Spoke Wheel Building & Truing

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F YOUR BIKE has spoke wheels, thenyou need to know how to maintain,repair and true them, its as simple asthat. This article will cover the basicsas illustrated with a dirt bike wheel,

but the same principles apply to street hard-ware. Note that were using a tube-type rimbecause most spoke wheels are like that.Less common tubeless spoke-wheel appli-cations, like those on the BMW GS, theAprilia Capo Nord and various trails bikes,look a little different, but the fundamentalsare identical.

Second, you need a way to get yourbikes wheels up off the ground, at least oneend at a time. If youre changing compo-nents, the wheels obviously must be

removed. But if youre just giving yourwheels a truing tune-up, they can stay onthe bike.

Third, youve got to have some way ofmeasuring very small deviations in theradial and lateral movement of a turningrim. Professional truing stands allow forrotation of a wheels hub in a fixed plane,and include an adjustable armature formounting a runout gauge or for using asa static indicator all by itself. However,these professional grade tools are ratherexpensive (from around $200 to upwardsof $600), and you can probably improvise

something adequate for a whole lot less(see sidebar).

A fourth necessity, one that isnt partic-ularly expensive, is a quality spoke wrench.Throw out that pot-metal piece of junk thatcame in your bikes tool kititll do moreharm than good. Spoke nipples are smallbut require significant torque. And if its adirt bike youre working on, the nipplesyoull be twisting are probably made of soft,

easily deformed aluminum, and they mayresist turning due to corrosion or excessivetension. Either way, a precise, tight-fittingmatch between the wrench and nipple isabsolutely necessary to avoid rounding offand ruining the nipples flats and crushingit against the spoke threads. You can usuallypick up a much better-fitting version at yourlocal motorcycle shop for under ten bucks.But know the exact size you need, as thereare half a dozen in common use.

Finally, because the procedures involvedare extremely repetitious; use tiny incre-ments of adjustment; and require a meticu-lously systematic approach, you will needabove-average patience and a setting inwhich you can concentrate for an extended

period of time.

Starting From ScratchIf youre replacing only a bent rim plus a

broken spoke or two, begin by taping thespoke overlaps together to keep everythingin alignment. However, if major disassem-bly is your plan, and you are replacing yourhub, perhaps a full set of spokes and/or rimwithout altering the original spoke pattern,you should begin by studying your wheelslayout before taking anything apart. Spokesare rarely identical; often with four distinctconfigurations per wheel, some with the

heads angled differently because they arepositioned inside or outside a flange andtherefore slightly different in length as well,and/or the hub flanges are different sizes orconfigurations, necessitating perhaps twomore different lengths and angles. The dis-tance from the head to the bend is known asthe throat length, which varies dependingon the thickness of the flange.

Notice, too, how the spokes leave the hub

in different directions; which row of hubholes points its spokes clockwise, andwhich counter-clockwise? Look to seewhere the spokes cross one another, andhow many make up a repeating pattern (themost common arrangement is a sequenceof four, comprised of one inner and oneouter from each hub flange). If you have adigital camera, take several pictures fromdifferent angles for quick reference later.Or, make yourself a sketch. Spending a fewextra minutes at the beginning may saveyou much frustration later. And if yourebuilding a wheel with all new aftermarketcomponents, you may be given a com-pletely different spoke pattern from yourbikes original design, so consult your sup-

plier for instructions. If youre only replac-ing spokes, you can ensure the reproductionof the existing configuration by simplyreplacing each one you remove beforeremoving the next one.

In the example shown, were keeping thestock hub, and installing aftermarket stain-less steel spokes and an aluminum alloyrim, all made by Excel. The goal wasincreased strength, so the replacementpieces are sturdier than stock (however, theweight difference in this particular applica-tion is negligible). And while you cantappreciate it in black-and-white photos, the

new rim is also flashier, with a deep goldanodized finish. Also, we chose Excelsspline drive nipples, which provide astronger surface for wrenching than con-ventional square nipples, and theyre madefrom steel instead of aluminum.

The trickiest part is getting everything inplace without scratching your new rim.Start by placing your disassembled hub flatin the center of the rim. Hubs with large off-

How-To..

SPOKE WHEEL BUILDING & TRUING by Mark Barnes

Left: The stock wheel prior to disassembly. Note that the nipples have Allen heads at their ends, a ccessible only with the tire and tube removed, but

some wil l have slots for conventional screwdrivers instead. Center: Choose your weapon. From top: Stock tool kit spoke wrench, spline drive wrenchincluded with new spline- drive spokes; the m ulti-size spoke wrench from Rowe, which covers all six comm on nipple sizes; Fasst Companys spoke

torquewrench, with spline drive head. Right: A little penetrating lubrication can make nipple rem oval a painle ss process. Now theres a thought!


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sets may require special measures, such as

setting the rim on a couple two-by-fours inorder to get its centerline at the midpointbetween the two hub flanges. Youll be lac-ing one hub flange completely before turn-ing everything over. Thread the first spokethrough its hole in the hub, and then insertits threaded end into the rim, taking care tochose a hole angled upward (toward the sideof the hub youre currently working on). Ifyoure working on a very fancy wheel, therim for which has holes cut at more thantwo angles (left and right), youll need tomake sure that the spokes entry anglematches the rim holes angle precisely.

