how to tell a wheel buckled?

[NorthernSky]

Hi

i've just bought a new bike and i'm a tad concerned (or paranoid) the back wheel is slightly buckled

is there a simple way to tell?

it seems to scrape off the brake pad in a rotation.

 

[Rhythm Thief]

Sounds like it has a bit of a buckle. You might be able to fix it with the correctly sized spoke key and some gentle tweaking of the spokes.
Slacken the brake blocks off and hold a felt pen against the seat stay with the tip just touching the rim at the point where it's buckled. Then spin the wheel. This should mark the extent of the buckle.
Tighten (very gradually) the ones going to the opposite side of the hub from the direction of the buckle, until the wheel is pulled straight again. DON'T over tighten the spokes! You might also have to loosen the spokes on the "buckle side" of the hub. Only adjust the spokes which are in the marked area of your rim.
It's easier to do than to explain.

 

[Rob3rt]

Does it scrape all the way round or just like at one point? If the former, check that its seated straight in the dropouts, I got a puncture and when I put the wheel back on in haste, it was not fully seated and thus was slightly angled, not obvious to look at but was scraping the break at one side, do a quick slacken and re-seat to check its seated right.

 

[Globalti]

If it's a brand new bike take it straight back to the retailer and ask them to straighten the wheel, don't try to do it yourself or you'll invalidate the warranty.

If you have already ridden it, then it's almost inevitable that the wheels may go a little out of true as they settle down. You may have heard some pinging noises as the spoke nipples settled in their holes. I've never had a new wheel that didn't go slightly out of true. Tweaking spokes is a skill you need to learn so maybe you could find an old wheel and practice on that first?

 

[palinurus]

Could be the brake pads are just misaligned or the wheel isn't sitting in the dropouts quite right.

 

[Rhythm Thief]

Hmmm, yes. I should have added ... "first make sure the wheel is buckled". Perhaps by stamping on it, or something.

 

[PpPete]

If it's a brand new bike take it straight back to the retailer and ask them to straighten the wheel, don't try to do it yourself or you'll invalidate the warranty.

If you have already ridden it, then it's almost inevitable that the wheels may go a little out of true as they settle down. You may have heard some pinging noises as the spoke nipples settled in their holes. I've never had a new wheel that didn't go slightly out of true. Tweaking spokes is a skill you need to learn so maybe you could find an old wheel and practice on that first?

A good hand-built wheel will have been stress-relieved to get the "pinging" noises out of the way before the final true-ing. And it should not go even "slightly out of true" if the spoke tensions are even in the first place. Well not unless Rhythm Thief gets his hands on it that is....

 

[02GF74]

my understanding is that a buckled wheel is different to an out of true wheel.

buckled - the rim has suffered damage so is out of true. if you were to take the rim off the wheel by undoing all the spokes, then place the rim on a flat surface - there will be a point (or points) where the rim will not contact the surface due to being buckled.

now an out of true wheel has a perfectly straight rim - it will lie flat on the surface - but the adjustment of the spokes are pulling the rim unsymmetrically so the rim does not run centralised.

this can be fixed by adjusting the spokes to pull the rim into line - a buckled wheel needs to have the rim bent back into shape - not so easy or possible depending on the amount of damage and rim material - steel can be unbuckeld but aluminium alloy will have stretched so unlikely to be unbuckled successfully.

 

[Davidc]

If its new the dealer should be taking it back in after the first 250 miles as part of the sale. Many parts, including wheels, wear in after new and need to be readjusted.

Speak to them.

 

[NorthernSky]

I've actually only had it out once for a 5min ride to test it. apart from that I've been using it on my turbo trainer.

i used a felt pen and held it against the frame then let the nib run on the wheel. it goes out of contact at maybe one point by about 1mm or so

by your descriptions it sounds like its out of true not a buckle.

not sure if its worth the hassle of sending back, they may do more harm than good to it. then again if i leave it too long they wont take it back for repair or replacement
i bought it mail order so i cant walk into the store as such, it'll all be done by post.

can you all say if you done the same test your back wheel is perfect?

thanks for the replies as always

 

[palinurus]

Either learn to true a wheel yourself (plenty of advice on the web, video tutorials on YouTube etc.) or take it to your local bike shop, likely cost about £10. Not unusual for a factory-built wheel to go out a bit after a while.

 

[Rob3rt]

Why not go to a LBS and ask them their opinion and they may be able to re-true the wheel for you and/or show you how to do it yourself in the future?

I have no idea how to true a wheel myself so cant give any tips.

 

[ASC1951]

i bought it mail order so i cant walk into the store as such, it'll all be done by post.

That is the downside of not buying locally, so I hope you got plenty off.

can you all say if you done the same test your back wheel is perfect?

My wheels - handbuilt by my LBS - run true within about 1mm and generally wear out before they go out of true.

If it's only for your turbo, Cruiser, it doesn't matter whether it is out of true - just slacken the brakes off. If you want to true it up for the road, get yourself a spoke key and have a look at this. http://sheldonbrown.com/wheelbuild.html
It isn't that difficult to get it close enough, although I find that even with a jig I can't get 100% straight + true + round. I can get straight + true, though.

 

[NorthernSky]

thanks

i did get a good offer on it, thats why i went with online

i'll maybe just get the key as it seems to need very slight adjustment.

its actually my main bike, so once the weather picks up it'll be off the trainer and onto the street so i want it in tip top condition

ta

 

[02GF74]

i used a felt pen and held it against the frame then let the nib run on the wheel. it goes out of contact at maybe one point by about 1mm or so

by your descriptions it sounds like its out of true not a buckle.

1 mm is nothing but I would if it were my bike, take that out.

yes, out of true is what it sounds like.

google for how to true a wheel or do it yourself.

quickie:
mark the rim for all the spokes that are out, say touching the pen, so
you need to pull the rim away from the pen

undo by 1/4 turn all spokes on same side in between the marks and do up by 1/4 turn the spokes on the other side - will pull rim other.

repeat the marking and continue.

note that this should be done on regular spokes wheel i.e. with 32 spokes - on special wheel say 10 or so spokes, they are done up to much higher tension and it is easy to mess up.