Accordion

I have a 2011 Novara Safari that is prepped for disc brakes. I can see from the front hub that there are six openings to accept the disc brake and I can also see that there are two holes on a mounting plate molded into the left side of the front fork.

I want to put a front disc brake on only. No rear needed. The front does 80% of the stopping anyway so this is the one I need.

I looked at some options - Avid Brakes....looks like I can get a plate and mechanism for $50.

My questions - what do the sizes mean? 160mm 170mm 185mm, etc. Can I use whatever I want on the Safari? What about mechanical versus hydraulic. I assume hydraulic uses some type of oil or water to apply the pressure whereas mechanical just means you squeeze the brake lever and it closes the brake.

Any help is appreciated. I'm pretty new at disc brakes!

Cyclesafe

Both work, but mechanicals can usually be repaired on the road and are preferred while touring for that reason. Rotors are available in various sizes; the bigger the better stopping power, but any would probably work OK. I have 203's, but for a 250 lb total load, they're overkill. Look at stock bikes to make your choice.

Cyclebum

Interesting that you say you want only front disc. I've pondered this option as being the most practical way to minimize rim wear without the weight and complications of disc for both wheels. There was a recent long discussion about that here.

As disc put more stress on the wheel, might be a negative if only on the front and used exclusively for most of the stopping. Don't know about that.

I concluded that for the type of touring I do, discs would needlessly complicate my life. But, if I were to head out
for remote areas, especially where rain and mud were common, like east Asia, I'd certainly give the combo you question serious consideration. Or, if I anticipated riding extensively in mountaneous areas with long, steep downhills.

sstorkel

160mm, 185mm, 210mm etc. are generally the diameter of the rotor. Larger rotors dissipate heat better and, in theory, provide more stopping power. They also exert more force on the forks, so there's usually a maximum size that the bike is designed to accept. My guess would be that the Safari is designed to use 160mm brake rotors.

Hydraulic brakes are generally regarded as having better modulation than mechanical disc brakes. They may also require less lever effort than a mechanical brake. The downsides to hydraulics (a.k.a. "hydros") are increased cost, possibility of damage (ex: a nick in the brake line can allow the fluid to drain out, rendering the brakes useless), and more complex maintenance. Mechanical disc brakes are generally cheaper than hydros, less likely to fail, and easier to maintain.

I've got Avid BB7 brakes on my touring and commuter bikes and Magura Marta hydros on my mountain bike. The Magura Martas are the best braking system I've ever used on a bicycle... and complete over-kill for anything other than mountain biking. BB7s are a nice upgrade over rim brakes, especially when it rains. Like all Avid brakes, they tend to make quite a bit of noise. On tour, I felt like I was tweaking the adjustment every couple of days to keep them from squealing. BB7s are cheap enough that I wouldn't consider buying the slightly less adjustable BB5s.

Accordion

Thank you very much for all the advice.

I see that PricePoint has some 2010 Avid BB7s for $44 in 160mm size. Those seem to be perfect for my needs.

Quick question: Can I use the stock brake lever and cables I have? I realize that I may need to get longer brake cables but with my understanding of mechanical brakes any lever should work fine.

Thanks again!

gorshkov

I've got a Raleigh Sojourn with BB5s (160mm front, 140mm rear), and I've been fairly happy with them, though I don't think that they significantly outperform cantis except in wet weather.

My two cents would be to put the same kind of brakes on front and rear. That way you only need to carry one set of spare pads.

You need to be careful of lever compatibility. MOST mechanical disks have the same cable pull as V-brakes, but Avid has started making versions of the BB5 and BB7 that use a shorter cable pull to make them compatible with standard road levers. If your bike has V-brakes now, you should get the standard brakes. If it has cantilevers now, you should get the road-compatible version.

NoReg

The set-up I was considering was the bb7 MTB front only with a 2 finger lever on the tops, and cantis all around opporated with road levers. So that would be three brakes total. The idea was:

1) improve the braking performance, having come back at the time from a long tour with lots of brake problems,

2) get levers on tops and drops, not a big deal but not bad either, like the cross levers.

3) Get more redundency for my near tandem loads. Tandems use three brakes.

I bought some of the parts, but never went through with it. I didn't want to compromise the ride of the front fork.

seeker333

PP is a good source for inexpensive parts. I've been buying from them for over a decade now, they've never disappointed me. The $45 160mm 2010 model is the one you want.

https://www.pricepoint.com/detail/187...t_Rer-2010.htm

The mtb BB7s are compatible with all mtb (mechanical, i.e. cable) levers, including your stock levers.

I didn't look, but odds are your fork will only accept the 160mm disc, which will work fine for your application. The curvature of the fork prevents larger diameters from having adequate clearance. You need a fork with straight legs (suspension) for the bigger discs.

You will need new housing and brake cable. Cutting and finishing conventional brake housing properly is a little complicated. You want to cut it cleanly without crushing it, then you have to file the end flat so it seats properly. Go to Park Tools and research this topic.

Jagwire ripcord aka Nashbar mech disc brake cable can be cut easily, with no filing required, due to it's kevlar construction (no steel). I buy it when it's on sale for ~5 bucks. I discovered this product several years ago, shortly after I perfected a procedure for cutting and filing conventional brake housing with common tools.

https://www.nashbar.com/bikes/Product...1_10000_202417

The new cable run may be a little tricky. Plastic tie straps might help.

