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Avid BB7 - brake disk and pad options, tandem specific?

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Avid BB7 - brake disk and pad options, tandem specific?

Old 07-23-16, 11:47 AM
  #1  
bikefriday
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Avid BB7 - brake disk and pad options, tandem specific?

My wife and I are loving our new Co-motion Mocha with the Avid BB7 mechanical disk brakes (200mm rotors, and metallic pads). However, on the hilly roads we are frequenting around our house, I find that the front rotor sometimes warps and then makes a rubbing sound after cooling. Not a significant drag on the wheel when spinning, but noisy. I've also tried straightening the rotor with my Park tool...but that's tough and time consuming.
My question to the group is...what options are there out there for improvements that might prevent this from happening? I've seen finned brake pads, larger rotors (203mm), different rotors (Hope, etc), floating rotors, and different pad materials. However, at this early stage in our Tandem life I don't have the experience to form an opinion, and wanted to poll others before making any purchases. Wondering what works for others, and what the groups opinions are?

Thanks in advance for any help with this.
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Old 07-23-16, 04:08 PM
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marciero
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There is a very long thread here with a lot of information and opinion on disk brakes. Search and you will find it. I'm in the middle of this right now also, experimenting with different discs, calipers, pads. Your issue seems to be heat dissipation, and could be addressed with rotors.
BTW, am pretty sure "200mm" is more of a nominal size-the actual size of your rotors may in fact be 203mm. Regardless, an increase from 200 to 203 will be imperceptible. I am pretty sure that a larger rotor-the 10-inch that Santana specs on the rear of their bikes- is really not an option unless the frame is designed for it.

Hope makes vented and/or floating rotors which some report cool better. But you may have clearance issues with the thickness of the vented on BB7. (I read here or elsewhere where someone successfully grinding/machining a wider slot in calipers to accept a thicker rotor, cant recall which calipers).
Also, apparently the rivets on some versions of the Hope rotor are close enough to the braking surface, and stick out far enough, that they will foul the calipers.

You may be able to address this simply with braking technique-not riding the brakes, alternating front and rear, etc. There is discussion about this also, buried in various threads.

Last edited by marciero; 07-23-16 at 04:18 PM.
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Old 07-23-16, 04:14 PM
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thicker Galfer - Magura Rotor?

LBS repair seen.. had Single MTB's get the brakes hot enough to partially melt the BB7 outer knob.
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Old 07-23-16, 06:46 PM
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Try EB gold or Swiss Stop sintered pads.
I've changed from the Avids to TRP Spyre and am liking them better and they are also easier to adjust.
We also have a Mocha Co-Pilot.
Our latest upgrade has been to Blunt 35 rims which has made the Marathon Supremes 2.0 handle a lot better

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Old 07-24-16, 06:19 AM
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I have the Avid BB7's 203mm rotors on my 2009 Cannondale RT2. Just bought the bike a few months ago, PO had flat bars and MTB levers. It would stop on a dime, but screech like crazy. I've just went back with road bars and 105 brake/shifters.

I used my orbital sander and scuffed the rotors good, put new avid pads on, and bedded them in. Screech is gone, but I sure don't have the braking power that the MTB levers applied. I think the bike came out OEM with Problem Solvers Travel Agents to increase the amount of cable travel when using road levers, but I'm hoping I can get by without them by tuning the brake pads as close to the rotors as possible. I live west of Houston and it's flat as a pancake; brakes don't get a lot of use.

So I'm not answering any of your question, but wanted to ask you if your Co-motion came with travel agents?
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Old 07-24-16, 10:01 AM
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Using organic pads. Easy on the rotor. For durability a Hayes rotor can take lot's of abuse.
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Old 07-24-16, 11:15 PM
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Originally Posted by bikefriday View Post
My wife and I are loving our new Co-motion Mocha with the Avid BB7 mechanical disk brakes (200mm rotors, and metallic pads). However, on the hilly roads we are frequenting around our house, I find that the front rotor sometimes warps and then makes a rubbing sound after cooling. Not a significant drag on the wheel when spinning, but noisy. I've also tried straightening the rotor with my Park tool...but that's tough and time consuming.
My question to the group is...what options are there out there for improvements that might prevent this from happening? I've seen finned brake pads, larger rotors (203mm), different rotors (Hope, etc), floating rotors, and different pad materials. However, at this early stage in our Tandem life I don't have the experience to form an opinion, and wanted to poll others before making any purchases. Wondering what works for others, and what the groups opinions are?

