A wobbling wheel problem can be caused by just loose wheel bearings. That's the easily part. If it's the rim is warped a bit bond to be a traditional bike with aluminum wheels that has been used like a donkey. Often one of the main causes do it yourself (DIY) back yard mechanics or owners attempting to replace missing spokes themselves.
An important detail loading the rear wheel is the rear wheel drop out. Traditional bikes have a step axial recesses rear wheels ride and secured in. Step angles can't cut it when carrying loads. They allow a fair amount of twisting forces that take it's toll on the rear wheel eventually bending the drop out itself.
A more balanced rear wheel drop out design has been developed for electric bikes past onto traditional bikes. The axial recesses is not angle led. It's more like a vertical hook. Specific cargo carrying capacity almost as a box. This is latest in cycle frame technology allowing carrying strength.
High tensile stainless steel alley frame and wheels is added for strength. They need to be for the weigh of the latest in electric bike craze right now with the extra weight they have top carry. If not electric they are at the very least back packer adventure touring and city commuter bikes. The vertical rear wheel drop out hook designs are strong and sturdy making the bike resilient ideal for personal owner loading. The vertical drop outs can do many miles loaded like a donkey for many trouble free years. If you are into loading your bike like a donkey it is better to forget the buckled aluminum wheel and tradition drop out frame bike replacing with a proper drop out suitable and heavy duty stainless steel alloy wheel adventure touring bike.
The traditional drop out design under heavy loading spokes tend to break off at the heads on the hub flange. Incorrect spoke replacement can cause distortion of aluminum rims during truing an important detail for novice DIY mechanics. The key derail points being the spoke heads in the hub flange, spoke crossings and spokes udder and over each other.
When it comes to truing aluminum wheels they can be a pain. By observing carefully all bike wheels will show you an important detail of alternating inward and out outward pointing spoke heads round the circumference of the hub flange. One is inward, the next one out, then the next one in then the next one out. Then, reputedly round the circumference of the hub. The second detail each side of the wheel the drive and opposite sides of every wheel.
Truing an aluminum rim by spoke tension it is a mistake to tighten spoke one at a time. It only time buckles rims creating twists and high and low spots which a pain to straighten out if aluminum. When replacing a missing aluminum rim spoke observe the spoke head pattern of your wheel threading the new spoke head direction according to the in and out head pattern. Keep the spoke heads uniform throughout the circumference of the hub flange. An important detail in replacing a missing spoke is in observing which side the missing spoke is. For rear wheel observe the drive and opposite sides. All said in done aluminum sensitive to distortion it is better better to replace the whole wheel with a stainless steel alloy wheel.
At the same time you should have observed a spoke crosses a spoke head. Tracing the spoke on one side crosses another spoke father up. Then another. You should have also observed going under and over pattern. Insert the replacement spoke according to the cross pattern. A important detail the spoke should be the same length as the the other spokes. To short or two long by millimeters cause aluminum rim distortion problems.
Notice another important detail depending on your bike, racing bike wheels are commonly 2 cross. The cross start at crossing the head on the flange commonly crossing 3 spokes. Strong cargo bike carrying capacity wheels can be up to 4 cross. Observing the wheels of a new bike you will observe this persistent pattern an ideal model your own bike wheel should be.
note another important detail. There is no gaps when crossing because the spokes are crossed over and under each other. This is the wheels strength. It is why they are so sturdy. As the wheel rotates each crossing under and over support each other from flexing. Gaps allow this to happen braking off at the head right at the hub flange. As a new bike wheel tells you thread any replacement spoke tucking under and over each other.
One of the consciences of a distorted rim causes the rim strap directly on the rim under the inner tube to miss align the tire bead not fitting the rim properly. The consequences is a distorted tire we feel as a hopping when we ride our bikes.
If a replacement spoke to short or to long is ignored will cause a bow in the rim when adjusting the spoke tension pulling other corners out of shape compromises. When this happens truing the circumference of the rim is but impossible with spoke tension alone.
It is possible to true with out a truing stand with the tire and tube removed the rim reassemble in upside down bikes. Rim brake bikes the brake rubbers make reasonable reference side to side wobble guides
Bikes that have no rim breaks a jerry-rigging piece of string tied across the front fork for front wheels or for rear wheels across the rear wheel drop out stays across the rim edges is a helpful reference guide. Move the rim round passing across the stretched across string. With no dips and rises we can clearly see the rim moves side to side of the across the string.
