Wheel Truing: Getting Rid Of Hop?
(PeteCresswell)
never had do deal with hop.
But now I've got about 1/8" of hop in a wheel I just laced up.
Not having a lot of luck getting it out.
Is there a methodology beyond the obvious?
--
PeteCresswell
D'ohBoy
Gah - 1/8" is pretty big. Is it a larger area (like 1/3 of the rim,
peaking at 1/8") or a smaller area (like at the weld, like a poor
junction of the hoop)?
Cuz the possible solutions vary based on that answer.
Regards,
Peter
landotter
than a dip.
Ron Ruff
tension the obvious way. If not then loosen the spokes first. If the
hop is truly in the rim and not caused by tension variations, then
take care to minimize the tension variations necessary to keep it true
as you bring the tension up.
Bill
or more spokes in the middle of the hop are looser than the rest.
Reduce the tension on all the spokes somewhat, by the same number of
turns. Then squeeze pairs of spokes together near where they cross.
This will permit you to easily ascertain which spokes are tighter, and
which are looser, than the rest. Equalize the tension of all the
spokes until all the pairs feel the same when you squeeze them. Then
true, while not exceeding 1/4 turn at a time on any spoke. As you true
and find runout and out-of-round, squeeze spoke pairs again,
tightening the ones that are looser than the others and loosening the
ones that are tighter than the others, again not exceeding 1/4 turn at
a time, until they are all at the same tension. Then true again. I
have found that squeezing pairs together is a very accurate way of
determining the spokes' relative tension.
thirty-six
Yes. Set all nipples showing the same amount of spoke thread, then
when tightening up, work around wheel by tightening every 7th spoke
(on 36 or 32, every 5th for 28). Done this way, the tension can be
brought up quickly without problems using the same number of turns
(usually 3 or 4) for each spoke, finishing with 1/4 turns.
Stephen Bauman
You're going to have to go back and rebuild the wheel. Assuming that all
spokes and nipples are identical go back to where all the nipples are
threaded equally on the spokes (1 or more threads showing). The wheel has
some rigidity - spin it. Did the hop disappear? If not, then you have a
bad rim. Most likely if the problem is at the joint.
If there are no hops, then the trick is to tighten the spokes without
introducing a hop. If you have to tighten each spoke several turns, go
one turn at a time and go several turns of the wheel to get the spoke
tension you want. As tension increases, you may want to make that half
and then a quarter turn and go around several times.
Stephen Bauman
thirty-six
Even when the rim is supplied distorted.
datakoll
side. idea is bringing the long side back toward the hub while
allowing longer spoke lengths on the opposite side.
draw this shape(s) play with the idea in head and paper.
procedure here is marking hop with felt pen.
hold pentip against cleaned (thinner then CHOH) rim brake surface,
brace hand then spin rim.
see a circular felt tip mark against an egg shaped rim/hop.
mark thehop's outside-outside points then add a coupla spokes both
ways.
do the same for opposite side.
use the tape and count method.
divide number of tobe adjusted spokes in halh count to middle.
loosen/tighten-on the hop side from =middle spoke then two adjacent
spokes then 3-4 adjacent spokes...keep count/use magic tape from WAL
do the opposite side.
obviuosly, there are refinements to this eg tightening more in the
middle then less as you tighten to the sides.
loosen some first-the tightening needs room right ?
on the beach
La Paz
Jobst Brandt
> I guess I've been lucky with all my wheel builds to date but I've
> never had do deal with hop.
> But now I've got about 1/8" of hop in a wheel I just laced up.
> Not having a lot of luck getting it out.
> Is there a method beyond the obvious?
Yes, before someone made a too for that I found my own way but let me
suggest:
> From what you say, it seems only the sidewall (the bead) is bent.
> This is an easy one t fix if done with care. Use a large adjustable
> wrench (Crescent wrench) with which to clasp the bead and bend it
> back to its normal shape as well as you can. To but a flat section
> into the arch of a rim takes a hard landing on a hard tire. That is
> harder to repair but can also be done. There is a rim straightener
> tool:
> but before I got one of these I loosened the spokes in the area and
> hung the wheel on a 2x4 beam and hung on it. That worked well.