Thanks in advance for any help with this.
Welcome to the site!

The BB7 was designed for single bikes, and it has largely fallen out of favor due to far better designs. It's rare to find the BB7 on new single bikes (mid to high-end) due to its single piston design. The BB7 uses one piston to push a pad against the rotor until it flexes against a fixed pad. It's difficult to setup the BB7 to be quiet and provide enough braking power for steep descents. The constant rubbing may explain your warped rotor.

By comparison, the TRP Hy/Rd and Shimano R785 hydraulic brakes use dual pistons to squeeze the rotor from both sides. They're quiet and are powerful enough to long, steep descents (8-12%). The Hy/Rd should be compatible with your Shimano 105 shifters, while the R785 brakes will require new shifters. Check with Co-Motion to see if the Mocha rear triangle can handle a hydraulic brake. If your team weight is around 300 lbs, you can probably use 180mm rotors with the R785.

In our experience, the Hy/Rd and R785 are substantially better than the BB7, regardless of the pad or rotor combination. If the BB7 is not good enough for a 170lb rider on a single bike, why use it for a 300lb tandem team?
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Old 07-25-16, 05:13 AM
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Originally Posted by mtseymour View Post
Welcome to the site!

The BB7 was designed for single bikes, and it has largely fallen out of favor due to far better designs. It's rare to find the BB7 on new single bikes (mid to high-end) due to its single piston design. The BB7 uses one piston to push a pad against the rotor until it flexes against a fixed pad. It's difficult to setup the BB7 to be quiet and provide enough braking power for steep descents. The constant rubbing may explain your warped rotor.

By comparison, the TRP Hy/Rd and Shimano R785 hydraulic brakes use dual pistons to squeeze the rotor from both sides. They're quiet and are powerful enough to long, steep descents (8-12%). The Hy/Rd should be compatible with your Shimano 105 shifters, while the R785 brakes will require new shifters. Check with Co-Motion to see if the Mocha rear triangle can handle a hydraulic brake. If your team weight is around 300 lbs, you can probably use 180mm rotors with the R785.

In our experience, the Hy/Rd and R785 are substantially better than the BB7, regardless of the pad or rotor combination. If the BB7 is not good enough for a 170lb rider on a single bike, why use it for a 300lb tandem team?
Going "full hydro" with road setup means giving up the triple chainring, I'm pretty sure, and converting to 11-speed (assuming your bike is 10-speed as is stock on comotion), a very big expense requiring replacing shifters and all the drive train parts. If you have flat bars you dont have to deal with all that. The Hy/Rd are cable actuated hydraulic, with the reservoir at the disc, so you dont need to replace any shifters or drive train parts.
I have no experience with Hy/Rd, but the Spyre also are dual piston activated. I converted from the BB7. In my experience the BB7 were almost as good in comparison. With the 200mm rotors used on tandems it takes very little force for the single piston deflect the disc slightly so that it contacts the pad on the other side, so the dual piston actuation does not yield major improvement in stopping power. I also did not have problems setting them up without rubbing, though the dual piston is easier to adjust.

My brake experiment is ongoing. I expect compressionless housing and the Ice Tech rotor for the rear any day in the mail. So far have been underwhelmed by the stopping power, but it is adequate. My main thing is heat dissipation as we ride a lot on long steep gravel descents.

Last edited by marciero; 07-25-16 at 05:28 AM.
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Old 07-25-16, 07:19 AM
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Originally Posted by mtseymour View Post
Welcome to the site! If the BB7 is not good enough for a 170lb rider on a single bike, why use it for a 300lb tandem team?

