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Tandem Cycling A bicycle built for two. Want to find out more about this wonderful world of tandems? Check out this forum to talk with other tandem enthusiasts. Captains and stokers welcome!

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Old 03-18-13, 04:56 PM   #1
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TRP Spyre mechanical brake = bee's knees?

I had posted previously about the TRP Spyre mechanical disc brake.

____________________________________________________________________________________________________ ___

The soon-to-be-introduced TRP Spyre... pushes both pads together.


Quote:
Originally Posted by Bike Rumor
Perhaps just as exciting is the new Spyre dual pull mechanical disc brake. Using a lever that rotates around bolts on both sides of the caliper and pushes both pads simultaneously and evenly, we expect itíll have smooth action and a comparatively powerful feel.

Presumably this is also aimed at the road/cyclocross crowd, meaning the leverage ratio might be designed around a drop bar leverís cable pull. For the uninitiated, having both pads move inward means easier set up and the ability to have a little more space between the pads and rotor when unengaged. It also means one pad isnít bending the rotor as it pushes it into the static pad like on current calipers like Avid BB7 and Hayes CX5, among others.

TRP claims the new Spyre and Spyre SLC cable actuated disc brakes are more than 20mm narrower than Avid's BB7.

Video shows operation of both pads...

[video=youtube_share;VovS0oT0xYA]http://youtu.be/VovS0oT0xYA[/video]

____________________________________________________________________________________________________ __________________

Now, more info today at Bike Radar, it includes news of a weight weenie version weighing only 141 grams. The Spyre really looks like an advancement on the venerable Avid BB7.

TRP Spyre road/CX disc brakes - full details

Just prior to the public unveiling here at the Taipei Cycle Show, TRP today released official information on the new Spyre road/cyclocross disc brakes that we previewed a few weeks ago.... TRP says that the cable-actuated Spyre will deliver 20 percent more power, 20mm more ankle clearance, 40g less weight, and more even pad wear than a standard BB7 thanks to its symmetrical dual-piston design.

Claimed weight on the complete standard Spyre is just 239g (front caliper with 160mm rotor and hardware) Ė 61g lighter than the new Avid BB7 SL Ė while the previously unofficial Spyre SLC cuts that down to 141g thanks to a molded carbon fiber arm.


The top-end TRP Spyre SLC incorporates a molded carbon fiber cable arm that brings the claimed caliper weight down to 146g.
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Old 03-18-13, 05:29 PM   #2
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That, is cool technology, finally coming to bikes! Probably $$$
R
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Old 03-18-13, 05:40 PM   #3
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It looks like the pads are as large as a Avid BB7 which is better then the pads on the Bengals many of us are using. The mechanical/ hydraulic units will be great if they have enough heat dissipation to prevent fluid boiling. The prices are not bad at $80-110 for the mechanical. The popularity of cycle cross and discs on road bikes is going to significantly add to the choices for the tandem market finally.
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Old 03-19-13, 05:56 AM   #4
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Pardon my ignorance but the IRD Dual Banger is a mechanical disk that pushes both pads together. Why is this brake such a new thing?
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Old 03-19-13, 08:51 AM   #5
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Pardon my ignorance but the IRD Dual Banger is a mechanical disk that pushes both pads together. Why is this brake such a new thing?

The IRD Dual Banger has a not so rosey history as far as the pad adjustments and weight, but otherwise reports are good. I like that it uses standard Shimano type pads that are readily available.

Maybe it's the hopes and dreams the Spyre will be a better mouse trap. Have not heard about the pad style on the TRP though.
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Old 03-19-13, 10:07 AM   #6
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Quote:
Originally Posted by twocicle View Post
The IRD Dual Banger has a not so rosey history as far as the pad adjustments and weight, but otherwise reports are good. I like that it uses standard Shimano type pads that are readily available.

Maybe it's the hopes and dreams the Spyre will be a better mouse trap. Have not heard about the pad style on the TRP though.
Posts on BikeRadar are informative.

