Repair to bent rim. Advice and help pls

Escammed

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Jan 14, 2018
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Hi, I need some help and advise with a situation I've found myself in!
I have a Magic Pie Vector which has been flawless, till I hit a pot hole and bent the rim.
Had an new rim fitted at a local bike shop and this is where the issues begin.
Aside from being slugged with a bill close to 300% more than the initial quote (with no contact to confirm if the the price hike was okay). I'm left with a wheel that feels really unsafe to ride. The motor feels "loose" in the rim if that makes sense?
A lot of the spokes are literally loose with no tension at all on them. And every 3rd/4th spoke has what looks like an intentional bend in it?
When I ride along there is a lot of creaking noise coming from the wheel. I went for a short ride up the steet, it really doesn't feel safe at all! I don't want something bad to happen when I'm hooting along at 40+ km/h.

What should I do now?
 
Take the wheel back and demand that they tighten the spokes to 1000 newtons. That's the least they can do after charging you full price.

My shop charges USD$50 plus the cost of spokes and rim. The wheel will always be true, round, centered over the hub, stress relieved, and tightened to at least 1000N on the tighter side.
 
EDIT: Chalo replied while I was typing, so what he said first.


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original post:

If all the spokes are loose, they need to be retensioned and trued or the wheel is going to disintegrate while you're riding, at some point.

If the shop didn't even bother tensioning and truing the wheel, you should get your money back and go somewhere else.

If the wheel *was* tensioned and trued when you got it back, but became loose after riding it, then probably the original spokes were re-used, and are too thick for the new rim, and they are deforming the nipple holes in the rim, allowing the spokes to loosen.

In that case, you'd either need to get thinner spokes of the right length, or a stronger rim. (probably would need a new rim anyway, since it's probably already damaged in that case)

If they did not reuse the original spokes, and instead used regular bicycle spokes, then it's unlikely the above is a problem, and it was probably just not correctly tensioned in the first place.


FWIW, you can tension and true a wheel yourself easily enough, especially if you are not using rim brakes (it doesn't have to be as true). There are a lot of threads about doing it here on ES (some are in the Sticky Index threads at the top of each forum), and also out on the internet in general, including videos, usually under "wheel building". Bike shops almost always carry spoke wrenches. If you don't know what gauge spokes you have, you can get a multi-gauge "ring" tool, but probably you have 12g spokes (it's a common OEM gauge) if they reused the original spokes. If they used new spokes, they probably used 14g or 15g.
 
Chalo said:
Take the wheel back and demand that they tighten the spokes to 1000 newtons. That's the least they can do after charging you full price.
AMEN
 
You might do that, but its pretty clear that they don't know shit, and spent too much shop time on it trying to figure out lacing a motor wheel. Not tempting to let them touch it again. For starters though, a new wheel will loosen almost immediately from the motor torque, if cheap spokes were used. So what happened might be normal. A well built wheel using decent spokes would take a few hundred miles to loosen up. Yours sounds like it was never very tight to begin with. Somebody in the shop said f this.

Time to learn to true a wheel yourself. It will be hard the first time, but not as hard as you might think. Starting point is loosen all the spokes some, getting them all the same. Do this by sound, a tight spoke pings, while a loose one goes thud.

Never tighten up any nipple more than a half a turn at a time. I like to start by getting the nipples all lined up same. so when you put the wrench on, its 90 degrees to the rim on all nipples. this just makes it easy to adjust each spoke the same, as you go round and round.

Write it down which way is tighten, you will forget and start loosening when you want a half turn tighter.

Once all loose, then tightened back up till they just ping the same low note, your wheel should be sort of straight. If its not, like really bad off, and really abrupt where its bent, they sold you a bent up rim. Don't sweat the bent spokes, right or wrong, they did that for a reason.