If there is bumping rises it is mistake to try to take out tightening one spoke at a time. This only makes it worse. Fixing rises is tricky. Move the rim to where the rise begins. Dab a bit of paint on the spoke to mark it. This insures you'll find it. An important detail is to keep noting which side of the rim the spoke the spokes are. With rear wheels check either the drive or opposite side spoke. Unfortunately without some form of guide this kind of meathead is at risk of creating a savvier side to side distortion. It's tricky to avoid.
Tighten the marked spokes only. Ignore all others. Don't wrench tight, Just a couple of turns at a time.
Check the whole rim alignment against the string. Adjust the two marked spokes again checking the whole rim alignment again. Repeating a couple of times takes out the rise. Then you can adjust the side to side wobble. Once again keep noting which side each spoke is.
When you move the rim round the stretch out string finds a point where the rim moves to one side. Loosing spokes will pull back centralizing just as tightening. Keep observing which side of the wheel the drive or opposite side spokes are.
If truing a rim in bike there is a couple of important details that shouldn't be overlooked. One is your eye coordination view of the straightness of the hub in the front forks or rear wheel drop out stays is aligned dead straight otherwise you will be truing the rim with a cockeyed wobbling mounted wheel that can cause truing difficulty. Depending on the wheel there danger of creating dips and rises between spokes.
Applies to bikes with no external rear wheel gear cluster bikes. When you reassemble the chain tight you will experience as if there is dragging feeling as if the bike is heavily under powered slowing you down. Fairly sloppy yet it can't come off the front chain wheel or rear wheel sprocket you will experience freedom of peddling movement in the peddling. Correctly loose chains theses bikes feel light and powerful. Anyway, tight chains stretch the links warring out the chain links.
Anther important detail if crescents (Revolving or shifting spanners as they are also known) is all you've got they are crude and bulky. Sloppy jaws have no grip slipping and sliding from the loose slack movement burring round the nipple shanks beyond loosing every time. The best revolving spanner are expensive. Jaws that are no sloppy have a sold grip when you tighten the nipple. Never the less it is not recommended because of the awkward bulkiness of theses tools.
An option is a spanner of a firm fit. Low cost ones tend to be low tensile (softer metal) strength that tend to warp the jaw wider in time starting to show signs of slipping round the nipples rendering the tool useless. You will be forever replacing nipples that won't work anymore. Expensive top of the line spanner is best grip because of high tensile hardened steel quality strengths want bend wider without damaging nipples.
However proper spoke keys are available at bike shops. For best results the same proper fit on the shanks of each nipple as the latter applies. Sometimes even cheep ones start to show signs of bad grip problems because the shank is low tensile opening out the in the key sliding and damaging your spoke nipple shanks.
An important detail when replacing ruined nipples screwdriver option must have a sold grip on tight nipples. Incorrect size does much damage to the slit as as a slack shifting spanner jaw does to the nipple shanks rendering it useless. When these things happen you can forced to cut the spoke to replace the whole spoke just because of a ruined nipple. What ever method used gather the tools and spokes you need before you start.
Youtube has plenty of video clips with lots of helpful tips you can follow visually. In your search engine type in the key words youtube truing bicycle wheels. The clips assume no rim distortion compromise's. There are clips that show you how to true a wheel with out a truing stand.
A sign the rim has been compromised between the spokes you end up and creating up and down bumping. It is inevitable a replaced spoke that is too short causing the low spots. You may find a obvious sign some spokes appear to be to short in one corner. It is enviable the opposite corner will appear to long. To short is a sign of a dip. To loose a sign of to long. It's time to eye ball check between spokes and look for incorrectly installed spoke. You will find there is nothing you can do with any more spoke tension apart from making things worse ignoring spokes that are to short.
In the youtube clips rim brake rubbers are handy to uses as a guide. Observe how the rim runs between them. Youtbe clips show tips on how jerry rig with plastic zip ties as a substitute refence if your bike has no rim brakes.
With experience you can tell witch side of the rim needs to be straightened by the revolving the rim between rim break rubbers or your make shift guides. (As according the the string and youtube clip tips).
The key to lateral side to side wobbling is to loosen or tighten keeping an eye on the radial up and down adjustment that pulls the rim to the left or right centering between the guides automatically adjusting rise and dip spot areas automatically.
The following are technical issue keys to replacing spokes to building wheels. In building on any salvaged rim always double check all spokes are exactly the same lengths and eye ball check between the spoke nipple holes are not compromised first.
Wheel size.