Quote:
Originally Posted by ChrisC
@Danno -
The Spyre appears to work completely differently from the Dual Banger (more of a true dual piston style vs. the IRDís weird ďletís move part of the caliper body with a wonky cam set upĒ system), and the TRP is waaaaay lighter. The only similarity seems to be that both units move both brake pads together.
Quote:
Originally Posted by Zach Overholt
@JonDanger, they looked like the same pads TRP uses for the Parabox Ė so basically Shimano m515 sized pads.
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Old 03-20-13, 09:58 AM   #7
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Ritterview thanks for the heads up on these brakes. Put me in the front of the line as soon as these hit the market. I am hoping to pair the TRP's with the Hope V2 vented discs. I am currently running V2's front and back and can't see myself going back to a caliper brake.
I know that i added a lot of weight to the bike between the calipers, the heavier disc and the required fork but the improved braking is more than worth it. In the last few weeks we have descended Mt. Diablo, Metcalf, Hwy 9, West Old laHonda with complete confidence. The Metcalf descent is one I stay away from on a single. The brakes also passed the Mt Ventoux test with flying colors.
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Old 03-20-13, 12:11 PM   #8
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I am hoping to pair the TRP's with the Hope V2 vented discs. I am currently running V2's front and back and can't see myself going back to a caliper brake.... the improved braking is more than worth it. In the last few weeks we have descended Mt. Diablo, Metcalf, Hwy 9, West Old laHonda with complete confidence. The Metcalf descent is one I stay away from on a single. The brakes also passed the Mt Ventoux test with flying colors.
When I saw the mention of increased clearance with the dual action TRP Spyre, I had thought of the Hope Ventilated Rotor. Are you still using the modified BB7's, or do you have the Hope V2 (or now V4) hydraulic meant to be paired with the Ventilated Rotor?



Given the Hope Ventilated Disc's obvious increased heat management capacity, and your favorable experience, if the TRP Spyre can accommodate its additional width, then adequate brake heat management is available for all. The Hope is only 90 additional grams in comparison to an Avid steel 203 mm rotor (and since the Spyre reduces up to 40 grams from the BB7, that too is mitigated).
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Old 03-20-13, 12:32 PM   #9
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In your quest to lighten up a on disc brakes, did you see the Avid BB7 Ti bolt kits available?

http://www.imperialbikeco.com/produc...-Ti-bolts.html

No idea what the total weight savings might be, but it's got to be lighter than all those coins in your pocket.

Of course, if you grab a BB7 SL, it comes with some Ti hardware already (part of its claimed weight savings). Note, the SL is also spec'd with a HS1 rotor now (~174g for the 200mm rotor according to scale photo on mtbr.com), instead of the old (and heavy) G2. This link shows some of the weight breakdown: http://www.bikerumor.com/2013/02/05/...rake-calipers/

Last edited by twocicle; 03-20-13 at 01:06 PM.
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Old 03-20-13, 01:26 PM   #10
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Quote:
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When I saw the mention of increased clearance with the dual action TRP Spyre, I had thought of the Hope Ventilated Rotor. Are you still using the modified BB7's, or do you have the Hope V2 (or now V4) hydraulic meant to be paired with the Ventilated Rotor?



Given the Hope Ventilated Disc's obvious increased heat management capacity, and your favorable experience, if the TRP Spyre can accommodate its additional width, then adequate brake heat management is available for all. The Hope is only 90 additional grams in comparison to an Avid steel 203 mm rotor (and since the Spyre reduces up to 40 grams from the BB7, that too is mitigated).

I am running the ventalated discs with the modified Avid calipers. I was originally only running it in back but added the disc brake upfront for a trip to France last September. I had been installing new brake pads on the rear disc brake every 2 to 3 months. Since switching to front and rear disc brakes (both vented) I have not had to replace the pads. We have a team weight of about 340 and I am a cautious descender, I do not ride the brakes but do apply them aggresivley before entering a turn. I think the TRP's would reduce hand fatique because you would not be trying to bend the disc while braking. If it is ramped for road levers it would also eliminate the brake power booster that i use.
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Old 03-20-13, 01:53 PM   #11
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Quote:
Originally Posted by twocicle View Post
In your quest to lighten up a on disc brakes, did you see the Avid BB7 Ti bolt kits available?[/URL]
Yeah, the new lighter version BB7 SL isn't that exciting, because its mainly just Ti bolts. The new standard TRP Spyre weighs about the same as the BB7 SL.



And at 146 grams, the Tyrp Spyre SLC is lighter still, and this may be with steel hardware that can be replaced with Ti.



