Anyone got experience at straightening a spoked wheel?

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My front wheel has had a wobble ever since I've had the bike. The wheel is now in a jig on my bench so that I can tune it out.

Anyone got any experience at doing this as its not turning out to be particularly easy? I've read up on the theory, so I know the basic approach, but it seems like one of those jobs where theres no substitute for actually having done a few before.

I started by just adjusting a few spokes either side of the wobble, but it seems that the whole wheel was under so much tension that nothing really moved, so now I've loosened off all the spokes to try and pull it straight then tighten everything up evenly.

Getting the rim concentric to the hub isn't a problem, but tuning out the wobble is.

For speed I've not taken the tyre or discs off yet, I was hoping to get away without that. Will it be a lot easier with no tyre fitted?

Anyone got a few pearls of wisdom?

Thanks, Mark.
 
i would take the tyre off as the bead may well be holding the rim out of true i've built cycle wheels before and they are always bare then re-tensioned after 200-300 miles after the spokes have bedded in
 
If it is on your GS, aren`t the externally spoked wheels particularly awkward to do? I am sure I read that somewhere.:nenau
 
short answer:

according to pros i've spoken to, what you are attempting can't be done. wheel needs to be in a jig, and all spokes equally tensioned.
 
I have a lot of experience mainly with cycle wheel building, including training mechanics, but have done a few motorcycle wheels and the principles are the same.
The big problem with truing a rim the size of the GS is that if it's damaged no amount of tensioning the spokes will true it. I should not think the tyre would make a huge difference but it would be easier to get it out of the way.

So the first thing to check is whether the rim is damaged, whether it's kinked sideways or has a flat. If it's bad you'll need to replace it, but if it's just a kink then just re-tension.
When you re-tension, the important thing is to have even and high enough spoke tension. High enough tensioned spokes will stop the spokes snapping by preventing one spoke being continually tensioned and released every revolution. They need to be evenly tensioned to keep the wheel true and round, or as true as the rim was when you started!
You should be able to use a torque wrench on the nipples to measure the tension.
The best tip I can give is to start all the nipples at the same point on the thread and do them all up a small amount at a time. Start next to the valve for reference and put one turn each spoke all the way round. Then another half or full turn all the way around until you get the right tension. Then worry about the truth and roundness of the rim.
If you start from the same place and tighten all the spokes the same, it will true itself.
 
Jimbike said:
I have a lot of experience mainly with cycle wheel building, including training mechanics, but have done a few motorcycle wheels and the principles are the same.
Click to expand...

not with these rims, not from what i have been told by wheel builders.

they need to be built, dead true, in a jig, then tension the spokes. truing after build is not possible. if the completed wheel is out of true, you start again.

not done it myself, not even a bike wheel, but i have spoken to people who have, and most of them won't touch another.

devon rim co. are the only firm i know of that will rebuild one of these wheels.
 
It was an accident. Claim on your insurance and get a nice new rim.
 
cookie said:
Jimbike said:
I have a lot of experience mainly with cycle wheel building, including training mechanics, but have done a few motorcycle wheels and the principles are the same.
/QUOTE]

not with these rims, not from what i have been told by wheel builders.

they need to be built, dead true, in a jig, then tension the spokes. truing after build is not possible. if the completed wheel is out of true, you start again.

not done it myself, not even a bike wheel, but i have spoken to people who have, and most of them won't touch another.

devon rim co. are the only firm i know of that will rebuild one of these wheels.
Click to expand...

They are like lots of cycle wheels in that the spokes are in the hub and they cross from one side to the other which confuses a lot of people, especially experienced wheel builders as it feels totally backwards.
Lots of old school bike shops (and motorcycle shops) think wheel building is a black art and many have forgotten to think about what they are doing. There are lots of mechanics who won't touch them either but they are fine if you think about how it's built.

You're right, you cannot do much truing when any wheel is at full tension, but you shouldn't need to by that stage.

Like I said, start with a true rim, start from all the nipples in the same place and gradually increase tension evenly and it'll true itself.
Click to expand...
 
Thanks for the responses.

The AdvRider link is a good one. Very impressive bike. What he describes is exactly what I was doing.

I'm sure it is possible. Its just a case of doing it slowly and methodically.

Looking at the Devon Rim Company website, they only charge £40 for building a wheel so if it all goes wrong then it's not a mega money job to have it put right if I need to.

I'll get the tyre off tomorrow night and have another go.
 
Jimbike said:
[Like I said, start with a true rim, start from all the nipples in the same place and gradually increase tension evenly and it'll true itself.
Click to expand...

Ok with your logic.
But have you actually done any of it on a BMW spoked GS wheel.
Not read or knows someone who has.. have YOU done it ?. Simple yes or no. :D
 
Hi Steptoe

No :D I haven't done a GS wheel and didn't mean to sound like a smartass but was trying to be helpful. I have built, trued and trained shop mechanics how to build every sort of cycle wheel including plenty with a very similar spoke pattern to the GS ones. They are different so confuse most shop mechs used to a standard wheel, but a novice looking at it from first principles could do it.
He was having a good go and obviously understood the basics so was worth having a go and learn rather than spending money and time and not being any the wiser.
 
Ok, progress report.

Tyre & discs off. All spokes set very loose, spin the wheel and it isn't too far off.

Gently snug up the nipples without putting any strain in one place on the wheel and its about 4mm off radially and 8mm off axially.

Loosen one side, tighten the other, no more that 1/4 turn at at time and the radial play is now 1mm.

Start on the axial play, again no more than 1/4 turn at a time and its down to 5mm.

I stopped at that point as I was getting tired and didn't want to bugger it up, but the plan for tonight is to continue at the axial play, then revisit the radial, and finally the axial again. Then tighten all uniformly. If I can get down to 1mm on both axial and radial I'll be happy.

So far I've learnt - its easier with no tyre fitted, start with all spokes loose, never turn any nipple more than 1/4 turn at at time, only adjust 3 or 4 spokes each side of the wheel before rechecking for trueness.

Mark
 
Good result.

Just been out for a ride and I can't feel any wobble at all. I ended up with under 1mm axial and about 1.5mm radial.

I was cruising at 80 today with a few quick bursts up to 90 plus and the bike is rock steady.

Very pleased to have sorted it out myself - Woody may well be the man, but Australia's a hell of a long way to go :)

Mark
 
Well done you:clap they are not the easiest wheel to work on. FYI Woody is just over the pond in the States not here. Very pleased to have sorted it out myself - Woody may well be the man, but Australia's a hell of a long way to go :)

Mark[/QUOTE]
 
Nippy Normans supply Touratech, Wunderlich, Desert Fox and many other makes of accessories.
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