Still plenty of tandems out there using the bb7. You need to know how to use it to your advantage.
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Old 07-25-16, 08:19 AM
  #10  
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Originally Posted by mkane77g View Post
Still plenty of tandems out there using the bb7. You need to know how to use it to your advantage.
Glad that the BB7 works for you.

However, consider that the OP lives in mountainous Pacific Northwest, and has already encountered noise and warped rotors. No matter how well the BB7 is adjusted, its single piston design is prone to noise and overheating. This is why the the BB7 is unpopular for new single bikes (as OEM option or as an upgrade). It's only common on tandems because it's inexpensive, compatible with triple with road shifters, and adequate for rolling terrain.

The price difference between the BB7 and Hy/Rd is less than $75 per wheel (based on list price). It's far better to upgrade to the Hy/Rd than keep buying new pads and rotors for the BB7.
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Old 07-25-16, 12:38 PM
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Hmm... not sure how we connect heat/warping with an advantage of dual piston caliper? That one does not correlate for me.

I have BB7s with Hope 2 piece floating rotors. Yes the big rivets can be a problem with this combination and I have eliminated most of this by some careful modification of the caliper with a file. I still have just a slight tick on the front now and then.

We have done some decent grades with them and gotten them fairly hot. Coming down from Dante's View in Death Valley comes to mind. I do keep the speed down and alternate front/back use in these conditions. Got some color on the brake surfaces that day but no warping and good brakes all the way.

Biggest challenge I have had is trying to get the calipers adjusted with A) minimum pad to rotor clearance and B) no dragging. Toss in just a bit of rotor runout/wobble and this becomes very difficult. Too much pad clearance and you run out of lever travel before you get enough anti-go and not enough pad clearance and you get dragging and always on anti-go. This is the area where I would expect a caliper that moved both pads to excel over the BB7.

I do sometimes, but not always, get some squeal. I use it as a tool to announce my presence as I come up behind slower traffic

I think you read just a few horror stories about brakes on the 'net and it makes you paranoid. The BB7s may not be sexy nor the ultimate but they are functional.
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Old 07-25-16, 03:49 PM
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Originally Posted by mtseymour View Post
Glad that the BB7 works for you.

However, consider that the OP lives in mountainous Pacific Northwest, and has already encountered noise and warped rotors. No matter how well the BB7 is adjusted, its single piston design is prone to noise and overheating. This is why the the BB7 is unpopular for new single bikes (as OEM option or as an upgrade). It's only common on tandems because it's inexpensive, compatible with triple with road shifters, and adequate for rolling terrain.

The price difference between the BB7 and Hy/Rd is less than $75 per wheel (based on list price). It's far better to upgrade to the Hy/Rd than keep buying new pads and rotors for the BB7.
What advantage do you see with the HY/RD compared to the Spyre, which has the dual sided braking action without the complication of the hydraulics? Particularly as there are no finned pads that I know of available for the HY/RD, I would worry about heat dissipation.
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Old 07-25-16, 10:50 PM
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Originally Posted by vrooom3440 View Post
Hmm... not sure how we connect heat/warping with an advantage of dual piston caliper? That one does not correlate for me.

I have BB7s with Hope 2 piece floating rotors. Yes the big rivets can be a problem with this combination and I have eliminated most of this by some careful modification of the caliper with a file. I still have just a slight tick on the front now and then.

We have done some decent grades with them and gotten them fairly hot. Coming down from Dante's View in Death Valley comes to mind. I do keep the speed down and alternate front/back use in these conditions. Got some color on the brake surfaces that day but no warping and good brakes all the way.

Biggest challenge I have had is trying to get the calipers adjusted with A) minimum pad to rotor clearance and B) no dragging. Toss in just a bit of rotor runout/wobble and this becomes very difficult. Too much pad clearance and you run out of lever travel before you get enough anti-go and not enough pad clearance and you get dragging and always on anti-go. This is the area where I would expect a caliper that moved both pads to excel over the BB7.