This weight weenie braking fest is not over for me, as shipping this week will be the Kettle Cycles SiCCC SFL 203mm silicon carbide/ceramic/carbon fiber rotor, weighing about half that of an Avid 203 mm.



If the SiCCC SFL and the TRP Spyre SLC both work out, disc brakes are going to be not that much heavier than rim calipers. That could shake things up in tandems and beyond.
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Old 03-20-13, 03:42 PM   #12
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Quote:
Originally Posted by twocicle View Post
The IRD Dual Banger has a not so rosey history as far as the pad adjustments and weight, but otherwise reports are good. I like that it uses standard Shimano type pads that are readily available.

Maybe it's the hopes and dreams the Spyre will be a better mouse trap. Have not heard about the pad style on the TRP though.
But they have a history to snipe on. These nooby toy needs to get out there and get ridden by folks willing to break it and wear it out. Looking forward to seeing the results data.

/K
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Old 03-21-13, 02:48 AM   #13
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Y
This weight weenie braking fest is not over for me, as shipping this week will be the Kettle Cycles SiCCC SFL 203mm silicon carbide/ceramic/carbon fiber rotor, weighing about half that of an Avid 203 mm.
That's crazy! Let us know how that rotor works out.... Myself, I'd be scared to try it!
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Old 03-21-13, 09:37 AM   #14
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For a lightweight disc setup it looks very slim. Though the total weight is still not close to a rim caliper:

TRP Spyre SL @ 146g + lightest 203mm SiCCC SFL rotor @ 94g + 200/203mm ISO bracket @ 30g(?) + extra cable/casing to reach disc caliper (?) = ~ +270g

By comparison of a standard rear brake caliper, ie:, Shimano 6700 = 150g = minimum of 120g lighter.

I am more interested in hearing the results of performance testing this setup when it's all available. Definitely slim & bling

Last edited by twocicle; 03-24-13 at 11:49 AM. Reason: typo
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Old 03-21-13, 05:18 PM   #15
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Tough the total weight is still not close to a rim caliper:

TRP Spyre SL @ 146g + lightest 203mm SiCCC SFL rotor @ 94g + 200/203mm ISO bracket @ 30g(?) + extra cable/casing to reach disc caliper (?) = ~ +270g

By comparison of a standard rear brake caliper, ie:, Shimano 6700 = 150g = minimum of 120g lighter.
The need for a 30 gram ISO bracket adapter is weight weenie buzz kill. The way Calfee has the disc brake drop out and mount seems like an inelegant and unparsimonious afterthought. There is the mass of the dropout, and then the need for the adapter robust enough to support the disc caliper hanging way out in back. Why a 160 to 203 mm adapter? Everyone knows the rotor on the tandem is going to be at least 203 mm.



Co-Motion is on the right track with its integrated mount incorporated into the rear triangle.


Co-Motion tucks the rear caliper neatly inside the rear triangle
© James Huang/Future Publishing


In Cyclocross, new bikes are feature discs, and the disc mounts are incorporated more organically into the design of the frame. Designing a disc mount into the frame, instead of relegating it to the drop out, should mitigate the mount/adapter weight penalty. The weight reduction and improvements in the caliper/rotor encourages discs to be more standard in equipment, which in turn promotes improvement in the frames to accommodate this development.




Raleigh mounts the RXC Pro Disc's rear brake on the chain stay.
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Old 03-23-13, 12:55 AM   #16
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The only problem with integrating a mount into the frame that is designed for a larger rotor is that the size of the larger rotors still aren't very standardized. Avid always used to have 185 or 203 mm rotors as their larger rotors, but have just switched these to be 180 and 200 mm. So which size are you going to design your mount for? Rear mounts have normally been designed for 140mm rotors, which could admittedly be increased to 160mm, which then would at least be the same as the front, so in fact fewer versions of the adaptors would need to be produced. However, the only variation on this that I've seen lately is that some cyclocross forks are being made with mounts that would allow a 140 mm rotor on the front (instead of 160 mm being the smallest on most forks), due to being designed as pure race machines for short, technical circuit riding.
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Old 03-23-13, 01:15 AM   #17
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Gusset has one as well, looks so much like IRD's I wonder if same Manufacturer has 2 importing contracts

