I was working on my bike in my driveway when I walked into my garage for just a moment. I heard a sudden gust of wind, and turned my head to look outside just in time to see my Trek Domane, clamped in a work stand, toppling over.

Violently wrenched loose from the stand, my heart sank as I saw the strands of carbon fiber poking out from the bike’s scraped top tube.

Over the next few days, I considered how to repair the bike’s carbon fiber: should I replace the frame completely or get it repaired? A new frame would set me back around two grand, even with Trek’s replacement program. I reached out to Broken Carbon, LLC in Boulder, Colorado; their repair estimate was a more palatable $525, but basic paint beyond the essential clear coat would be an extra fee; shipping my bike to and from the facility would not be cheap, either.

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Friends on social media made another suggestion: fixing it myself. Although I do much of my own basic bike maintenance—cleaning and lubing my bikes regularly, replacing chains and cassettes, and so on—I was reluctant to take on a task with such a high, potentially catastrophic risk.

It got me thinking about whether an Average Joe cyclist should attempt certain bike repairs themselves, or leave it up to the professionals. I reached out to Charlie Revard, co-owner of the Bike Line in Indianapolis, Indiana, for his thoughts.

“Working on your bike during a pandemic could be risky,” Revard told Bicycling. “If you unwillingly break something by accident you may not be able to easily find a fast replacement [because of the current supply chain issues].”

For me, there are few feelings as good as knowing I was able to fix a problem and keep my bike rolling myself (and often, with the help of some very good friends). But for most bike repairs, specialized tools are needed, and Revard advises riders weigh the benefits of buying the tools versus just paying your LBS to do it for you. What’s the likelihood of you needing to make the same repair in the future? How much time will it take you to complete the repair versus a pro? For most people, the time and money saved makes handing it off to a mechanic more than worth it.

Here are several mishaps that riders encounter, and whether you should go about attempting to repair it on your own, haul your bike into a shop for repair help, or replace the part altogether.

The Problem: Stripped Crank

Repair It Yourself? Yes, and You Have Options

If you work on your bike often, one of the most common issues you can encounter is a stripped crankarm. Typically, this happens when you accidentally cross-thread the pedal.

How to Fix a Stripped Crank

You can repair light thread damage with a pedal tap. Park Tool, a bike repair company, offers pedal taps; you can also purchase a standard pedal tap at most hardware stores. To repair, simply ratchet the tap through the damaged threads.

If the damage is more severe—for example, if the threads are almost completely disintegrated—you can still salvage the cranks using something like Unior’s Crank Saver Kit. Basically, you’ll hollow out the old threads, then insert new sleeves in their place.

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If you don’t want to invest in the tools or the time, you can simply replace the damaged crankarm … assuming it’s the left side. (The right arm is attached to the crank, while the left is a standalone arm that bolts onto it.) You’ll need to replace it with the appropriate length and preferably the same model—though I doubt anyone will notice if you replace a Shimano Ultegra arm with a 105, though.

If it’s the right-side crankarm, you’re likely better off replacing the whole crank set. Both options are relatively easy and can be done with the help of YouTube tutorials, such as the one below:

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How to Remove and Install a Crank Arm on a Bike
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The Problem: A Bent Wheel Rim

Repair It Yourself? Yes, But Only If the Wheel Is Not Too Bent

If the damage is relatively slight, most riders can repair a bent wheel rim themselves with the correct-sized spoke wrench and a lot of patience. A truing stand will help, but you can also just flip your bike over. (Rim brakes can be really helpful here, allowing you to better visualize where the bend is via the distance to the brake pads.)

How to Fix a Bent Wheel Rim

To fix it, tighten the spokes on the opposite side of the bend by a half turn. Depending on how bad the ding is, you may have to slightly loosen the spokes nearest the bend as well. Repeat as needed. If needed, you can find more in-depth instructions here.

“A professional can make this repair quickly, and the repair will be more likely to last,” said Revard. But, if this is a common problem for you as a cyclist, it’s probably worth your time to learn how to make this repair.

If the rim is bent severely, your best bet is replacing it. You can probably salvage the hub and rebuild the wheel with a new rim and spokes, but it’s almost always cheaper and more cost effective to buy a brand-new wheel.

The Problem: A Bent Derailleur Hanger

Repair It Yourself? Fix It in the Field, But Replace It Immediately After

One of the most common results of crashing on your drivetrain side is bending the derailleur hanger. The hanger is specifically designed to absorb the impact, thereby saving your pricier derailleur or frame.

While you can often bend the hanger back enough to ride back to your home or car, it’s usually best to replace it before your next ride, lest your shifting suffer and eventually the hanger breaking catastrophically.

How to Replace a Bent Derailleur Hanger

Luckily replacing the hanger is fairly easy. Remove the wheel, unbolt the derailleur from the hanger, then the hanger from the frame. Install the new hanger after cleaning and greasing the area. A few manufacturers sell alignment tools that will help ensure the hanger and derailleur are correctly in line.

The Problem: A Non-Compressing Suspension Fork

Repair It Yourself? Yes

Mountain biking is dirty business, and that muck can cause havoc to components, especially your front suspension fork. Most manufacturers, such as RockShox, recommends servicing their forks around every 50 hours of ride time. It can be a pretty routine task that requires only basic tools, some replacement oil, and occasionally new seals and rings. (You can find a great instruction video here.)

Even with regular service, you may find that your fork won’t compress.

How to Fix a Non-Compressing Suspension Fork

After noting your air-pressure and suspension settings, release the air pressure from the fork. Remove the rebound adjuster knob, then loosen the bottom bolts. Tap the bolts using a hex wrench and mallet to dislodge the shaft from the lower leg from each side, then remove the bolts. At this point, oil should be draining from the fork. (Make sure you have an oil pan underneath the fork to catch the draining fluid.)

Using a metal pick, remove the foam rings; if they’re still in good condition, clean them with alcohol, then soak them in suspension oil. Thoroughly clean the fork legs and seals, then replace the rings. Grease the seals, then replace the shaft onto the legs. Using a syringe, replace the oil. (The type of oil and the amount needed for each leg should be on the fork manufacturer’s website.) Replace the bottom bolts and adjuster knob. Replace the air with a shock pump and your fork should be as good as new.

The Problem: Damaged Carbon Fiber

Repair It Yourself? No, Get Expert Help

repair or replace
The damaged carbon fiber on the author’s bike.
Courtesy Robert Annis

I wasn’t willing to attempt the carbon-fiber repair to my bike myself, but luckily, a friend, Brett Conway, offered to help me out. I sanded the damaged area, then continued around the top tube, eliminating the paint, getting down to the carbon fiber.

From there, Conway took over, cutting strips of carbon fiber, coating them with epoxy, and wrapping them around the bare area. After applying two strips, he wrapped it up with heat shrink, then used a heat gun to finish the job. (I removed the heat shrink 24 hours later.)

In all, the repair took less than 90 minutes. I can either leave the repair as is, or sand the raised carbon fiber smooth and even, then repaint it. Conway has repaired many bikes using this method, and I wouldn’t have attempted it without his capable assistance. Had the damage been worse, say a large crack or along a structural support, I would have paid for a professional repair.

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Robert Annis

After spending nearly a decade as a reporter for The Indianapolis Star, Robert Annis finally broke free of the shackles of gainful employment and now freelances full time, specializing in cycling and outdoor-travel journalism. Over the years, Robert's byline has appeared in numerous publications and websites, including OutsideNational Geographic Traveler, Afar, BicyclingMen's Journal, Popular Mechanics, Lonely Planet, the Chicago Tribune, and Adventure.com.