11 Trailside Mountain Bike Repair Hacks


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Mountain bikers of all experience levels can likely name a time they encountered a mechanical problem off the grid. We asked some of our trail-savvy REI colleagues for repair hacks that can help get you back to your car.

1. Patch a Punctured Side Wall

Mountain Bike Repairs

Let’s start with a common fix. If you slice a hole in the sidewall of your tire, place a folded dollar bill, an empty energy gel packet or a gum wrapper on the inner wall of the tire and pump it up to full pressure. The barrier can help prevent the tube from pushing out of the hole, hopefully long enough to get back to your car.

Flat Tire Prevention for Your Bike

2. Ride Out with a Broken Rear Shift Cable

Mountain Bike Repairs

If your rear shift cable breaks, the sudden lack of tension will cause the derailleur to move to the hardest gear, where you’ll be stuck. Assuming you don’t have a spare cable on hand, there’s a quick, temporary fix. Just tighten the high limit screw (usually marked with an “H”) to force the derailleur into an easier gear. Then hold your rear wheel off the ground and cycle the cranks a few times to allow the chain to move up the cassette. Now you can ride back to the trailhead with ease.

3. Zip Tie for an Out-of-True Wheel

Mountain Bike Repairs

When an out-of-true wheel is wobbly and difficult to ride on, attach a zip tie to the chainstay of the bike. Then, as you spin the wheel, the end of the zip tie (you may have to trim it to the right length) will graze the section that’s out of true. This will show you where you need to tighten the opposite spoke and pull your wheel straight. This is preferable to asking a friend to hold their finger against the edge of your wheel. Zip ties, in this case, are better than friends.

4. Shorten Housing for Extra Cable

Mountain Bike Repairs

This one requires a multi-tool or another cutting device (it’s also a little complicated, so stay with us here). If you break your shifting cable, usually where it’s exposed at the derailleur, you likely won’t have enough cable to reattach it.

  • First, move your shifter in on the handlebar to give yourself some extra slack in the cable and housing. Then, detach the housing at the derailleur, set aside the ferrule, and pull the housing down about 3 inches beyond the end of the cable (as you do this, you’ll see an equal amount of cable exposed at the shifter end).
  • Trim the extra housing and slide the remaining housing back up to expose the new length of cable at the derailleur end.
  • Replace the ferrule, reattach everything and be on your merry way.

5. Flipped Headset Cap for Loose Headset

Mountain Bike Repairs

If you have a loose headset and your headset cap has bottomed out in the steerer tube, remove the cap, flip it upside down and put it back into the steerer tube. You’ll get a few extra millimeters of adjustment with the contoured shape, which could be just what you need to tighten things up again.

6. Quick-Release Skewer as a Tire Lever

Mountain Bike Repairs

This is an easy hack for removing a flat tire if you don’t have tire tools with you. Just remove your quick-release skewer from your wheel and edge the lever between the rim and the tire to pry the tire off.

How to Remove a Rear Wheel with a Quick Release Axle

7. Fill a Flat with Debris

If you have a flat tire and you don’t have any patches or tubes, consider stuffing the tire with leaves, pine needles and other woodsy debris to fill it full enough to get back to the car. Mother Nature’s always got your back.

Bike Tire Basics: How to Fix a Flat

8. If You Lose a Crank Bolt

Mountain Bike Repairs

If you lose your crank bolt and need to attach your crank arm, try this trick. Attach two long zip ties (or several) to create one long length—long enough to thread it through the crank arm and spindle and double back again. At either end, place two small (but sturdy) sticks and attach the zip tie around them so they—and your crank arm—are held snugly in place. Take it easy until you get back to the car; no more shredding the trail with this fix.

How to Replace a 2-Piece Crankset

9. More Derailleur Issues

Mountain Bike Repairs

You’ll need to have a chain tool and quick link or master link with you for this hack. If you rip your derailleur off and you can’t shift gears, shorten the chain (about 5-6 inches) and  make it single-speed. Try to find the gear that will give you the straightest chain line. Note: This hack doesn’t work on a full-suspension bike.

How to Replace a Derailleur Hanger

10. Ease the Pain

Mountain Bike Repairs

Your bike may be broken but that won’t break your spirit. Celebrate your resourcefulness with a beverage! Turn your bike upside down, crank the pedal and hold your bottle cap to the knobby tire as it spins. Pop the cap and your day just got much better.

11. Walk It Out

Mountain Bike Repairs

If all else fails, channel your inner Hulk and carry your bike back to the car. At least you’ll get a great upper body workout.

Have any more mountain bike hacks? Please share them in the comments below.