1 matte black, the IRD , is Polished,
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Old 03-23-13, 09:30 AM   #18
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Yeah, I don't believe builders should make an assumption to standardize a mimimum disc size (and caliper position) other than to provide a standard ISO offset and then we use the appropriate adapter for the disc size we chose. This isn't like a rim brake caliper where we know the wheels size is not going to change. Case in point with Avid moving from 203mm to 200mm. Did they really need to change or was that because some people couldn't get their heads around the odd number?
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Old 03-23-13, 10:34 AM   #19
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Quote:
Originally Posted by twocicle View Post
Yeah, I don't believe builders should make an assumption to standardize a mimimum disc size (and caliper position) other than to provide a standard ISO offset and then we use the appropriate adapter for the disc size we chose. This isn't like a rim brake caliper where we know the wheels size is not going to change. Case in point with Avid moving from 203mm to 200mm. Did they really need to change or was that because some people couldn't get their heads around the odd number?
I suspect that 203mm was a 8 inches converted to metric while 200mm is a more normal metric designation. Similar to move from 27 inch wheels to 700C.
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Old 03-23-13, 11:05 AM   #20
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Actually 27" is an even 630 BSD- ETRO spec, 700C [ a french wheel size niche, including an A & a B also]
is 622..

The 700c Rim is to be compatible for clincher training wheels on bikes ,
made for the 28" sew-up tires Pro Racers use.

People bought a lot of racer replica bikes , so $ Voted with the southern shore
of the English channel..

So manufacturers concentrated on the French Wheel size.
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Old 03-24-13, 01:37 AM   #21
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I suspect that 203mm was a 8 inches converted to metric while 200mm is a more normal metric designation. Similar to move from 27 inch wheels to 700C.
That's what I heard from Avid's marketing, that they wanted to make the differences in sizes constant, now making it 140, 160, 180, 200. Also, Shimano is already using 180 instead of 185, so this removes one of the odd-ball sizes.
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Old 03-24-13, 11:59 AM   #22
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I don't mind the disc caliper mount being behind the dropout as Calfee and many other builders do, because it results in little to no restriction in the caliper positioning needed for various rotor sizes. The mechanical/cable routing to the rear mounted caliper is more direct and results in better brake cable performance.

Conversely, on our previous Santana that had the mount on the chainstay, that posed a very real restriction on the caliper mount position and the cable routing under and around the stoker BB made the "stiction" more problematic. On the plus side, the chainstay mount may be a stronger implementation than hanging off the rear dropout or a pencil thin seatstay. It is also better for keeping out of the way of rear pannier rack mounts.

So, merits and demerits for both.
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Old 03-25-13, 02:42 PM   #23
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From experience, the 160mm style caliper perch, chainstay mounted is best in many ways. There is less weight, there is less lateral flex, chainstays are stronger than a dropout. All except the less weight make the brakes work better.

As for the cable run, if the bike does have an acceptable route, such as a diagonal frame tube, the alignment is pretty much perfect with the shortest cable route possible.

As evidence to compare, we have experience with three tandems with disc brakes. A Fandango 29 off-road tandem, a Ventana 26 full suspension off-road tandem andour Co-Motion Roadster with front and rear disc brakes.

The Co-Motion stops very well, but has obvious frame flex and torquing of the LS dropout. Not that I have seriously tried, but on dry pavement I am not convinced the Co-motion can skid the rear tire. It may but might be enough stress to damage the dropout with the leverage provided by the perch and radius of the brake. The caliper is mounted similar to the Calfee and is without any bracing.

The Ventana also stops well, it also has visible chainstay and dropout flex. There is no means to flex the seatstay or entire frame since the brake caliper is dropout mounted on the lower suspension arm (swingarm). This bike sees very heavy braking in all forms of terrain, some low grip other times high grip. It is not uncommon to be on the brakes so hard to have them lock up or induce brake chatter in hacked entries to corners.

The best tandem disc brakes on a tandem we have owned that were cable operated were on the Fandango. Alex did a very good job of placing the caliper on the LS chainstay. The mounting perch is based on a 160 series mount but designed for a 203 rotor. Once installed, this brake is rock solid in feel and can easily skid the big 2.35 rear tire on asphalt.

In this teams experience it does make a difference.

PK
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Old 03-25-13, 03:37 PM   #24
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Quote:
Originally Posted by fietsbob View Post
Actually 27" is an even 630 BSD- ETRO spec, 700C [ a french wheel size niche, including an A & a B also]
is 622..

