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Hydraulic Brakes

Started by Chief of the Boat, July 31, 2023, 07:17:34 AM

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Chief of the Boat

Looking for recommendations on what to buy for hydraulic brake upgrade for my RadRover5?  Rotors too?  Thanks Terry


search area 13.  great products and customer service.


I see Area 13 has Juin Tech calipers, which are self-contained hydraulic calipers, meaning you can use your stock levers and cables.

Last year, this guy tested them against similar calipers of another brand and strictly mechanical calipers.

In 10 stops apiece from 25 mph, the Juin Tech stopped 5% shorter than the other two, 13.3 meters vs 14. He was amazed that there was so little difference.

13.3 meters is 44 feet. I've ridden my RadMission daily for 10 or 11 months, and I don't recall any maintenance to the front brake since the initial adjustment. From 20 mph on dry pavement I can stop in 20 feet with the front brake alone. That would translate to 31 feet from 25 miles an hour.

His narrative pointed to the reason he needed 42% longer, even with both brakes. He said he shifted his weight as far back as he could and pulled the levers as hard as he dared. He noted that stopping so short put a tremendous strain on his arms.

His deceleration was 0.5g. With low bars, restraining his weight from being thrown forward put quite a strain on his arms. However strong his arms were, braking harder could have thrown him over the bars or sent the bike end over end. I, on the other hand, had no trouble with a 0.7g stop because I had moved the seat and bars to get the seating position that was typical when Europeans depended on bicycles instead of cars.

If a mechanical disk brake is working properly, I think it can provide more braking power than a bicyclist can use. I think there's a demand for hydraulic brakes because mechanical ones often aren't working right. My back brake is an example. Often, the disk and pads seem to have less friction so that I would have to pull harder on the lever to get the same braking as the front.

The difference is the cable. A cable housing is made from a spring whose coils can separate slightly to allow flexing, and the rear cable flexes every time I turn the handlebars. Little by little it stretches, in effect making the center wire shorter and causing the pads to drag lightly. Continual dragging seems to produce surfaces that require more lever force for the same braking. When I squeeze the lever, the stretched cable will compress, giving the brake a spongy feel. Because the stretching process causes dragging, the pads will eventually wear until I can squeeze the lever all the way to the hand grip.

To correct stretching of the rear cable, I used to leave the lever tied with a clove hitch. Now I use a strap of velcro with a metal ring, which I can pull tight with a 2 to 1 mechanical advantage. This is a way to leave the housing under compression overnight.

The guy who made the video says he uses Jagwire KEB-SL housing because it's compressionless, not being made of a spring coil.

He said hydraulic calipers must be cleaned or the pistons will stick and drag like mechanical brakes with stretching cable housings.

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