I do sometimes, but not always, get some squeal. I use it as a tool to announce my presence as I come up behind slower traffic

I think you read just a few horror stories about brakes on the 'net and it makes you paranoid. The BB7s may not be sexy nor the ultimate but they are functional.
I never said that the BB7 was a horror story, or that it's not functional. It works fine for some riders but is not be the best option for teams who want to ride fast or make demanding descents.

As the single-piston design, the BB7 can't provide powerful braking. On a steep descent, this means that you have to brake earlier, and engage the brake for a longer time. The end result is a hotter caliper and rotor. With the Hy/Rd and R785, it's possible to brake less and still keep your speed under control. We've done many long and steep descent (8-12%) on century rides with no brake fade or hot rotors. We can't say the same for the BB7.

The BB7 caliper will also heat up faster because it has plastic parts. Consequently, some teams have gone to the Bengal MB700T for it's all-metal construction. The Hy/Rd and R785 stay even cooler because the hydraulic fluid provides additional heat dissipation.

Here are some reviews on the Hy/Rd:

First Ride: TRP's HY-RD Hydraulic Disc Brakes - Updated: Photo Gallery, Full Ride Impressions - Cyclocross Magazine - Cyclocross News, Races, Bikes, Photos, Videos

Review: TRP Hy/Rd mechanical interface hydraulic disc brakes | road.cc
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Old 07-25-16, 11:24 PM
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Originally Posted by bwebel View Post
What advantage do you see with the HY/RD compared to the Spyre, which has the dual sided braking action without the complication of the hydraulics? Particularly as there are no finned pads that I know of available for the HY/RD, I would worry about heat dissipation.
As a cable-actuated hydraulic brake, the Hy/Rd will be more powerful than the mechanical Spyre. The hydraulic design will simplify rather than complicate the setup or maintenance. The Hy/Rd is self-centering, and will automatically adjust for pad wear. The Hy/Rd works like the full hydraulic brake on my single bikes. I change the pads once per season and ask my LBS to bleed the fluid if needed. I don't have to fiddle with the pad to keep them quiet or adjust for wear. This is low maintenance!

The Shimano Ice-Tech finned pads are not necessary if you use a good 200mm rotor (eg. Shimano RT86). For teams using the R785 brakes, even 180mm rotors are big enough. The Hy/Rd and R785 are using proven technology from mtn biking. The Hy/Rd offers plenty of power, modulation, and heat dissipation. The R785 offers even better braking but you have to switch to hydraulic shifters (ST-R785 or ST-RS685).
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Old 07-26-16, 01:01 AM
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For what its worth, I was about to pull the trigger on a pair of HY/RD's at the LBS where we bought our new tandem. A mechanic there advised against them and recommended the Spyre model. We have Avid BB7's on the tandem in question. It came stock as a flat-bar road bike but I converted it to drop bar. I used Travel Agents to get around the difference in mechanical advantage of the flat-bar brake levers and the new ones. Now I have some money to get rid of that kludgy arrangement and get proper calipers that match road brake lever mechanical advantage.

I've bought the Spyre's but have not installed them yet. I have 160mm rotors F/R which was the stock set up but I have ordered 180mm rotors and adapters which have arrived but have not yet been picked up. The instruction sheet accompanying the Spyres talks extensively about how much heat is generated by the brakes in normal operation. Clearly the stock brake components expect and are designed to cope with significant amounts of heat. Spyres are half the price (and weight) of HY/RD's and I think represent enough of an upgrade over BB7's as I am prepared to invest in. I have some Ice Tech rotors on standby, but my experience with stock Avid rotors indicate that just by going up a size will give us plenty of performance increase. I have no plans to modify the calipers themselves.
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Old 07-26-16, 04:25 AM
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Originally Posted by Leisesturm View Post
For what its worth, I was about to pull the trigger on a pair of HY/RD's at the LBS where we bought our new tandem. A mechanic there advised against them and recommended the Spyre model.