As explained in some yuotube clips wheel size is stamped on the tire wall. X is the width of the tire including the tire rim height. A dress making tape measure across the tip to tip of whole the tire will confirm imperial inches and the flip side in metric.
Mountain and commuter bike tires are commonly 26 inches for adults and 24 for the younger set. The metric equivalent to 26 inch is 700mm (or 70 centimeters if you like) called 700c. 26 inch and 700c rims may look identical but comparing a 700c tire will be a little smaller than the imperil 26 inch meaning the spokes are different lengths between wheel sizes.
It is a common mistake getting mixed up between a 26 impearl and metric 700C rim assume looking the same size at first glance. Novices often end up (including any spokes salvage from another wheel) struggling with metric 700C tire onto a 26 inch impearl rim and vice versa, a 26 tire onto a 700C rim respectively. They are not the same wheel and tire size. One is metric the other imperial.
The width of the tire is also an issue.
An important detail is to observe the width that includes the height of the tire wall. We can all see in bike shops have a variety of tire sizes in both impearl and metric. When replacing a tire take particular note of the original tire's width and tire wall height details. Racing road bikes are the thinnest and smallest rim height. There are common commuter bikes both standard and electric. The wide cargo bike tires and the widest of them all are mountain sport bikes.
Budget tires (the cheep ones) tend to be low kilometer ware and tare lasting. Seems seem to become unstuck. The most important detail are not puncture proof. Mere thorns will puncture brand new ones, while expensive tires that has done many kilometers still in good order takes a huge nail to puncture those tires. The more expensive the more kilometers of ware and tear quality tolerance and designed with puncture proof property in mind.
Double check with a tape measure the diameter of you bikes tire to that of the diameter of the rim. 26 inch and 700C may look the same size at first glance but the 700c rim is slightly smaller. If you have striped down rims you can see this by comparing the the two sizes. Picking up a new spoke or tire from a bike shop quote not only the tire diameter but also the width. If you are not sure take some tape measurements of the original rim to the shop personal or use the original spoke.
Another meathead of determining what spoke length is required measure one of the original wheel's spokes with a tape measure from the spoke nipple in the rim to the spoke head in the hub flange. If you have a selection of savage spokes you've salvaged from other wheels compare your spares and use the one that is the same length.
Paying close attention the spoke arrangement is the key in getting the wheel running smoothly. An important detail if you have a striped down hub or a brand new spare count the number of spoke holes round the hub flange. The number of spoke holes counted one side equals the same number the opposite flange doubled equals the total number of spokes of the whole wheel. For 18 18 holes on the left side and 18 on the right equals the total number of spokes of the rim is a detail worth knowing.
Bike shop racing bike displays each side of the hub flange can be as little as 5 or 6. Common commuter and mountain bikes not very common at 16 commonly 18. Cargo bike carrying capacity hubs can be as much as a total of 20 each side. The spoke holes represent one side doubled the total number of spoke spokes of the whole wheel an example of the perfect symmetry to bicycle wheels.
Counting the total number of spokes divided in half is the key to the number of the hub. And vice versa the number of spoke holes doubled the total number of spoke holes required by the rim.
The following is tracing the spoke pattern of a good wheel as a model, the key to bicycle wheel mechanics.
One of the most important details in rebuilding wheels is the slight dish like curve of the hub flanges. If you use a striped down rear wheel hub as a model to using a brand new spare or if it's your own bike is all you've got observing the hub flanges you can make out one side may appear slightly dished while the other side may look dead straight. Depending on your bike there is the potential for both sides could be dead straight or both sides dished. Correspondingly there are rims with alternating staggering spoke holes in some rims.
What ever you find with your bike is one of the most important details of getting the wheel running smoothly.
Bike parks illustrate clearly the importance of this. Viewing back wheels square on, you will see various dished like appearances to each wheel. You will encounter allsorts of bikes single, double and triple front chain wheels, 1, 5, 6, 7 or 8 rear sprocket sets. Statistically math's works out to 7 possible arrangements can be seen.
Aligning square on closely at a rear wheel specially, you will note the details of some bikes the spokes look dished out and some flat inwards. You will note a variation of some gear cluster sides may look flat, while the opposite side may look dished. Others both sides may look flat while others both sides may look dished.
An important detail to note is the gap between the gear cluster and opposite side of the rear wheel drop outs. There is 4 possible hub arrangements in three statistical variations. There is the obvious, slightly obvious and not so obvious dished like appearance to each wheel. It all depends on model manufacture design. A quick glance at the front chain wheel churnings and the rear wheel gear cluster set can tell you straight away the gaps are controlled by the speed of the bike.
