Disc Brake Bikes - What to Consider Before Purchasing

Not related to disc brakes, but if you'll want to fly with your bike in a hard case, bear in mind that integrated cable/hose routing (through the head tube) can make it difficult or impossible to get your bike into a standard hard case.

I’d choose hydraulic over mechanical or rim any day. Also, I’d keep away from most SRAM disc brakes due to D.O.T. fluid. It’s highly corrosive, and very dangerous if it gets on skin.

Wheel life span is a big plus for disc, once service correctly etc your wheels should last alot longer than rims. I’ve a set of Mavics now 3 years old that roll like new with a yearly service , no fear of brake track wearing out.

 "I've never had wheel rim wear issues"

@ Paddigol

I'm curious about how you managed that. Do you do very little mileage or only go out in dry weather? The main reason I have to replace wheels is due to rim wear. I've been on several group rides where another rider's rim has blown - the most recent being just last week.

I'm fastidious about cleaning my bike - wheels, rims and brake blocks/ pads included - during the winter especially. I'm pretty light on the brakes too. Winter/ commuter bike has been Zondas for about 8 years (first wheelset written off in a crash with a van about 4 years ago). Mileage would be mixed - not crazy high but not low either. I've carbon rims on the other bike - will see how they fare over time.

I've nothing to base this on, but my suspicion re blowouts is poor maintenance or (and/ or) heavy brake use?

Or maybe its just been pure luck on my part.

I've got 40k km out of a set of rims before having to rebuild.

If you ride solo are light on brakes and keep rims clean they will last a long time.

Ride in wet weather a lot with mudguards and don't clean and a blowout is in your future.

I wore the rims of a cx bike gravel in under 3k km.

Fair point. I've been on the lighter end of the scale for most of my years... sliding up the scales now though! Love the hills, but I'm a fluid enough descender.

Anyway, its each to their own. If disc brakes make someone more confident on a bike, that can only be a good thing.

I dunno what yiz are all doing going around braking everywhere! :)

When I go for my spin I brake half way around for the coffee stop and then I pull the brakes again pulling in home. Like lads above, I've never worn out a set of rims. I've a set of mavic slr's that are 12 years old now, ok they haven't had 12 years non-stop use, but they've seen plenty of miles and the rims are fine.

Also, on the braking performance. Yes discs are better in the wet, but that's not to say rims are awful. They world has decades of cycling history on rim brakes and we didn't all go around crashing into walls because of poor braking ability.

I'm kind of intrigued myself, having bought a disc braked winter trainer for myself and used it exclusively all winter, to see how I view the change over to a rim braked summer/race bike in a few months time. But, just as changing to disc brakes wasn't transformative for me, I doubt changing back to rims will be catastrophic either.

What to consider? - Well it all depends on the bike. A top shelf rim bike will beat the pants off a mid-tier disc bike and vice versa. Rim bikes still have the advantage though in terms of purchase cost - second hand at least you can buy a bona fide pro level superbike in rim guise for the cost of a mid to lower end disc braked bike.

Regardless of how light you are or how lightly you apply the brakes, rims will wear out eventually. In my view, the wear indicators are very conservative and if you were to replace your wheels once the indicators had disappeared, i would be replacing wheel twice as often as i currently do!

I have a set of Zondas and and the rim on the rear wheel is concave in shape (wear indicators wore away over a year ago) I've a new set on order as i don't want to wait until the rim actually fails.

So you don't slow down/stop when approaching red lights, junctions, sharp bends, steep technical descents, heavy traffic, school wardens etc.?

Regarding the other comments about being fastidious with cleaning preventing rim wear, that doesn't make any sense to me as the bike will get very dirty within minutes in some conditions. No matter how fussy you are, if you do a 12 hour ride on a sh!tty day, the bike is going to be dirty for 99% of the ride. I seriously doubt that anyone cleans on the go.

As I said, I don't really care about the rim v disc debate. I'd just like to be able to buy rim versions rather than be forced down the disc route. I've given up hoping on that front though. Someone mentioned wheel degeneration (of course all parts wear out eventually, and by their nature rim brakes will wear a wheel out faster, but then everything is relative...) and I simply noted that it had never been an issue for me. Someone then wondered why, and I simply suggested that maybe it was to do with keeping my rims well cleaned and maintained. Whatever about the rim v disc debate, I've even less interest in debating what effect a well maintained and cleaned wheelset will have on lifespan 😄

I think we're in danger of veering off topic at this stage, so apologies to the OP!

Good pads and clean rims with well adjusted calipers give very good braking.

Irrespective of technology most cyclist would benefit greatly from

1. Improving braking technique

2. Learning to descend better

3. Learn how to anticipate when you'll need to brake.

If an average cyclist did all that they would gain more than any gear upgrade after giving someone 23 digits

Quality brake pads for sure a brilliant upgrade from the stock Shimano pads.

Don't last anywhere near as long though (as you'd expect).

Again, not my experience with properly set up, mid-to-high end rim brakes. Take my Campy Chorus on carbon rims - they're set up so minimal clearance between pads and rims... and pads are sufficiently good that relatively little force is needed to achieve braking power. As with everything, you can have great kit but if it's not set up properly you're not going to get the benefit of it. The hydro disc brakes on my CX bike need recalibration as they're way too spongy now after a couple of seasons' use.

Nothing worse than the feeling of crap rim brakes in the wet on a descent, granted. Heart-in-mouth stuff!

....and red hot wheels from excessive braking.

Not everyone does 30k kms a year and is suitably conditioned. There is a definite difference in fatigue in wrists and arms when switching from rim brake to hydraulic.

If getting discs - If at all possible go for hydraulic disc. Mechanical disc can very often be difficult to keep from rubbing. I had a couple of bikes with mechanical discs and it felt like I was nearly constantly having to fiddle with them.

I have had a few CX bikes - both SRAM and Shimano hydraulic disc and the mineral oil shimano set up is much simpler and nicer to work on. 2 bikes with SRAM rival hydraulic fitted have had leaking nasty DOT5.1 from a brake lever.

It's like stepping into a thread from +20 years ago on a MTB forum...

The only mechanical discs that are consistently rated are BB7s, but you can get hydros (which self adjust clearance) at the same cost so why wouldn't you?