...
We have Spyres and I really like them (though they are the only disc brakes I have ever ridden), though I do have a couple of complaints:
- I have not been able to adjust them so I can pull the rear brake lever tight without bottoming out while the pads don't rub when released. I,e, I don't feel I a getting the full possible stopping power.
- The TRP stock resin pads wore out after about 2000 miles and I now run swissstop sintered pads. With both, I find that I have to tweak the pad spacing every couple of hundred miles.

Both of these I would like resolve.

What reason(s) did your mechanic site as reason to favor the Spyre over the HY/RD's?
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Old 07-26-16, 06:20 AM
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Originally Posted by mtseymour View Post

The Shimano Ice-Tech finned pads are not necessary if you use a good 200mm rotor (eg. Shimano RT86). For teams using the R785 brakes, even 180mm rotors are big enough. The Hy/Rd and R785 are using proven technology from mtn biking. The Hy/Rd offers plenty of power, modulation, and heat dissipation. The R785 offers even better braking but you have to switch to hydraulic shifters (ST-R785 or ST-RS685).
You can say finned pads aren't necessary, but given the failure mode of hydraulics if they do overheat, I'd rather have every possible advantage when we are doing serious descents.

I haven't use the Shimano hydraulics, but I have used the SRAMs, and I was kind of underwhelmed. I had just as many, if not more, problems with squealing, rotor pinging and adjustment as I did with the cable brakes. I'm trying the SRAMs on another bike and really like the promise of hydraulics, but I can't say I see what the big deal is about them so far. I my try the HY/RDs as well, but, like another poster, I was warned off them by a local mechanic. He described them as kind of a kludge and suggesting either staying mechanical with the best quality housing or going full hydraulic.
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Old 07-26-16, 07:09 AM
  #18  
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This spring we purchased a new 2014 Speedster with the Spyres. these are our first experience with disc brakes and we've been pleased so far. They brake well and we have no noise beyond a little buzz with the front brake. We are still on the original pads with no adjustment yet. We are a heaver team and have done several 1 mile descents here in our area with no issues. I'm still a little nervous as I'm use to our other tandem which had V brakes and the drum drag brake as an option on one of our wheelsets. But all good thus far. As the OP has asked, I too and interested in what replacement pads and disc we should use when the time comes.
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Old 07-26-16, 09:21 AM
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Originally Posted by mtseymour View Post
I never said that the BB7 was a horror story, or that it's not functional. It works fine for some riders but is not be the best option for teams who want to ride fast or make demanding descents.

As the single-piston design, the BB7 can't provide powerful braking. On a steep descent, this means that you have to brake earlier, and engage the brake for a longer time. The end result is a hotter caliper and rotor. With the Hy/Rd and R785, it's possible to brake less and still keep your speed under control. We've done many long and steep descent (8-12%) on century rides with no brake fade or hot rotors. We can't say the same for the BB7.

The BB7 caliper will also heat up faster because it has plastic parts. Consequently, some teams have gone to the Bengal MB700T for it's all-metal construction. The Hy/Rd and R785 stay even cooler because the hydraulic fluid provides additional heat dissipation.
I've had the BB7's on our Tandem now since I bought it in 04. First just a rear because fronts weren't available. I've had no issues with them at all over the years. Never overheated them, included descents on very twisty 20+ percent grade roads and we are a 350+ pound team. We've even hit 70 mph descending Oakville Grade in Napa so I don't go slow either. Only thing I've changed were to Ice Tech rotors (203 front and back). I don't brake earlier or for a longer time - just the opposite - I brake harder and shorter - which results in much less heat. Just like I do in my race car.

What does this prove - nothing really other than everyone's experience isn't the same.
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Old 07-26-16, 02:20 PM
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Originally Posted by bikefriday View Post
My wife and I are loving our new Co-motion Mocha with the Avid BB7 mechanical disk brakes (200mm rotors, and metallic pads). However, on the hilly roads we are frequenting around our house, I find that the front rotor sometimes warps and then makes a rubbing sound after cooling. Not a significant drag on the wheel when spinning, but noisy. I've also tried straightening the rotor with my Park tool...but that's tough and time consuming.
My question to the group is...what options are there out there for improvements that might prevent this from happening? I've seen finned brake pads, larger rotors (203mm), different rotors (Hope, etc), floating rotors, and different pad materials. However, at this early stage in our Tandem life I don't have the experience to form an opinion, and wanted to poll others before making any purchases. Wondering what works for others, and what the groups opinions are?

