Technical Updates

 

Tubeless tires are a Pain in the Ass

So why does anyone use them? Because there are benefits of course, but the drawbacks aren’t talked about very much. My experience has been that you get fewer flats with tubeless, but when you get one that can’t seal or be plugged it’s a huge pain in the ass.

First of all sealant is MESSY. It’s a complete pain to deal with. Setting up a new tire in a properly equipped shop is generally not horrible, but fixing a flat on the road can be a nightmare. Any time you have to take the tire off you’re dealing with sealant getting all over everything, mostly your hands and perfectly waxed chain. And it’s not just a flat that the tire needs to come off for; sometimes you need to remove the tire to fix a broken spoke. With tubeless that simple job is turned into an adventure of the sealant mess, pulling tape off the rim, thoroughly cleaning it and re-taping, and setting the tire back up again.

The other part is that tubeless turns your bike into a project. Sealant dries out, so it needs to be maintained. Top-up the fluid every few months, and don’t let your tires sit in the same position for too long or you’ll find horribly unbalanced wheels from a dried puddle of sealant in there. And then there’s the valve – they tend to get clogged so need to be cleaned once in a while, and the seal at the rim bed will eventually wear out, so the valve needs to be replaced, so now you’re pulling the tire and... well you get the idea.

So is tubeless the greatest thing since the quick-release skewer? If minimizing flats is your biggest concern and you’re OK with all the maintenance, then go for it... just be aware of what you signed up for!

Disc brakes are the best thing since the quick release skewer

After they’re broken-in and adjusted properly that is, but setup and maintenance can be anything from ‘no sweat’ to an hours-long ordeal. The fundamental issue is that the tolerances are very tight, so everything has to be adjusted perfectly… and even then it’s easy to screw them up.

Let’s start at the beginning and go through living with disc brakes…

Like I said the tolerances are very tight, so all of the components have to be perfect to start out with. Mounting surfaces not exactly flat and perpendicular to the dropout? Rotor runout more than 0.00nothing? Sticky piston? Internal hose routing pulls on the caliper? Welcome to disc brake setup hell.

But that’s all the mechanic’s problem. Now they’re set up and I’ll live happily ever after, right? Ha! Not so fast compadre. There’s a break-in period… two actually. The first is ‘bedding-in’, a good mechanic will do it for you, but if your brand-new brakes don’t stop very well they probably weren’t bedded-in. No big deal, unless the first thing you do is bomb down a hill expecting to stop at the bottom. The second break-in period takes a while, and is basically the pads and rotor getting to know each other, intimately. Might take 10 braking cycles, might take 40, but after this and possibly a readjustment you should be good to go for at least one more ride.

Now that they’ve been set up perfectly, broken in, re-adjusted, and ridden for a few hundred miles with no problems, what could possibly go wrong? Oh the innocence of youth… want to do something simple like take your front wheel off to put your bike in the car and go meet your buddies for a nice Saturday morning ride? No problem, just:

• DO NOT pull the brake lever with the wheel out! Unless you’ve put a spacer between the pads, this will push the pads together which will, in order of headache-grade: reduce lever travel and cause rubbing; push the pads together so you can’t put the wheel in; or push a piston out which you will definitely know because there’s brake fluid all over the place

• DO NOT let anything touch the rotor or even look at it wrong, lest it get even so slightly bent and cause rubbing

• DO NOT let any foreign substance touch the rotor lest it become contaminated, start squealing like a stuck pig, and need to be replaced along with the pads… that will be $60-$140 just for parts please. Here is the complete list of substances that will not cause contamination: 1) air; 2) water.

• Try to keep the bike upright, i.e. don’t lay it down in your trunk, lest air run from the reservoir into the line and make your brakes squishy as pea soup

• And if you’ve avoided all those pitfalls, when you remount your wheel, be sure to have the bike resting upright on the ground when you tighten the axle, so that the rotor is in the exact right position; but if it rubs, try lifting the bike off the ground and then tightening the axle, maybe your mechanic did it that way

Then the day comes, your mechanic turns to you with a grim look on his face and says ‘it’s time to replace your brake pads’. ‘Why the look?’ you ask, don’t you just pop the old ones out and new ones in? Oh no, even replacing pads is a potential adventure with discs. At a minimum the wheel comes out so the pistons can be pushed back, but if a piston has become sticky or the brake wasn’t setup properly to start out with or… well god knows what the problem might be… but if the caliper needs to be loosened then it’s off to the races. Time for the bill… whoa! $154 for new pads? Yep, because you needed a new rotor too and it took ½ hour to get them adjusted and bedded in – pads $29, rotor $65, labor $60… and that’s just one brake.

So yea, disc brakes are great, but like a lot of modern things they’re way more complicated and expensive and temperamental than their predecessor.