Jobst Brandt
datakoll
FURTHER THOUGHTS ON ORION’S PENIS FROM THE GROUP TWO WHEEL BUILDER
:
Know the shape, ‘floret’ ? RIMs sometimes ‘floret.’
Best start with the big lump when faced with a ‘floret’work.
Most hops removed here are redone on the bike thru sighting the
revolving tire surface to the chainstay brace.
Some hops are best relieved as written prior but also loosening a few
spokes at the acceptable curve just outside the hop end.
Which leads to ‘hop: terminal method one:’ loosening all exceptin’ the
hop spokes which are off course tightened.
And sometimes staring over with the bare rim on a truing stand. First
torque applied to only the marked hop or more likely hop(s) that is
seat all nipples then advance the hop nipples ¼ or ½ 0r…turn ahead of
all other nipples.
If you analyze the rim on truing stand in the ‘advance torque
nipples’ method then you will develop a more comprehensive loosen
tighten the egg shaped hoping rim as an approach to the floret rim.
Soon the radial true will mesh with the lateral.
La Paz
AMuzi
A little flower? It's in Milano:
http://www.italyby.com/fiorella/pages/faciliti.htm
Or this one?
http://www.vintagevelos.com/Fiorelli1940.html
--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971
datakoll
Seams I used an incorrect word....
what's the word for image as a sine wave strung over a circle's
circumference ?
a rose wheel makes the drawing right likona dollar bill ?
(PeteCresswell)
>work around wheel by tightening every 7th spoke
>(on 36 or 32, every 5th for 28).
That one's a "keeper".... never thought of that before, but it
makes perfect sense: once one knows that all the spokes are the
same length, minimize the number of spokes involved until the
number of turns is known.
--
PeteCresswell
Jobst Brandt
> I guess I've been lucky with all my wheel builds to date but I've
> never had do deal with hop.
> But now I've got about 1/8" of hop in a wheel I just laced up.
> Not having a lot of luck getting it out.
> Is there a method beyond the obvious?
Yes, before someone made a tool for that I found my own way but let me
suggest:
From what you say, it seems only the sidewall (the bead) is bent.
This is an easy one t fix if done with care. Use a large adjustable
wrench (Crescent wrench) with which to clasp the bead and bend it back
to its normal shape as well as you can. To but cause a flat section
thirty-six
Dunno what it's called, but I sure reddened my forehewad and palm when
I realised what i did.
Jobst Brandt
>> but before I got one of these I loosened the spokes in the area and
>> hung the wheel on a 2x4 beam and hung on it. That worked well.
> Have you done that on alloy rims without causing failure soon after?
> We used to use those tools and techniques all the time back when all
> the kids rode steel rim bikes, but I always have fears of alloy
> cracking after such a treatment.
I got no steel rims. What makes you so suspicious of aluminum? These
are extruded aluminum rims (Mavic, Torelli, Fiamme, etc.) not hard
anodized or heat treated. As I said, in earlier times I manually
removed flat spots by loosening spokes in the affected area and
hanging my weight on the wheel supported by a 2x4 in the middle of the
flat spot.
Jobst Brandt
(PeteCresswell)
> tightening every 7th spoke
>> (on 36 or 32, every 5th for 28). Done this way, the tension can be
>> brought up quickly without problems using the same number of turns
I've got it pretty much perfect now.
Strangely, the "same number of turns" approach (that I've always
used...) did not work. I would up with tight spokes and loose
spokes.
So I got out the tensiometer and tried for the same tension. Took
about 3 trips around the wheel, but I finally got them all pretty
much the same.
At that point the wheel was laterally and vertically true: no
wobble and no hop. However some spokes were all the way to the
top of the nipple, and others were several turns down in the
nipple and the wheel was off-center.
Loosened one side a half turn, tightened the other side a half
turn... and it was centered.
I didn't want to re-lace the wheel, so I never removed the spokes
to confirm they were all the same length (they were custom-cut)
but it seems to me like one explanation would be that the spokes
varied a mm or two in length.
--
PeteCresswell
datakoll
opposite side's nipples more then tighten or pre tighten the hop
nipples from cenetr outward.
La Paz
As Ghandi said " yo''l see more of yourself in the people at road's
end than at its beginning."
the sky is blue like when I was 10.
thirty-six
That would do it.