The 700c Rim is to be compatible for clincher training wheels on bikes ,
made for the 28" sew-up tires Pro Racers use.

People bought a lot of racer replica bikes , so $ Voted with the southern shore
of the English channel..

So manufacturers concentrated on the French Wheel size.

Good point. I choose a bad example that actually went the incorrect direction!
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Old 03-25-13, 03:48 PM   #25
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Disc brake caliiper placement

Quote:
Originally Posted by PMK View Post
From experience, the 160mm style caliper perch, chainstay mounted is best in many ways. There is less weight, there is less lateral flex, chainstays are stronger than a dropout. All except the less weight make the brakes work better.

As for the cable run, if the bike does have an acceptable route, such as a diagonal frame tube, the alignment is pretty much perfect with the shortest cable route possible.

As evidence to compare, we have experience with three tandems with disc brakes. A Fandango 29 off-road tandem, a Ventana 26 full suspension off-road tandem andour Co-Motion Roadster with front and rear disc brakes.

The Co-Motion stops very well, but has obvious frame flex and torquing of the LS dropout. Not that I have seriously tried, but on dry pavement I am not convinced the Co-motion can skid the rear tire. It may but might be enough stress to damage the dropout with the leverage provided by the perch and radius of the brake. The caliper is mounted similar to the Calfee and is without any bracing.

The Ventana also stops well, it also has visible chainstay and dropout flex. There is no means to flex the seatstay or entire frame since the brake caliper is dropout mounted on the lower suspension arm (swingarm). This bike sees very heavy braking in all forms of terrain, some low grip other times high grip. It is not uncommon to be on the brakes so hard to have them lock up or induce brake chatter in hacked entries to corners.

The best tandem disc brakes on a tandem we have owned that were cable operated were on the Fandango. Alex did a very good job of placing the caliper on the LS chainstay. The mounting perch is based on a 160 series mount but designed for a 203 rotor. Once installed, this brake is rock solid in feel and can easily skid the big 2.35 rear tire on asphalt.

In this teams experience it does make a difference.

PK
PK - are you running Avid BB7 on all 3 bikes?

I had not really thought of placement of the caliper until now. My perception has been that the brakes are most affected by the type of brakes and had not contemplated the placement of the caliper. I will say that I am unimpressed with the BB7. Possibly it has not been set up well, but I just have never thought that the BB7 brake was all that. Here's my points of reference.

* DaVinci Global Venture 26" wheels with Avid BB7 rear brake mounted to the chainstay. Seemed like ideal placement and was out of the way for racks/panniers. This seemed to work fine, but I had no point of reference.
* Calfee Dragonfly 700c wheels with Avid BB7 mounted off the back as noted here in this thread. Placement may have not been ideal, but I did not notice a difference in the braking between the Calfee and the DaVinci. They both seemed adequate.
* Ventana ECDM - 26" wheels full suspension MTB with Magura Louise hydraulic brakes mounted off the seat stay as mentioned by PMK. The Hydraulic disc on the tandem was eye opening to me!
* Fandango 29" wheels hard tail MTB with Magura Louise hydraulic brakes mounted off the chain stay. Works great, but I have not noticed much difference bewteen the seat stay and chain stay mounting.
* Ventana 29" wheels full suspension MTB with Magura MT6 hydraulic brakes mounted off the seat stay (again like PMK noted on his Ventana). I do prefer the MT6 brakes to the Louise brakes... but that is another story.

My only point here is that in my mind, the placement of the caliper has been all but irrelevant in my mind (at least until now - maybe I'll become more aware?). What has been most noticeable to me is the stopping power of Hydraulic brakes vs. Mechanical BB7 brakes. Night and day as far as I'm concerned. Now with that said, we've all read about boiling hydraulic brakes and the fact that they may not be suitable for road bikes...

So where does that leave me? I'll be seeking out either the Bengal mechanical brake or the new TRP Spyre mechnical for my next road tandem (which will also be equipped with rim brakes front and rear but with the option of running disc as well).


I am interested to hear other's take on the disc caliper placement and whether it is believed to have a strong influence on stopping power. I am not an engineer, but can only speak to my own real world experiences and observations.

Last edited by colotandem; 03-25-13 at 04:33 PM.
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