Now make a wheel truing gauge out of a zip tie, or some wire, that will show you the straightness of the wheel as it rotates. Attach the zip tie to the frame or fork, and cut to just the right length to just touch the rim, where you want it to be, centering the rim in the frame. One on each side helps, but you can do it with just one.

Now just start going around the wheel, slowly tightening each spoke as the gage tells you. Look at the lacing pattern. see the groups of 4 spokes? Think of how to adjust each group of 4 to make the rim straighten. Get the egg shape out first, then work on side to side. Never tighten any nipple more than a half a turn at a time. In general, in each section of 4 spokes, you will tighten two only for side to side, and all 4 to get out egg shape.

Go slow, and take breaks, even overnight so you don't get all frustrated. you don't have a tension measuring tool, so ping the spokes and do it by sound. In the end, if the wheel is not already bent, all will ping about the same note. Not a crazy high note, but a middle c or so. At some point, if you tighten enough on one side, you get too tight on the other two nipples, and have to loosen them back to a middle note.

You can get it done, maybe not perfect, especially if riding a loose wheel bent your rim. But you can do it. Now you know how to keep your wheel tuned, and avoid ruining wheels by riding a loose one.

Re the shop, there are things you can do to try to get your money back, if you have the time and the balls. Stand in the street with a sign near the shop awhile, for example. If they come out and assault you, cha ching.
 
You didn't say whether you'd put some miles on the wheel between picking it up from the bike shop and it becoming loose. If you had done so, then the wheel loosening might be more a matter of bad hub design (holes too big, flanges too close together) and inappropriate component choice than of the bike shop doing a poor job of assembly.

If that's the case (if the wheel unscrewed itself while you rode on it), then simply doing up the spokes more tightly might not help much. So in that case, ask the bike shop to put spoke prep on the threads before tightening and truing. It's a kind of mild glue and dry lubricant that helps prevent nipples unscrewing. If it happened to my shop, I'd do the follow up work for no extra charge.

Your original wheel might have had glued nipples, or they may have been sticky because they were low quality parts with rough threads.

Usually the best way to build hub motors in bicycle rims is with 14ga or 14-15ga spokes, cross-1 lacing, all the spoke heads facing inwards, and the rim holes reamed at an angle if that's what it takes to keep the nipps in line with the spokes. Often this means washers are necessary under the spoke heads, nipple heads, or both.
 
Thanks for the ideas guys. To answer some of the questions, they used the original spokes with new nipples. I rode about 400-500m on the new rim. Some of the spokes were quite loose before it was ridden on. I have have never tried to true up a wheel before. Using the above instructions I'm sure I could do it. I'm torn between taking the time to do it myself properly or taking it back and possibly having someone screw it up again.
 
Loose spokes right out of the shop would not have me going back there, but on the other hand I built my first wheel at age 13, so no big deal for me.

Never too late though. IMO if you ride hub wheels, you should at least learn to tighten up a loose wheel before it goes really bad, bends the rim, etc.

As Chalo said, if they keep on loosening up, your wheel sucks too much to ride much on it, unless you are willing to snug it up as much as daily. My own experience is different though, I have had some pretty janky wheels settle in, and stop loosening up after a few months of regular spoke adjusting. The loose spokes from day one made it worse, so maybe you can get this wheel to settle down. Personally, I don't require a wheel to never creak. I use the creaking to tell me when to check it. Gets louder, or more spokes are talking time to check the wheel. No sound might just mean all your spokes are over tight, which then wrecks spokes and nipples, or even pulls a nipple through the rim.

This is for a straight rim. once that thing is bent to hell, getting it straight means way too tight on two spokes, way too loose on the other pair in the set of 4. Always bad, and perfect for more problems. Junk a bent rim if your new one is bent now.

The last thing you want to do, is ever ride on loose spokes. Carry that spoke wrench so if you suddenly realize you have a really loose one, you can quickly snug it up and keep riding. Do the actual truing later. just snug up to prevent more damage on the way home.