Looking at striped down hubs or new spares as a model if you can see the shortest hub can only accommodate a limited number of sprockets telling you a 10 speed hub. The longest length up 8 with the variations between. Thus with experience one can learn to tell the important difference between a 10, 12, 15,18, 21 to a 24 speed hub.
Viewing the rear wheel of bikes at bike stands as a model the important detail of the hub flanges revealing rear wheels guided between the drop outs stays are perfectly even clearances each side of the drop out stay accommodating the number of rear wheel sprockets. You will observe either gear cluster or opposite sides look corresponding flat or slightly dished on one side or dished both or flat both sides aligning the hole wheel dead center between the stays all due to the slightly dish curve of hub flanges.
Observing the important detail of the the stays under the brake bridges plenty of even clearance both sides of the tires you can check with rulers. Dissembled hubs show the slightly curved inward or dead straight gear cluster opposite side flanges give those dished like appearances to rear wheels. Some hub flanges will make the whole wheel appear flat or dished both sides. Doing arithmetic statistics tells us there is up to 6 possible combination to be seen.
Operating on the principle of the details when rebuilding a wheel from salvaged spare is to to aim for the key to wheel building success.
Another important detail you will see a prefect symmetrical pattern from the spoke nipples in the from rim to the hub flange. Tracing a spoke to the hub flange you will find every second spoke nipple is the opposite side of the hub flange. They two alternate in a prefect symmetrical pattern.
If you take an outward pointing head tracing to the spoke to the nipple in the rim counting five along and tracing the fifth spoke back to the flange you will observe the next inward spoke. The same is
true with inward pointing heads all round the rim in a perfect and regular symmetrical pattern.
Using new bike or a known good wheel as a model novices can learn what rebuilt wheel should be.
Every inward and outward pointing spoke heads are on the same sides of each hub flange. If you take a pair of spoke nipples and trace the spokes down to the hub flange will either be inward or outward pointing that side of the wheel. A good model to work from will help you determine the right way to reassemble a new spoke.
Choosing the right length is a couple of options. If you have the old one removed you can measure with a tape measure or the spoke void left left in the rim or one of the other spokes.
Alternatively if you have spare spokes laying round check them against the gap. You can either
Compare them to the other spokes or line up the head lining up with the spoke hole in the hub flange lining up the nipple thread to just under the nipple hole of the rim.
A important detail to understand it is a mistake to use a spoke protruding though rim nipple hole or to short. To long you run out of threat not able to tighten. To short pulls bulges in the rim helping to put more of a wobble in the rim.
Just right the spoke head lined up with the spoke hole in the hub flange with the tip of the thread just under the rim hole. Following new bike wheel patterns to aim for when replacing a new spoke. That's the easy part.
The hard part is proper spoke tension. Testing spoke tension on a known good or new bike tells you what spoke tensions should be. It is a mistake to tighten spokes in line one after the other. That only makes it easy for novices to create badly distorted rim wobble. It only mangers to twist over the rim more.
The bike upside down resting on the set and handle bars a spinning wheel shows the slightest rim wobble. It is often deceiving as a up and down and side to side bumping in the rim at the same time.
Aware of the way the hub flange arranges the spokes nipples in the rim alignment is a important detail in adjusting out the rim wobble though spoke tension.
The proper way to true a wheel is a proper wheel truing jig professional bicycle shop mechanics use. Wheels are mounted using the axial in a frame between a pair of precision pin points. It is a lot easier than using the frame of your bike.
It is possible to true to some extent in bikes. A handy feature of rim brake bikes are ideal used as make shift reference guides. Other bikes make it more compacted. The only make shift reference available aligning between the front forks for front wheels and rear wheel drop out stays for rear wheels. It takes a great deal of experience and skill.
However make shift guides can be fitted to the front forks or rear wheel drop outs with simple broom handle storage clips taking the place rim brake rubber pads of rim brake bikes. Mount the clip aligning the a reference point for each side of the wheel.
An important detail using only the tools you've got cheep shifting revolving crescent spanners destroys nipple nipple crisp. Not only is there no room to turn the nipples the cheapness of the jaws is are to slack specially worn out slipping on the nipple shanks unable to get a firm grip butching up the shank giving you moving spoke nipple problem movement heart aches. Expensive top of the line worth a lot of money cressets are much better but there is still the great risk of room and ruining spoke nipple shank.
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