what is the difference between BB7 road and BB7 mountain? some mechanical leverage? LBS installed road BB7s on my mountain bike. will not work right. help

I hope all the lbs apologists see this one....

Yes, it's a mech leverage thing. Road BB7s are designed for short-pull levers--- road levers, bmx levers, canti-levers. MTB BB7s are designed for long-pull levers, such as (obviously) mtb levers designed for linear-pull brakes ("v-brakes") or the typical cable-actuated discs.

Your LBS owes you some standard BB7s and an install. Don't settle for less. Crooks like that oughta face criminal charges.

Does your MtB have the older/traditional canti brakes? If so then they matched the cable pull specs. to the levers that work with the cantis (and not the current long pull brakes and levers). Also many think that disk brakes should have stronger initial power, being described as more better. But disks have less initial bite, especially if they have not been bedded in properly. They only excel in conditions that rim brakes suffer in. But if your LBS did miss choose the calipers then they do owe you an explanation and the correction. Andy.

Let's think this through, Andy: does it seem likely that the OP's mtb came equipped with cantis and disc tabs?

They screwed up. They're either incompetent or unscrupulous. They need to make this right for the OP, and then he needs to find a new shop.

the brake lever must match the caliper

surreal- Many of my replies here are not so much for the OPs but for the others reading and trying to learn about their bikes. I agree that the likelihood of cantis and disk mounts is slim, but after 40 years of wrenching i have seen more then a few combos that one would never expect to see. Our local bike recycling efforts have produced some real strange combos. I've also had customers come in with their at home self done attempts to fix bikes using their old bike as a donor. I did agree that if the OP's set up is miss matched then their LBS needs to BOTH explain why (this is so the LBS learns not to do this again) and then make right. Andy.

update. the lbs realized what a major screwup this was and will make it right at no cost to me. still do not understand how they let this happen.

It's unfortunate that Avid uses the same model number for two very different brake sets. I wouldn't be surprised if the LBS just ordered a set of "Avid BB7" brakes, got sent the wrong type and didn't realize it.

I can see very easily how the road calipers could be installed mistakenly. The boxes (road and MtB) are identical but for a small label difference. The supplier part numbers (if the brakes were special ordered) are often virtually the same and often are adjacent to each other. It's a simple oversight to pull (or pick) the wrong one off the shelf (or into the on line cart). Often the person who picks the box is not the mechanic that installs the caliper. And until the new SL version of the BB7 came out the calipers look the same out of the box.

But what I have trouble with is that the mechanic didn't notice the lever/pad action was other then usual and that the stopping power was almost non existent. The QC part of the service loop went awal. I bet the mechanic or service manager didn't do any pad bedding in during the test ride. I wonder if a test ride was even done.

This is why I said that the LBS needed to explain how this happened. Not so much for the OP to learn why BUT MORE for the next customer to not have the same mistake happen. The shop needs to have a better check and balance system for the repairs done.

Perhaps the work was done "on the spot" while the OP was waiting. Perhaps the shop was very busy. Perhaps the mechanic was distracted. Perhaps the wrench was not experienced with disk brakes. But the shop needs to have a QC in place to confirm the end results of their service.

This is one of the reasons that i have always not liked doing service work while the customer is waiting. It sets up a expectation or standard of the amount of time the service takes (being what makes the service "good") instead of the quality of the work done. Of course some service (like flats) need to be able to be done ASAP. But the more involved work is usually better when their's no customer looking over the shoulder or pacing around the shop.

I don't know if my comments were what was going on in this case. But I wouldn't be surprised if some combo of the above was involved. Andy.

Surreal; So an LBS drops the ball and installs a nearly identical but wrong part = "Crooks like that oughta face criminal charges."

Really what part of reality does your universe spin in? I would guess yours is a universe of one idiot and a keyboard!

Geez!

B flat 7th?, Maj Or minor?

NB, SRAM has a parts breakdown .. See: in the caliper is a crown like ring with a series of ramps , in the edge.

that is what turns the rotation of the arm into the sideways motion that moves the brake pad to the disc.

the slope of the ramp is steeper to move the pad further , for the shorter swing of the road , short cable pull.

Classy. You should probably review the guidelines for this forum.

The OP's LBS stole the OP's money and negligently put him on a bike without functional brakes. Theft is a crime, and there's a lot of room for litigation in this situation....

What universe do you live in, where theft is legal and there's nothing wrong with endangering someone's life whilst charging them for it?