Thanks in advance for any help with this.
Some questions: what exactly does "hilly" mean, i.e. vertical drop, duration of runout, elapsed time to next descent, etc. 200mm rotors are about as big as they get. Teams that used to need a drag brake find that they no longer do with 200mm rotors. Just asking, is it possible that you can experiment with different brake applications the way teams with rim brakes need to to avoid blow-outs. Is it possible to mount a rim brake (hydraulic?) and alternate between the rear disc and rear rim brakes?
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Old 07-26-16, 02:55 PM
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Originally Posted by Paul J View Post
This spring we purchased a new 2014 Speedster with the Spyres. these are our first experience with disc brakes and we've been pleased so far. They brake well and we have no noise beyond a little buzz with the front brake. We are still on the original pads with no adjustment yet. We are a heaver team and have done several 1 mile descents here in our area with no issues. I'm still a little nervous as I'm use to our other tandem which had V brakes and the drum drag brake as an option on one of our wheelsets. But all good thus far. As the OP has asked, I too and interested in what replacement pads and disc we should use when the time comes.
To be honest I don't quite remember exactly what his objections were but he had a few. It was enough for me that the Spyre's were quite a bit less expensive and much lighter to boot. With the BB7's, to set them up correctly you have to allow less clearance on one side of the rotor than the other, to allow the rotor to deform slightly from the pressure of the active brake pad. My eyes can no longer make those fine distinctions and I am anal enough to want it all exactly right. The double action nature of the HY/RD's appealed, and since the Spyre's are double action as well, makes them an easy sell, to me in any case. In a review of the Spyre's I read, the reviewer found adjusting the pads to be an issue. Their solution was to back both pad adjusters on each caliper out to their stops, and to use the master brake cable adjusters to compensate for pad wear. I haven't mounted the brakes yet so can't comment. Just passing it on.

Your rear brake issue sounds a lot like brake cable stiction. The caliper pad retraction springs on BB7's aren't that strong either. When I installed the inline Travel Agents to make my MTB BB7 calipers work with my Tektro road levers I found that there is so much drag introduced by the Travel Agents that the pads would no longer retract. At all. Even on the front brake! I was hoping the Spyre's would be better in that respect, but since they do not require Travel Agents to work the problem wasn't really on my radar. Rear brakes, especially on tandems, can have issues around cable drag. I am not completely surprised by your experiences. So... some things to try: invest in some new cable housing. Anything advertised as being "slick", "lubricated", "tefloned", etc.. You've saved a bunch by not buying full hydraulic brakes, blow some on hyper quality cable housing.

You might also upgrade the cable wires themselves to something advertised as being teflon coated, or otherwise 'well lubricated'. Are you using compression-less housing? It is what is recommended, as I understand it. I fashioned a pair of super powerful pad retraction springs of my own to work with the BB7's. At Home Depot I found some coil springs about 1/2" in diameter. They were about 4" long and I cut them to about 3" long. They resisted being compressed by design. I built in a fair amount of preload by cutting the spring longer than needed to fit in the space that is affected when the brake caliper arm is pulled towards the caliper body under braking action. The brake cable has to be disconnected and threaded through the coil spring. The spring is compressed to fit in between the caliper arm and the caliper body. It exerts a very powerful caliper arm return pressure which also increases the resistance felt at the brake levers. I quickly got used to the additional pressure.
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Old 07-26-16, 11:05 PM
  #22  
mtseymour
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Originally Posted by joe@vwvortex View Post
I've had the BB7's on our Tandem now since I bought it in 04. First just a rear because fronts weren't available. I've had no issues with them at all over the years. Never overheated them, included descents on very twisty 20+ percent grade roads and we are a 350+ pound team. We've even hit 70 mph descending Oakville Grade in Napa so I don't go slow either. Only thing I've changed were to Ice Tech rotors (203 front and back). I don't brake earlier or for a longer time - just the opposite - I brake harder and shorter - which results in much less heat. Just like I do in my race car.

