old pads, the contact area on the pad closest to the spokes was not making total contact with the rotor.
I also adjusted the cable at the handle.
These helped a wee bit but the handle still feels stiff overall.

I thought I bought a 13mm master cylinder but the seller sold me a 16mm despite specifically asking many times if it was 13mm. I was planning on doing the conversion but now I'm on the hunt for some affordable used parts to do the conversion.
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Re: Front Brake needs some hand muscle - ATE single disk

Post by Rob » Thu May 18, 2017 2:31 am

Next time ask for a photo of the casting on the bottom, lying on a current edition of the local paper!

But seriously, if they have a location marker on Google Maps, you can leave a review.
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Re: Front Brake needs some hand muscle - ATE single disk

Post by jjwithers » Thu May 18, 2017 2:32 am

It is somebody I do business with often so I am very surprised... and upset.
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Re: Front Brake needs some hand muscle - ATE single disk

Post by Rob » Thu May 18, 2017 2:51 am

In that case, condolences.
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Ken in Oklahoma
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Re: Front Brake needs some hand muscle - ATE single disk

Post by Ken in Oklahoma » Fri May 19, 2017 7:24 am

jjwithers wrote:
Thu May 18, 2017 2:25 am
I changed the brake pads to new EBC pads and made sure the pads were aligned with the rotor. When removing the old pads, the contact area on the pad closest to the spokes was not making total contact with the rotor.
I also adjusted the cable at the handle.
These helped a wee bit but the handle still feels stiff overall.

I thought I bought a 13mm master cylinder but the seller sold me a 16mm despite specifically asking many times if it was 13mm. I was planning on doing the conversion but now I'm on the hunt for some affordable used parts to do the conversion.
There is a better way to optimize contact between the brake pad and the rotor. The manuals would have you mark the rotor with something akin to a marks-a-lot. The idea is to take the bike for a short (very short) run and squeeze the brake lever. Then you examine the rotor and see if the marks-a-lot color has been wiped away cleanly by the brake pad. (It never is cleanly wiped away.) Then you take the cap off the bottom of the fork leg and adjust the eccentric as indicated by where the marks-a-lot is wiped away and where it is not. This is sort of a by guess and by golly proposition. Anyhow you keep working at getting the brake pad square with the rotor, which will be indicated by the marks on the rotor being wiped away cleanly.

Very frustrating!

Here's the way I invented to square the pad with the rotor. Other people (including Duane Ausherman) have developed the technique before I did. I just didn't know about it then.

Make some rubber bands out of a motorcycle inner tube, say about 3/8" to 1/2" in width. Now squeeze the brake lever and keep it squeezed with the rubber bands you loop over the brake lever and the handlebar. Now you go to that eccentric at the bottom of the fork leg and you rotate it a bit back and forth until you find where the eccentric position 'wants' to be. At that point the brake pads are square with the rotor. You can't get the alignment any better. Button things up, take or short ride (or spin the wheel by hand) and look at the marks-a-lot marks. They will be rubbed away nicely where the pad drags across the rotor.

The braking will now be as good as it can be, which as you know still isn't very good with just a single rotor. But it is better.

Ken
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Re: Front Brake needs some hand muscle - ATE single disk

Post by Seth » Fri May 19, 2017 8:26 pm

I do a similar thing, but I seem to be able to reach the brake lever while adjusting the pin. By pumping the handle, it's easier to turn the pin when the is no to little pressure.

But the pin also moves the caliper in and out in relationship to the axle. You want it in the far position to get the best leverage on the rotor.

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