Centering a wheel?

It sounds to me like it's time to get a new rim. Have you checked the
tension on the spokes? If the spokes where you're low are of equal or
greater tension than the other spokes your rim is bent. If you can
afford it, get a new one. If not then live with what you have. You
will wind up over tensioning spokes and will possibly start breaking
them. You could even wind up with a complete failure and have the
wheel collapse. I've seen that happen before.

On Fri, 18 Mar 2005 22:17:23 -0600, "B.B."

may have said:

Question is: could I keep going the way I was going and pop that part
of the rim out, or will I need to loosen it up again and do a little
hammering?

Bear in mind that you can't actually hammer it back to the shape it
had before the crash; all you can do is bend it some more to put it
closer to where it started out, and there's a good chance that it will
end up in a not particularly useful condition. On the other hand,
it's not all that useful now, either, so there's not a lot to be lost
in trying; go for it if that's what floats your boat. Merely playing
with the tension is unlikely to return the rim to the correct shape,
and certainly won't both get it back to being round and permit proper
spoke tensioning in the bent area.

Quoted message said:

Or, third option, can I just live with it? Unless I'm creeping along
and looking for it I really don't notice the hop anymore and spoke
tension seems to be even. So can I expect this to be reasonably stable
or will it make itself worse in short order?

Many old steel rims used to do that brand new; yes, if you can live
with the hop, of course you *can* ride it, as long as the bend is not
so large that the tire bead creeps up and allows the tube to blow out.
It will also mean that your brakes will have a tendency to pulsate,
possibly badly; this may be more of a reason to ditch the rim than
anything else.

Given the number of problems with the wheel that you've described, I'd
replace it if it was on one of my bikes.

--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.

B.B. said:

After my recent accident I decided to give my bike a good once-over.
The only issue was that the rear wheel had a little hop in it. The
wheel's always had screwed up tension on all the spokes, so I decided to
do it right (sorta) and fully detension and retighten the wheel.
Anyway, I had about 1/5 of the wheel's circumference that was too
close to the hub, while the other 4/5 was pretty consistent. No
accurate measuring because my truing stand is my brake and the rim's
full of little dents anyway. (hence the "sorta" comment above) But that
1/5 was definitely too low.
My method of fixing it was to mark off that section and slowly
tighten the remainder of the wheel while backing off the marked area.
Seemed to work up to a point, got about half way to where it ought to
be. But then I quit making progress.
Question is: could I keep going the way I was going and pop that part
of the rim out, or will I need to loosen it up again and do a little
hammering?
Or, third option, can I just live with it? Unless I'm creeping along
and looking for it I really don't notice the hop anymore and spoke
tension seems to be even. So can I expect this to be reasonably stable
or will it make itself worse in short order?

There is nearly always a bit of hop at the rim joint (whether pinned or
welded). Is the 1/5 there?

Ummmm, perhaps I'm stating the obvious here..

Hire a professional?

(Oooh, ahhgggg...he said it! spend 20$ to have something done right!
Flame him flame him! banned from the newsgroup for life!)

bikeguy11968 said:

Ummmm, perhaps I'm stating the obvious here..

Hire a professional?

(Oooh, ahhgggg...he said it! spend 20$ to have something done right!
Flame him flame him! banned from the newsgroup for life!)

While there are certainly bicycle shops/employees that will do a good
job of rebuilding wheels (several among the rec.bicycles.tech regulars);
many not do it as well as an amateur with proper motivation and instruction.

--
Tom Sherman - Earth (Downstate Illinois, North of Forgottonia)

In article <[email hidden]>,

bikeguy11968 said:

Ummmm, perhaps I'm stating the obvious here..

Hire a professional?

(Oooh, ahhgggg...he said it! spend 20$ to have something done right!
Flame him flame him! banned from the newsgroup for life!)

Yeah, that was pretty obvious. I considered it and had a good reason
to not take it to a shop. Kind of implies I won't do it right, too,
which is just rude. And it doesn't really answer my question so much as
it tries to answer a whole other question along the lines of "Should I
take it to a shop?"
If that reply was meant to be helpful it really wasn't.

--
B.B. --I am not a goat! thegoat4 at airmail dot net
http://web2.airmail.net/thegoat4/

B.B. said:

After my recent accident I decided to give my bike a good once-over.
The only issue was that the rear wheel had a little hop in it. The
wheel's always had screwed up tension on all the spokes, so I decided to
do it right (sorta) and fully detension and retighten the wheel.
Anyway, I had about 1/5 of the wheel's circumference that was too
close to the hub, while the other 4/5 was pretty consistent. No
accurate measuring because my truing stand is my brake and the rim's
full of little dents anyway. (hence the "sorta" comment above) But that
1/5 was definitely too low.
My method of fixing it was to mark off that section and slowly
tighten the remainder of the wheel while backing off the marked area.
Seemed to work up to a point, got about half way to where it ought to
be. But then I quit making progress.
Question is: could I keep going the way I was going and pop that part
of the rim out, or will I need to loosen it up again and do a little
hammering?
Or, third option, can I just live with it? Unless I'm creeping along
and looking for it I really don't notice the hop anymore and spoke
tension seems to be even. So can I expect this to be reasonably stable
or will it make itself worse in short order?