Understood; that totally makes sense. There's been many times where archived threads have contained the answers I was looking for, and there's been plenty of archived threads that present more questions than the answer.........

the bike is a 2013 GT Zaskar. i wanted to change the hydraulic disc brake system to BB7s mechanical. the LBS had the bike for about a week. i told the mechanic there was no hurry

Jesus...calm down. They made a mistake and are going to fix it. Don't you ever make mista...nevermind. I'm sure you do, then prosecute yourself to the fullest extent of the law or file suit against yourself.

Then there are times that brake systems work splendidly well with the wrong levers. case in point, when I was a dealer, I received shipment of a half dozen bikes with Shimamo cable operated discs, and short travel levers. Very shortly afterward, the OEM initiated a campaign to ship long travel levers for all the bikes in question. (2008 Brodie Ocho.)
Thing is, I had not even noticed, and even remember remarking how nice the brakes were after test riding. I had already sold a couple of the bikes, so I recalled them for a retrofit. To this day, years after closing my shop, I am doing annual service on one of these bikes, and the owner declined the retrofit at the time, being entirely satisfied with the performance. I test ride it every time, and they still work great.

I never suggested that the LBS should press charges or sue themselves, but they might as well be suing themselves, with a bonehead move like that. In these litigious times, it's incredibly foolish to charge someone for new brakes, installed, that don't function properly.

The fact is, they didn't make a mistake. They (presumably) ordered the wrong parts, failed to notice the error while unpacking the parts, failed to notice that they couldn't get the braking right, and neglected to test-ride the bike post-repair. That's, like, 4 mistakes. None of which they noticed until after the customer came back and complained. They're going to fix it? That's great. But, they dropped the ball pretty hard here, imho.

In my LBS-drone days, we were pretty sloppy, and mistakes were made. But, we had standards. We conducted testrides on each repair before we declared it "finished". We weren't going to take someone's money and put them on a bike without brakes.

respectfully,
rob

ps- we call them brifters b/c they are stupid

The first line of this reply shows just how overly serious you are about this. I was obviously joking...get it? I replied like I did because in your first post you all but accused the shop of putting the wrong brakes on the OP's bike on purpose, which is ridiculous. No one died, I'm pretty sure the brakes would have at least slowed the OP down a little if he had actually ridden them, and now the shop is readily admitting their mistake and taking care of it. Yes, the whole thing should not have happened. But not everyone gets everything right all the time. Maybe this shop doesn't do much work like this...maybe there was a disconnect in the ordering process...who knows? It will be fixed and the OP will be taken care of.

FWIW , a customer succeeded in downhill-ing hard enough heat the disc & to Melt
the big red knob that adjusts the stationary pad.

do keep your common sense cells in your brain engaged, on the Bike .. nothing is perfect.

Yeah, I understand that you're joking, and I apologize for seeming overly serious, but the bottom line is: this shop dropped the ball, and feeble excuses shan't change that. If the shop doesn't do much work like this, then how do they feel comfortable charging for repairs at all? Do they charge an amateur mechanics' rate?

I can totally understand how someone may've ordered the wrong part-- that happens. But how do we go from ordering the wrong part, to not noticing the error, to not noticing that it doesn't work properly on the stand, to not test-riding the repair, to taking the customer's money and letting him leave with dysfunctional brakes? If this were a thread about "the shop ordered the wrong part....", I'd still be scoffing at that lbs, in a far less serious way. But this is a thread about "the shop ordered the wrong part, installed it, somehow didn't know or didn't care about the repercussions, and took a customer's money and sent them on their way without good brakes."

Maybe I am being overly serious, but I seem to recall many of you getting really serious when ppl post about a DIY wrench-job going wrong or trouble assembling a bikesdirect purchase. "You should've gone to your LBS; that would avoid these problems." Or, when ppl complain about paying a massive upcharge if they patronize their LBS, some of y'all get real serious about "the LBS can do no wrong, and that upcharge is in place to keep the infallible LBS running." Let this be yet another reminder that, sometimes, the lbs overcharges you for the wrong part, and then overcharges you for the pointless labor it took to install that wrong part.

If the OP would oblige, I'd love to know how much he was charged for the road bb7 brakes, plus install... That should be about as funny a joke as we'll see on this thread.

The more I think about it, the more I see your point. I'm sure they didn't do it on purpose, but they definitely display much in the way of competence by letting the bike out of the shop like that. We'll never know what the brakes felt like, whether they were merely 'not good' or 'truly horrific', regardless the shop should have had at least some clue that things weren't going right.

MTB levers with 'road' calipers - that would be like using V-brake levers with cantis. Feels amazing in the stand, offers a lot less braking power unless you're a gorilla. I wonder how bad it was.

Bottom line, completely inexcusable that a bike left the shop that way.