What does this prove - nothing really other than everyone's experience isn't the same.
You're a skilled and brave team to hit 70mph on a tandem. Most of us are less skilled and prefer a lower speed limit. Even if we survive a 50mph+ descent, my stoker will kill me I suspect that this is a majority view because hydraulic brakes are ubiquitous on mtn bikes, and are the dominant choice for mid to high-end road bikes (Trek, Specialized, Cannondale, etc). The BB7 used to be only choice for tandems, but there are now better options. Every team has different priorities, but it's hard to dispute that the Hy/Rd and R785 offer stronger braking, more consistency, and less maintenance.
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Old 07-26-16, 11:14 PM
  #23  
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My 2nd set of pads for MY BB7 are Kool Stop Organic (but I'm a Single Guy) ..
@ LBS We got a MTB in with The red outside Knob warped from the Heat, generated ..

Yea Because it's Hydraulic the Hy Rd self adjusts for Pad Wear...

Demo Vid showed them Repeatedly 'lighting up' the disc to Glowing Dull Red and still didn't fade.. Bench Test.

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Old 07-27-16, 08:10 AM
  #24  
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Originally Posted by mtseymour View Post
You're a skilled and brave team to hit 70mph on a tandem. Most of us are less skilled and prefer a lower speed limit. Even if we survive a 50mph+ descent, my stoker will kill me I suspect that this is a majority view because hydraulic brakes are ubiquitous on mtn bikes, and are the dominant choice for mid to high-end road bikes (Trek, Specialized, Cannondale, etc). The BB7 used to be only choice for tandems, but there are now better options. Every team has different priorities, but it's hard to dispute that the Hy/Rd and R785 offer stronger braking, more consistency, and less maintenance.
I've been running disc brakes on my MTB since the first Avid's became available - long before hydraulic discs were readily available on MTB's. I'd argue that maintenance on a cable pull is easier - and bleeding - especially with the long run on a tandem can be a PITA as the rear on a MTB can sometimes be finicky. Hydraulics are also not immune to pad drag either.

Are they stronger - possibly - but I've not tried them because I have no need to fix what ain't broke. When we eventually buy a new tandem - they'll come in to consideration. However - as it stands now - there are no triple options and that just kills it for us. With the type of places we ride, steep inclines etc. and the fact that we don't like big jumps in gearing - I'm not inclined to look at double cranksets for the tandem with wide spaced rear clusters. It doesn't suite our riding style and locale.
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Old 07-27-16, 07:15 PM
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Originally Posted by joe@vwvortex View Post
I've been running disc brakes on my MTB since the first Avid's became available - long before hydraulic discs were readily available on MTB's. I'd argue that maintenance on a cable pull is easier - and bleeding - especially with the long run on a tandem can be a PITA as the rear on a MTB can sometimes be finicky. Hydraulics are also not immune to pad drag either.

Are they stronger - possibly - but I've not tried them because I have no need to fix what ain't broke. When we eventually buy a new tandem - they'll come in to consideration. However - as it stands now - there are no triple options and that just kills it for us. With the type of places we ride, steep inclines etc. and the fact that we don't like big jumps in gearing - I'm not inclined to look at double cranksets for the tandem with wide spaced rear clusters. It doesn't suite our riding style and locale.
Actually you can run a triple with hydraulics. I have a tandem set up with the "1x11" SRAM hydraulic levers and then run a triple front derailleur off of a bar end lever. Works quite well, better than most triple front STI shifting, I expect. Not sure if shimano offers a left hydraulic lever without the shift components. If you wanted to use bar ends for both shifters, TRP/Tektro makes a both left and right brake levers/disc calipers without any shifting components as well.
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