--
B.B. --I am not a goat! thegoat4 at airmail dot net
http://web2.airmail.net/thegoat4/

Balanced spoke tension, on a per side basis, is very important. You can use the tone as your indicator.

You were going in the correct direction.

Quantify the amount of hop in 0.1ths of a mm if you can.
If it is less than 0.5 mm, I would tend to let it go.

Replacing the rim with one of the same Effective Rim Diameter (ERD) is an option you should consider.

If you are going to attempt to remove any distortions in the rim, you might want to get a copy of "the Bicycle Wheel" by Jobst Brandt ISBN 0-9607236-4-1. Many library systems can get it for you or you can buy it at some bicycle shops/or on line.
A few diagrams in the book will help more than words I can convey.
You will need to remove (or at lest detension spokes) in the bent area(s). Using a rubber mallet and blocks of wood as shown in the book is the way to try. Be careful not to overshoot. Position the supporting blocks on the outside of the rim under the area you are working and use a wood block on the inside of the rim where you strike it in the desired direction.
I agree with the telling statement in the book:
"Although some dents can be repaired satisfactorily this procedure is generally used only to make a wheel usable until a new rim can be obtained."
David Ornee, Western Springs, IL

if a new rim shows up then ura not gonna learn how to true the old one
unless you cut an old frame, muffler clamp it to a piece of 1/2 or
thicker ply maybe 4'x18" get a cheap spring clamp, clamp a credit card
to the frame and practice.
the hop will ruin your tire, bearings and dent the cones.
the adjustments our looking for occur at the lowest possible torque
levels-just beyond seating nipples on the rim surface.
is it a lateral hop or a radial hop?
the LBS hozan will take out some dents-go ask how to cheaply
strip the wheel and give them the rim?
getting it right takes some time
try an aluminum sun rim 18.
alum is harder to true but harder to dent.

In article <[email hidden]>,
daveornee <[email hidden]> wrote:

[...]

Quoted message said:

Balanced spoke tension, on a per side basis, is very important. You
can use the tone as your indicator.

Yup, I gave it the spoke test after I finished futzing with it and it
came out all even. Tension's even, wheel doesn't wobble side-to-side
much,

Quoted message said:

You were going in the correct direction.

Quantify the amount of hop in 0.1ths of a mm if you can.
If it is less than 0.5 mm, I would tend to let it go.

I think it's around a 1/16th of an inch, or about 1.5mm difference
between highest and lowest. It seems to me that the tire itself is
capable of taking up the difference when moving.

Quoted message said:

Replacing the rim with one of the same Effective Rim Diameter (ERD) is
an option you should consider.

These are old 27" steel wheels. Once it's financially possible I
plan to just replace the wheels & hubs as a set. Until then I'll have
to keep 'em working.

Quoted message said:

If you are going to attempt to remove any distortions in the rim, you
might want to get a copy of "the Bicycle Wheel" by Jobst Brandt ISBN
0-9607236-4-1. Many library systems can get it for you or you can buy
it at some bicycle shops/or on line.
A few diagrams in the book will help more than words I can convey.
You will need to remove (or at lest detension spokes) in the bent
area(s). Using a rubber mallet and blocks of wood as shown in the book
is the way to try. Be careful not to overshoot. Position the supporting
blocks on the outside of the rim under the area you are working and use
a wood block on the inside of the rim where you strike it in the
desired direction.
I agree with the telling statement in the book:
"Although some dents can be repaired satisfactorily this procedure is
generally used only to make a wheel usable until a new rim can be
obtained."
David Ornee, Western Springs, IL

Thanks.

--
B.B. --I am not a goat! thegoat4 at airmail dot net
http://web2.airmail.net/thegoat4/

In article <423be768.0@entanet>,
Zog The Undeniable <[email hidden]> wrote:

[...]

Quoted message said:

There is nearly always a bit of hop at the rim joint (whether pinned or
welded). Is the 1/5 there?

Nope. But one end of the 1/5 is at the valve hole.

--
B.B. --I am not a goat! thegoat4 at airmail dot net
http://web2.airmail.net/thegoat4/

If your bike shop can't dish a wheel.... You need to find a new bike
shop. fast.

1. If you knew how to do it right, you likely wouldn't have to ask.
Why aren't you taking it to a shop? Even if it's a beater wheel you
woudl only get charged a few bucks to get it done right? Is it
possible that your local shop sucks so bad that you won't even bring in
a damaged wheel to get repaired? That is just pathetic. (for them)

On Sat, 19 Mar 2005 21:13:00 -0600, "B.B."

may have said:

In article <423be768.0@entanet>,

Zog The Undeniable said:

There is nearly always a bit of hop at the rim joint (whether pinned or
welded). Is the 1/5 there?

Nope. But one end of the 1/5 is at the valve hole.

Be cautious when straightening in the vicinity of the valve hole; the
rim is weaker there for obvious reasons.

--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.

