Author Topic: New disc caliper suitable for tandem use?  (Read 1541 times)

New disc caliper suitable for tandem use?
« on: June 07, 2013, 01:41:39 pm »
TRP have a pair of new calipers coming to market that look as though they will be suitable for use on the rear of tandems.  First reports show that the Spyre is not as powerful as a BB7 but TRP have confirmed to me that there are no plastic parts that could melt and the double action piston should ensure no drag when off.

The Hy-Rd is getting rave reviews and this this video shows that it would work very happily as a drag brake on the back of a tandem.

Pricey but not much compared to the overall cost of a custom tandem.

   

Re: New disc caliper suitable for tandem use?
« Reply #1 on: July 08, 2013, 11:13:26 am »
So that guy was running minimalist rotors (very little metal) and dragging his brakes?

I'm not surprised they failed. Wrong brakes for that use (he acknowledges that) and not used correctly. Haul on hard, release completely, haul on hard - that's the way to go on a solo bike.

He sounds to have been a tentative descender (like me). It's very tempting to hold on the brakes if you are like that; I kept doing that coming back from Tan Hill on the bit before the track.
<i>Marmite slave</i>

Re: New disc caliper suitable for tandem use?
« Reply #2 on: July 08, 2013, 11:51:42 am »
I'm quite taken by the idea of the Hy-Rd, abd cost wise they seem similar to Ti BB7's. Other of this parish are sceptical because the Hy-Rd uses bakelite as an insulator to stop heat soak into the (very small volume) hydraulic reservoir and subsequent boiling. Bakelite is (only) good to 250C.

The following is from a recent review (UK based).

"It's possible to induce a bit of heat-induced brake fade if you drag a single brake down one of Bath's many hills and then try and use it to stop at the bottom, but it's fairly predictable fade and once you're using both brakes together it really ceases to be an issue at all. Even with a bit of fade you're still applying much less pressure on the levers than you would with rim brakes.

Heat transfer to the actual calliper unit is minimal. Even when the rotors are piping hot the hydraulic system is barely warm. TRP uses a Bakelite piston to insulate the hydraulics against the braking heat and it seems to work. I haven't tried firing myself down an alpine col in the high heat of the summer with these brakes, but I wouldn't have any qualms about doing so."

I'll be trying a set on my road bike when they become available.

We are making a New World (Paul Nash, 1918)