"MacGyverisms"

"The pushme-pullyou rim fix."


You swear you didn't see that pothole-rock-tree branch in the road/trail. however, your wheel did...

So now you have a nice bend in your rim. You can't ride it like this because it causes your brake pad to grab, or even rub against the tire at that spot.

So what do you do?


This MacGyverism is used when your wheel gets a straight on blow, resulting in a inwards bend in one place (commonly known as a "flat spot").

Well, do you have an old fashioned leather toe strap on you, or your bike? If not, then be a good MacGyver and find something real strong that you can tie tight, it just may get you home after that mishap which kinked your wheel.

Start by taking the wheel off the bike, then remove the tire from the wheel.

Now find the bent spot, and a wooden fence or sign post. Or at least something softer than your rim, yet strong enough to take a little torque. Make sure it is not too big around, as you are going to be tying your wheel to it!

Loosten the spokes in the bent area, then tie your wheel to the post or fence. Be sure the toe strap, or whatever you're tieing your wheel with is passed through the two spokes at the center of the bent area!

Got it secure? Good. Now you're ready to pull the bend out of your rim.


Grab a hold of your wheel and roll it back and forth, as hard as you can. As you do this, the toe strap will try to prevent the wheel from rolling. And it will do this by pulling against the rim, right at the center of the bend.

If you're pulling hard enough, it will pull back hard enough to bend the flat spot back round, or nearly so. It's actually better to bend it just a tiny hair past round, then true it back into shape.

Check your work by holding the wheel by the axle ends and spinning it while watching the edge. If the first series of hard rolls didn't do the trick, repeat the process until it does. Remember, always position the strap so that it's in the center of the bend. This is sometimes marked by a small "blip" in the rim wall, which was caused by the impact.

(This blip can usually be straightened out somewhat by bending the rim wall back into shape with a cloth wrapped adjustable wrench.)

When it's straight, that is, round enough, retighten the spokes you loostened and true it using a spoke key. You can use an adjustable wrench, but be sure the jaws are fitting tightly around the spoke nipple or you might round the corners.


It won't be perfect, of course. it never will be again. But it should be close enough so that you can true it enough to ride the bike. And of course, the rim is no good for anything other than getting you home. But then again, it was ruined anyway. Replace it at the first opportunity. The spoke tension has been shot all to hell and the wheel's strength will be compromised.

Also, be carefull getting home, especially if there was a blip in the sides of the rim, because your brakes may still grab slightly at the spot that was bent! Remember, your wheels are no longer perfectly round.

"Wow! you saved the day again!"-->

Have a question?
or a MacGyverism of your own?
Write me and tell me about it!

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