PamolaPat

I upgraded to BB7s on the front end of my commuter and it has been totally worth it. I used the Jagwire product from Nashbar which seeker333 mentions. It's a great product and very worthwhile...the first time you ride in the rain you'll know it was worth it! I cut my cable housings with a Dremel tool using a carbide disc bit, which works perfectly. However, there are steel strands in this housing. Not a problem for the Dremel though.

sstorkel

+1 on using a Dremel to cut housing. I've got an expensive Park housing cutter and it invariably ends up crushing the housing. Results are somewhat better if you cut the housing with a piece of cable inserted at the end, but I think the Dremel still does a better job.

ollyisk

You may want to consider floating rotors for sanity's sake. I'm a bigger guy (I hover around 240ish) and I've had problems with rotors warping on me--I don't know if I was just laying my bike down on the rotors and them bending, or if they were overheating and warping, but I haven't changed my bike handling behavior, and I haven't had any issues since I upgraded to floating rotors. Typically speaking, floating rotors are lighter than regular rotors and more heat resistant (the inner spider is usually aluminum). However, they're also quite a bit more expensive.

I frequently had to adjust my brakes when I had the stock Avid rotors--I was constantly bending the rotor back into shape, or turning the dials on the caliper to get it so the rotor wasn't rubbing. Since I upgraded to Hope's Floating rotors, I've never had any issues with my rotor warping or rubbing on the brake pad, to me they were worth the $45/each (or whatever they're going for), because truing a disc rotor can be an f'ing nightmarish task if you don't know exactly what you're doing.

Accordion

Really appreciate all the advice.

My main reason for wanting to go disc on the front is the stock Safari V-brakes are really spongy to me. I'm used to my CAAD9 brakes and they are rock-solid.

I've adjusted these brakes from here to Kingdom Come and I'm tired of the spongy feeling still. I think it's the nature of the brakes - they are cheap.

Since this will be a commuter-type mini-tour bike I thought discs would be good but the stories above about constant adjustments with the Avid brakes are scaring me. The last thing I want it warped rotors or constant adjustments. I can't just purchase the same brakes my CAAD9 has because my Safari isn't drilled for them plus the fact that under load they may not be so great. I'm 190 and my CAAD9 is 17 pounds. My Safari with rack and rackbag is around 35 pounds!

Seattle Forrest

I love my disc brakes. They don't have any more power than the rim-pinchers on my road bike, under the best of conditions, but when it starts to rain sideways, the consistency of stopping power is really nice. You don't need to "wipe them down" or anything like that; you pull the lever, and the bike comes to a stop.

But you should seriously consider getting one for the rear wheel, too. I've noticed that the rear brake supplies more stopping power when I'm carrying a lot of heavy stuff in the panniers.

I have Avid BB7s on my cross bike. I need to adjust them more often than I think I should, but on the other hand, it takes about 20 to 30 seconds to adjust them on either wheel. Knock on wood, I've never had any mechanical problem with them.

ollyisk

Don't be worried about adjustment! It's really not that hard.

There are lots of tutorials on "pain free disc brake adjustment" on the net, but I'm an idiot and didn't really bother to look around when I first got them. I had an epiphany one day and suddenly "got it." It hasn't been so bad since then, and I've honestly never even had to touch my brakes since I put the floating rotors on.

I used Ashima and Avid rotors before switching to Hope rotors (again, the Hopes are considerably more expensive). My experiences were like this: the Avids got bent out of shape rather quickly, but never too bad. I had to adjust my brake pads so I had very little braking power. I could never really tune them to the point where I felt confident with them. After that, I bought Ashima rotors because I thought sawblade rotors looked "cool," and they were really lightweight (and quite cheap). They came bent from shipping, and I could never get them right. It just got worse and worse, and one night after trying to true and tune them for an hour, I freaked out and just bent the hell out of them in a fit of adjustment rage. I got the hope rotors, and they've been perfect absolutely since day one. I haven't even had to use my disc truing fork once to prevent rubbing.

To be fair though, lots of people use Avid and Ashima rotors and claim to not have issues. My personal experience wasn't so sweet. Paying $90 for two rotors that have essentially been maintenance free since day 1 is absolutely the price of admission for me.

Don't skimp on rotors--if they're cheap, there's a reason for it.

sstorkel

Agree with this. My Avid BB7 rotors always seem to be slightly tweaked, which does compromise stopping power a bit. Not enough to be a huge issue, but it does contribute to their endless scraping and squealing...

fietsbob

I'd reccomend the pairing of Front and rear discs ..
True , weight G shifts forward, when braking, to a stop.

but a lot of rear rims wear thin from speed control , without coming to a full stop,
dragging the rear brake on the rim..

Galfer discs are thicker than Avids, but cost significantly more ..

Its particularly true when the rear hub is using a 4 bolt disc.

positron

I use avid BB7 (road version) with tektro aero levers. Ive never had an issue with bent rotors (on my touring bike, but I used to bend rotors on the MTB on occaision)

I also nearly never adjust the brakes. maybe once every two months i click the pads in one click. if that.

highly recommended for the ~75 bucks it cost for the set.

marmot

I have BB7s on my main bike, and they are notably quiet. They make a barely perceptable whispery hiss, and occasionally a very quiet "moan" just as the stop is completed. They only have a couple hundred miles on them, though, but so far there's no hint of scraping or squealing. They are MUCH quieter than the rim brakes on my other bike, and far more effective.

sstorkel

Just wait! Eventually, you'll drop the bike and bend the brake rotor ever so slightly, or the pads will get a bit glazed, or the calipers will go out of alignment and then you'll be treated to the scraping, squeaking, squealing, and turkey warbling that seems endemic to Avid brake products...

NoReg

I don't know if it is an issue, but I found some old Jobst thread and he mentioned that front wheels are more likely to collapse than rear ones. He was saying how the old idea of using 40 in the rear and 32 in the front was all backwards as almost all wheel collapses are in the front wheel. Which does raise the point of whether the front wheel dish is a good idea.