In article <[email hidden]>,

Werehatrack said:

On Sat, 19 Mar 2005 21:13:00 -0600, "B.B."

may have said:

In article <423be768.0@entanet>,

Zog The Undeniable said:

There is nearly always a bit of hop at the rim joint (whether pinned or
welded). Is the 1/5 there?

Nope. But one end of the 1/5 is at the valve hole.

Be cautious when straightening in the vicinity of the valve hole; the
rim is weaker there for obvious reasons.

Yeah, I took it out for a ride today to see if the hop was a problem
in its current state. It's not--I can't distinguish between it and
bumps in the road, so I'm leaving it as-is. I loaded up my bike with 50
lbs of tools and 160 lbs of me and took a 10-mile ride on these crappy
roads to see if the wheel would hold up under that and it was just
dandy, so I'm leaving it as I now have it. It should hold together
until I get to my new job/home and have money to buy new wheels.

--
B.B. --I am not a goat! thegoat4 at airmail dot net
http://web2.airmail.net/thegoat4/

In article <[email hidden]>,

bikeguy11968 said:

1. If you knew how to do it right, you likely wouldn't have to ask.

That reasoning kind of defeats the purpose of participating in rbt,
as far as I can tell. I've been straightening this wheel and others for
a while now using information I picked up in here. You'll note that my
question was a specific one, not simply a wide-open, "How do I tune a
wheel?" I could have experimented, but I figured I'd ask to save a
little time.

Quoted message said:

Why aren't you taking it to a shop? Even if it's a beater wheel you
woudl only get charged a few bucks to get it done right? Is it
possible that your local shop sucks so bad that you won't even bring in
a damaged wheel to get repaired? That is just pathetic. (for them)

There are three bike shops reasonably close to me. One I'm not sure
is even in business anymore as they never answer the phone and it was
closed both times I drove by. Out of the other two, one comes off as so
stuck-up I wouldn't be surprised if they refused to work on my bike
because it contains no carbon fiber and I don't speak Italian. The
third is just full of idiots and every attempt to "get it done right"
through them has required excessive waiting and I had to go back and
redo it anyway. The last time I bothered going there I just wanted a
solid axle in place of a QR axle that broke regularly. I was going out
of town, dropped it off, a week and a half later I came back and they
still hadn't done it. The guy went and did it while I waited--was way
too tight and so far off-center I had to pull it apart and when I did I
noticed they hadn't bothered to even clean out the old grease when they
assembled it. Before that was a botched headset and a chain with a very
stiff link.
So no way am I going to bother with any of them again. Besides, I
got my wheel straightened out just fine on my own without spending any
money. As a bonus, after putting some more work into my bike I'm
slightly more interested in riding it than I would be if I'd had them do
it. After all, I do like to work on my bike as much as I like to ride.
I hope that covers it.

--
B.B. --I am not a goat! thegoat4 at airmail dot net
http://web2.airmail.net/thegoat4/

It saddens me that customer service and mechanical skills have become
so lacking that regular civilians feel the need to become completely
self sufficient.

are knobbies mounted? if so that's a no feel situation with knobs
taking the abuse.
also cancels out this fact-the saveable bent rim when tightened way
beyond the elysium field equal spoke torque final result tends to self
heal over 0ne or more additional truings following a hundred or two
hundred more miles
consider the bent rim/wheel goinmg down the road on high pressure tires
and more or less true that is acceptable without excessive wear to the
wheel's components-takes a pounding just like an experienced craftsman
beating it gently with a plastic hammer.
and lo! the rim does go back toward being true without the excessive
torques to drag it over there!
the equal torque concept is available only for the gifted, lucky or
experienced-25% +/- is more likely.

before this slides out of sight
to resurface later
mark the spokes overtightened
and replace when the next spoke breaks
caws now those spokes are next after.

I guess this means that people are not supposed to enjoy working on
their bike unless they own a shop and are solely motivated by money.
Perhaps if the industry was more welcoming to those who enjoy doing it
yourself prices wouldn't be so out of control and more people might
become motivated to ride. It would not mean the collapse of the
industry either, ever go to a Home Depot or Lowes store? The reason
those stores are booming is people like the do-it-yourself idea.

I am working on upgrading/repairing a road and mountain bike. I have
gone to local bike shops and the ones that don't fuss or try to tell me
that I would be better off not working on it and bringing it for less
money, I walk/run out of. Those that support my hobby (not just riding,
but working on it too) I will support. The current shop I go to, I even
make sure to only talk with the sales/mechanic that understands I am
willing to pay more to do it myself.

Here is something to consider: Since your motivation is money, the next
time a customer wants to work on their own equipment, help them. You
just might find out you will make more money selling tools, parts and
supplies to an eager amateur mechanic than only a bike to a frustrated
want-to-be.

bigsky

bikeguy11968 said:

1. If you knew how to do it right, you likely wouldn't have to ask.
Why aren't you taking it to a shop? Even if it's a beater wheel you
woudl only get charged a few bucks to get it done right? Is it
possible that your local shop sucks so bad that you won't even bring in
a damaged wheel to get repaired? That is just pathetic. (for them)