TT/triathlon bike: disc or no disc

So… Should I get disk brakes or not?

I have heard they are a pain in the butt to work with, but at the end it seems the world is moving to that direction.

I love the trek speed concept, but for that money a canyon speedmax seems like a better bang for the buck…

Any suggestions?

I also like the a2 phreak, but seems to be slow accelerating and yet 2k cheaper with wheel brakes.

The primer bike seems a great bag for the buck, but I’m would need to get xs according to the emails and measurements I took. The xs have 650 wheels and idk if I want that

I have a speed concept and am not going to be upgrading for years

but… if I was buying a future bike I would go disk brake - more future proof - resale etc.

They are not hard to work on - usually the stories are about bleeding brakes or rotors that get banged up. The screeching is real.

EDIT - interchanging wheels is a consideration as well - I have one bike that will be rim brake with its wheels when all my other bikes will be disk brake and their wheels - can’t swap race wheel around as easily if they were all on the same braking method.


I bought my TT bike about the time discs were becoming common and my road bike well after discs were common in the peleton. Both are rim brakes, (v and caliper) I bought them because I know where I am with rim brakes. For the TT bike I’m never going to TT in the inclement weather that would call for discs. Id rather have something thats lighter and easier to adjust. Besides you don’t want to be braking to much on a TT bike anyway :wink:


One vote from me for the SC. I’ve had one for 3 seasons now, and love it. So choice. If my marriage falls apart, I’m going to identify as a bike, and marry my Trek.

WRT rim brakes, if you use brakes more than once during a triathlon, you’re doing it wrong.


I try to avoid the “which is better” question when it comes to brakes. I have bikes with both and yeah, IMO disks are better, but not leaps and bounds, and a rim brake is not a deal breaker. So with that in mind, I would get the one that you can afford, that fits, that makes you want to ride it, etc.

In the future, we will probably all have to move to disk brakes but I think that’s still a pretty distant future.


I have an SC with rim brakes, and disc brakes on my road bike. Personally, I hate the hassle of the disc brakes (but love having everything internal). I am a heavy sweater so I am constantly have issues with corrosion of the disc brakes and the flimsy pin that Shimano uses for the calipers. My road bike is in the shop at least every few months due to the brakes (admittedly I’m not the most mechanically inclined person).

With that being said, disc brakes certainly perform better with stopping, so if you do courses for triathlon or TT that require high performance braking at the last minute, then maybe look that route.

Lastly, the market has clearly shifted towards disc brakes. If you buy a bike right now that doesn’t have the wheels you want, you probably can find a could set of second hand wheels. However, I wonder how the secondary market will look 5 years from now.

Just my 2cents. Personally, if it is a bike you plan on having for awhile, I’d go rim brakes.

For me it was the ability to interchange wheels so I went disc brakes.

My 303’s for training on both bikes, and enve 7.8’s for half Ironman, or for a specia bunch ride :slight_smile:

If you’re putting money into new wheel sets disc is really the only option in my view.

Don’t worry about the aero difference or maintenance differences, once you get used to them they aren’t hard to work on. You can always avoid hydraulic and stay with cable if you really want to, even with disc.

Your TT bikes have brakes on them? Why?

Snark aside, buying new might as well get into the Disc ecosystem and save youself the headache of making the wheel transition at some point. But unless you’re doing TTs or Triathlons with gnarly descents and potentially in poor weather, rim is perfectly fine. People have been using rim brakes for a long long time.

I only have a half vote because I don’t own a road bike // tt bike with discs yet, but: disc. I guess we all have our own priorities and preferences, but man I hate how carbon rim wheels stop, let alone in the wet. It’s downright terrible. For me, it comes down to: If I have a bike that I feel comfortable riding outside of race environments (in training, on the roads) in a variety of conditions, I’m more likely to do it. I only take my TT out in race config on days where I know I can ride far away from other people, in low-traffic situations where emergency stopping is much less likely, that sort of thing. I also never take it out in the rain unless I absolutely have to or for practice. All of that is alleviated with disc brakes. I’ve got discs on my MTB and they’re great. Yes, you occasionally need to bleed them, etc, just like you have to do maintenance with any other part of a bike. No doubt, oil is messier than a cable. I think if I lived somewhere with great riding and great weather, my opinion might be a little different. But I live in a wet area with riding that is already a bit sketchy on a TT bike, and poor brakes makes that even worse. That’s just my preferences mixed with my environment, though, so these aren’t absolutes.

Like I said, only a half vote because I haven’t had to live with discs long term on a road bike, but for me: carbon rim brakes are basically my least favorite thing about my TT bike, and this fixes that. I can deal with some different maintenance behavior.

1 Like

Disc brakes are awesome

Because we train on our TT bikes, because there are hills, there are turns, we don’t race on closed courses, because there are other riders around us at times…:stuck_out_tongue_winking_eye:

As to the question, as I have said before, if you are going to ride the snot out of the bike for a long time, get rim brakes. Lighter and more aero. However, if you like to flip your bikes regularly, or have any desire to share wheelsets with your road bike, get discs.


