Straightening a wobbly wheel

[KneesUp]

My bike-build project is almost complete. I just have a back brake and the wobbly wheels to sort out now.

I've never straightened a wheel before, but I can hire a work stand and the tools for not much at a local scheme.

I get the basic idea of finding the biggest wobble and adjusting the spokes there and carrying on - but is it easy? I've got two wheels to do, and the LBS charges two and a half hours worth of tool hire per wheel. Would you do it yourself or get the LBS to do it?

Also, the back wheel needs quite a few new spokes. How do I know what size I need?

 

[Tim Hall]

I find truing wheels fairly tricky, leastways getting the final little bit right is tricky. Coarse adjustments are easier. I think patience is a key requirement.

Regarding the new spokes, the best way will be to take an existing one off and take it to the LBS saying "I'd like x more like this please".

 

[Skyfoil]

If you've never done it before, it would be better to get your LBS to sort it, otherwise your tool hire will end up greater than they'll charge you anyway.
Last time I straightened a wheel and added a couple of spokes it took me about two hours.
First time I tried to straighten a wheel, it didn't go so well.
Patience is a must.

 

[KneesUp]

Patience and time are both at a bit of a premium here

LBS it is then, because the back one that needs the spokes is really rather wobbly.

 

[PpPete]

is it easy? quite easy if you understand what you are doing - if you are not sure there is a good sticky here or get the wheelpro book.
but personally I find building from scratch easier than truing old wheels

Would you do it yourself or get the LBS to do it? always DIY
Also, the back wheel needs quite a few new spokes. How do I know what size I need?
Wot Tim said, but don't forget right and left will be different length on the back wheel.

 

[sittingbull]

I use the brake caliper to true the rim.

Start with it open just enough to clear the worst section of wobble, true the wheel a little, tighten the brake cable to close the caliper a little, spin the wheel and listen for the drag and true again. Repeat as necessary until caliper clearance is mm perfect. It's best to remove the tyre whilst truing.

Every now and then look down the centre line of the bike to make sure the wheel is not going off-centre due to the caliper being off centre. Adjust if necessary.

I've found this method successful numerous times for truing the wheel laterally, but truing radially is much harder and it's only when you spin the wheel at speed that any degree of "hammer" becomes apparent. However I've always found this negligible and non-discernable in relation to our poor road surfaces anyway.

 

[John the Canuck]

I use the brake caliper to true the rim.
Start with it open just enough to clear the worst section of wobble, true the wheel a little, ................

i've trued [NOT BUILT] 4 now -- all ok - beginners luck.?
i only tighten/loosen each spoke 1/4 turn then check again - easy does it is the way

i get the brake shoe to 'just' rub - the wheel then stops at the high point

now...i have a choice [lets assume the high spot is on the left of the rim]
tighten the opposing RHS spoke to pull the rim away
loosen the adjacent LHS spoke to allow the existing tension in the RHS spokes to pull the rim across

i decide based on the tension 'ping' in the spokes under question
LOW PING is the one to tighten

SUPER PRIMITIVE - AND NO DOUBT NOT THE BEST WAY
BUT SO FAR IT WORKS AND NO PROBLEMS

YMMV

 

[I like Skol]

You can easily true a wheel in the frame without the need for a fancy stand, the only tool needed is a spoke key. In fact this is how I build all my wheels. As has been suggested already, to check trueness (radially and laterally) all you need is something across the forks or stays. I use some tape and you can either mark it with a pen or put another piece of folded tape stuck out to show where the rim wall should be. Once you get down to the final fine adjustments you can simply spin the wheel and listen to when it brushes or skims the tape. To make sure the wheel is dished correctly don't do it by eye looking along the bike as has been mentioned above, this is a very inaccurate way to go about things and will not give a good result. The effective way to do it is to flip the wheel around the other way and check the rim is still in the same place. Even on a heavily dished rear wheel the rim is still at the central point in line with the middle of the axle.

 

[John the Monkey]

One further tip, wear eye protection - old spokes can be quite intolerant of increased tension, and fly out of the rim with some force if they snap.

If you're taking a spoke out to take to the LBS, be careful - slackening one can increase the tension on the others, and I have a nice scar near my temple from trying to dismantle a wheel one spoke at a time - I always loosen them all a turn at a time now.

Truing stand & dishing gauge wise, the plans in the Wheelpro book are easy to build (I used scrap timber from kitchen cabinets and maybe £2 worth of screws and bolts from B&Q).

 

[sittingbull]

........ The effective way to do it is to flip the wheel around the other way and check the rim is still in the same place. Even on a heavily dished rear wheel the rim is still at the central point in line with the middle of the axle.

How is this any different to looking down the centre line of the bike and checking the rim is equi-distant between the chain stays? All you're doing is the same thing twice by flipping the wheel, instead of being 5mm off centre on one side it will now be 5mm off on the other. Am I missing something?

It's also useful to rotate the wheel and grab a handfull of spokes and squeeze hard to stress relieve the rim, repeat around the wheel and re-check trueness. Alternatively go for a ride, listen for the pings, then re-true.

 

[I like Skol]

How is this any different to looking down the centre line of the bike and checking the rim is equi-distant between the chain stays? All you're doing is the same thing twice by flipping the wheel, instead of being 5mm off centre on one side it will now be 5mm off on the other. Am I missing something?

Because you are using a visual check that can be skewed by parallax errors and then there are frame discrepencies such as bent frames (within manufacturers tolerances ), bent frames due to damage and also some frames have uneven chainstays to allow for chainset clearance. If you use my method of checking then there is no doubt that the wheel is right.

 

[KneesUp]

Thanks for all your advice. It sounds like something I'd like to do - but maybe this time I'll let the LBS do them and then I'll keep on top of them.

 

[John the Canuck]

Thanks for all your advice. It sounds like something I'd like to do - but maybe this time I'll let the LBS do them and then I'll keep on top of them.

naaah..have a go

 

[KneesUp]

naaah..have a go

They're already in the boot - I find it hard to get to the LBS when it's open to get spokes, and I'm busy all weekend - and I just want to ride the bike - I've been building it for months. It's only £9 per wheel plus a bit more for the spokes.