Do try for a bit of your money back, since you never plan to spend a cent in that place again!!!
 
Cool.
A bit of an update.
I did decide to give them a second chance to do the job properly. I figured that may have one of their more experienced mechanics do the job or make sure it's done properly.
Picked it up yesterday and checked the tension of the spokes before I left the shop. They all felt okay.
Went to fit it today and thought before I spend the time to fit and wire it up I would check to make sure the wheel is true. Nope. Out of true by a good 5mm.
FFS!
 
Yikes, that's really bad. I have built some wheels on rims that bad. I unlaced them, sent them back and started over.

Can you share with us what kind of rim they used? The rim is not necessarily the problem, but... it probably is. It would take a truly exceptional amount of incompetence to get a result like that from a round flat new rim with a good joint.
 
The rim is a velocity chukker 700c.
It was @ 1-2mm out of true before they tightened the spokes.
Took it back again, will give it one last go.
 
By "Out of true by a good 5mm", do you mean that it is out of round (oval with the high spots 5mm larger diameter than the low spots), or that it's laterally (side-to-side) "wobbly", where when measuring on only one side of the rim (to the frame) there's spots where it's 5mm closer to the frame than other spots?

Or do you mean it's offset (dished) 5mm too far over to one side or the other, but is round and "straight" side to side?

Or something else?
 
I was just checking, because if it was just offset (dished) it's easy to live with (as long as you don't use rim brakes and the tire doesn't rub the frame), as long as it's fully tensioned correctly so it doesn't come undone as you ride.

But yeah, 5mm is REALLY crappy.

When I was first learning how to fix / rebuild wheels, I managed to make some that bad, but quickly (days, little reading and video watching on the internet) learned how to fix that and prevent it.

Hard to believe a shop earning money for their work could manage that level of incompetence, assuming they've ever actually worked on a wheel before, but I guess it happens. :roll:
 
Chukker is a good rim. At least it was when they bought it. This all comes across as very unfortunate.
 
It's pretty clear to me after questioning them today that they never even put the wheel on the truing stand during or after re-tensioning the spokes.
Will see tomorrow what their efforts yield.
 
My personal opinion is I wouldn't trust them not to just sabotage it (deliberately or more likely thru incompetence) so that it fails catastrophically during a ride. :/

If they're not even doing their work on the truing stand (I'd wonder if they even have one or know what it is), are they even checking how tight the spokes actually are? Or just tightening them until they can't crank them down any more because the rim is cracking at the nipple holes and warping? In that case the rim could be damaged in a dangerous way, unless you check the spokes every ride from now on, because a cracked rim will continue to worsen until the spokes get loose (and retightening them doesn't work because the rim can't support them anymore due to the cracks).

I'm no professional wheelbuilder, but I would certainly care a lot more about what I handed to someone than they do, because it's what's holding a person up while riding, and a failure can kill someone if it's the wrong failure at the wrong moment.
 
The shop screwed you and is incompetent so do a chargeback and find another one. Simple.

Oh and you can tighten your spokes yourself and probably get the wheel in good riding condition. Just do one "position" at a time and skip your way around the wheel so it tightens evenly. Bang on the spokes to figure out the tension if you don't have a torque wrench. It will take you about 15 minutes max. The goal is to get them pretty darn tight but not so much you feel like you're going to break or strip something.
 
By now I'd be riding around in front of that shop with a sign on my bike. No way I'd be letting them touch it again, but I'd want all but the price of the rim back.
 
Got the rim back Friday. Spokes are tensioned and the wheel is true. Riding on it today to see how it holds up. The cheeky f-er let me know there would be no charge for the work done. WTF! I bit my lip and walked out (I'm trying to be more calm these days)
By the time I got home the tyre was flat. Pulled the tube out and can see a tool mark where the puncture is. Couldn't believe it!
 
I sincerely hope its not the only bike shop in town.
 
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