I got a P5 disc after having this same debate. Bike is sweet. Rips corners like a road bike. Still stops like a boat, even with the discs. There are probably worse ways to spend far too much money on a toy.

If you ride Disc brakes and like them, do the same on the TT bike. If you don‘t like them or have no/ don‘t plan on having other disc bikes, you are good to go with rim.
It will not be a game changer either way.
I like discs, so I have it on all my bikes. Bad weather were I live.

If you are buying new, then yes, disc. If you are buying used, you might get a good deal on a rim brake bike. I think we are past the peak in the rim-to-disc brake transition, and investing in a new rim brake bike now makes little sense.

That’s a wild exaggeration. It’s just that you will have to learn new maintenance procedures, and once you got your head around, IMHO it is a net win. There are some things you will have to do with disc brakes that you won’t with rim brakes, and vice versa. You will never ever have to worry about cable wear and cables being bent inside that intricately shaped TT bike frame. Disc brake pads auto adjust to compensate for wear. Bleeding brakes, the thing that seems to terrify some rim brake owners, is either something your bike shop does during the yearly check-up. Or something that you can do yourself. I learnt it last year with the help of some youtube videos. It was absolutely trivial to do.

Plus, once you get used to braking with substantially less force and in all conditions, you don’t want to go back. Moreover, you can train on your race wheels since rims are no longer a wear item. (Unless you use sturdier tires on your training wheels.)

If you don’t use your brakes much, you can go even longer between maintenance intervals. My mom has hydraulic rim brakes on her bike (yes, those exist and are much, much better than cable-operated rim brakes). She didn’t need to bleed her brakes once in 10 years. Yes, she only used to commute to work with it, 2 km each way, but she literally did zero maintenance. (My brother and I checked her bike every now and then.)

1 Like

Because even if you compete, most of the time you spend training and have to compete with traffic, rain, bad road conditions and the like. The “people have been fine using rim brakes” is just a non-sensical. Reminds me of early copies of Moser Bike Guides(*) where you see the man himself on a rim braked mountain bike do things most people would struggle with on a modern bike. Thing is, modern bikes make that easier and safer for a larger number of people — and that includes disc brakes on TT bikes. Even if you only ride on relatively flat terrain, you’ll still have to deal with cars and the like.

(*) This is an early mountain bike guide book with routes in Germany, Austria, Italy and perhaps a few other countries. I used them 20 years ago before GPSes were widely available, and at the time it was very, very famous…

I haven’t ridden with carbon rim brake rims, but I frequently ride with people who do. There is also another point here, and that is noise. My buddy’s Enve’s brake tracks sing when he brakes and by the pitch I can estimate his speed. But it isn’t exactly a pleasant sound, not better or worse than when disc brakes squeal in my opinion (which sometimes happens when I ride in the rain).


The answer is always yes to the disc for the tri/TT bike! Wait… Wrong kind of disc. :joy::+1:


As for being future proof…

Do you really expect that rim brake wheels won’t be available within the expected life of this bike?

As a guy who likes downhill mountain bike riding, I appreciate disc brakes very much. I’m transitioning to discs if/when I get a new roadie (gravel and both MTB are discs). But for TT, do you really need it? Which do you want more? I would go with what you want on the TT.

The switch could happen quickly for new equipment. My aging mountain bike is the last 26” Mohican and even 4-5 years ago I’d have issues get the tires I want, etc. Modern drop bar wheel set s (= wide, deep, tubeless-ready) are for the most part disc-only.

I’m not a TT guy (although my power profile, particularly when /kg, says otherwise), I’d say get the one with dozens of really nice used race wheel sets available on the used market right now. You can find a lot more used carbon rim-brake wheels now than you could three years ago.

This all presumes you’re not often racing or training at the limits in wet weather.

@OreoCookie but think of all the aero carbon rim brake rims that will be coming onto the used market in the next 5 years.


Just got a new Tri bike and decided to go with rim. Far lighter and availability of race wheels I owned made a difference. I also work in a shop and while other seem to feel differently, the constant stream of disc brake bikes in for adjustment, squealing and general rub convinced me to wait a couple of years. Our mechanics have even started to side with me, as we see different thru axles, pitch differences, rotor size differences, fork flexing creating rub and general rub in many of them. I decided to wait until they standardize rotor size, thru axle pitch and size, bleed ports, and make the tolerances so that it will more likely accommodate a different wheel in case of emergency. Argon18 seems to have done a good job of incorporating the calipers into the fork in their new, yet to be released E-119, and I feel others will follow. Truth be told, I don’t want to have the bike that is the transition of test unit for the future ones that will have the issues solved better. Get rim for now, be lighter, more compatible with existing awesome wheels and let the manufacturers sort out the issues and standardize before yo become their “test dummy”.