(You can check this by simply inserting apencil through the hole and confirming thatthe spoke lines up with it.) Now, afterputting a drop of lubricant on the threads toinhibit corrosion, screw a nipple onto thespoke tipbut only a couple turns. Thiskeeps the spoke from falling back out of therim, but leaves you maximum room to pushthe rim away from the hub in other direc-tions to give subsequent spokes the clear-ance they need for easy insertion.

On the wheel shown, we found it worked

best to do all the outer spokes (those fur-thest from the axial centerline) first, andthen insert the inner ones. This may be dif-ferent on your wheel, depending upon thespoke pattern and clearances. You mayhave discerned the easiest sequence duringthe disassembly process, or you may haveto do some trial-and-error testing at thisstage. The main point here is that youshould not have to struggle to get all thespokes in place. If you find yourselftempted to force a spoke into position bybowing it or its neighbor, theres almostcertainly a better way. Remove a few and

try a different order. Be sure to leave thecorrect number of holes on the wheel openbetween spokes as you insert them.

Once all the spokes are in place on onehub flange, turn the wheel over and repeatthe process on the other side, and when youcomplete this phase of the job, give yourselfa pat on the back; the (relatively) hard partis over. You now have a floppy, jangly thingwith a roughly circular shape that will soonbecome an amazingly sturdy and geomet-

rically precise piece of hardware.

Circular LogicChances are, the rim youre working with

is currently very close to perfectly round.Your job is to keep it that way while tight-ening all those spokes, any one of which iscapable of distorting your rims shape ineither of two dimensions. You see, spokesare incredibly strong devices. Their realstrength is in the form of pulling (tension),rather than pushing (compression), eventhough that may run contrary to intuition.Spokes do not support the hub from under-neath so much as suspend it from above.

Think about it. Which would be stronger, asingle spoke extending from the hub down-ward to the rim, or that same spoke extend-ing upward? Would it be easier to bend thespoke below or tear the spoke above? Nowits obvious, right? Tremendous tension canbe brought to bear on the rim by tighteningspokes, enough to deform a very strongloop of steel or alloy into a wobbly potatochip shape. You can avoid this painfullyembarrassing fate if you heed our advice.

Left: Notice how the inner row of spokes on the far flange point clockwise, while the outer row points counter-clockwise. Also, see how their heads arerecessed in the near side of this hub. Center: The partially installed spoke illustrates its specific features: The head, throat length (distance it pass-

es through the flange) and angle to match the direction to the rim. Right: The old wheel, half-way disassembled.

Left: A perfect fit betwee n spoke wrench and nipple makes the job easy and (Center) prevents this from happening. Not only is this nipple rounded,

its also become crushed against the spoke threads, making it doubly difficult to remove. Right: Once loosened topside with a wrench, nipples can be

unscrewed easily from the other side.

How -To


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Start by getting all the nipples equallysnug. Again, you may have to figure out

whats possible by trial-and-error. On ourexample, we found we could get all the nip-ples tightened to the last visible thread oneach spoke before any significant tensionwas applied to the rim. We arrived at thisknowledge by meticulously tighteningevery spoke on the wheel the same numberof turns, time after time. Time consuming,yes, but ultimately it saved time becausewe didnt end up with one side of the rimpulled in closer to the hub than the otherside before we even started the truingprocess. Remember, the definition of a cir-cle is a line with all points equidistant from

a central point and lying in the same plane.Its better to avoid pulling the wheel out ofround from the beginning, instead of cor-recting deviations afterwards.

Now, with all the nipples threaded thesame distance up on the spokes, the wheelwill be much closer to rigid, but thereshould still be no tension among the spokes.When you lift it up, it should hold its shape,but still jingle just a tiny bit. However, youmay notice thateven with all the nipples

perfectly the same on their respectivespokes, some are closer to the rim than oth-

ers. This may be because of variations inspoke length or their placement radially onthe hub. For example, if all the outer spokes(furthest from the axial centerline) are alsoa little closer to the edge of the hubs flange,they will protrude further through the wheelunless they compensate for this differencein hub mounting position by being slightlyshorter than the inner spokes. If you findsuch a discrepancy between spoke sub-groups, carefully adjust the looser ones insmall increments, just as you did with allthe spokes at the start of this tighteningprocess, until they have just as little slack as

the spokes that were initially closer to snug.NOTE: Those of you who are only per-

forming a tune-up on your wheels, ratherthan building them, should join us here.Because spokes will tend to loosen over themiles, you should try to identify the loosestspokes by spinning the wheel and bouce-ing a wrench off the spokes. The loosespokes emit a dull dead sound whentapped, while those that are still tight emita bright ping. To get all the nipples close

to snug before precise truing, snug the loosespokes first.

If you decided to spring for a truing stand,position your wheel in it now. If you areusing a different method, secure the wheelon its axle (or axle-substitute) and set upyour runout detector (dial gauge or pointerarmature) to check radial runout (distancefrom the hub center to the outside edge ofthe rim). Next, check the lateral runout,(side-to-side deviation). If your spokes areall evenly snug (but not floppy), this willtell you if your rim is way out of true, all onits own. A new rim should be nearly perfect,and small deviations in a used rim may becorrectable during the truing process.

Now The Fun BeginsWell address radial runout first. With

your detector in position for this measure-ment, determine where the rim is furthestaway from the hub. This will be the highzone if your detector is at the top of yourwheel or the low zone if its at the bottom.Youll need to tighten the spokes in thatzone to pull the rim there closer to the hub.Start with a spoke in the middle of the

MOTORCYCLE CONSUMER NEWS JANUARY 2006 29

Left: The new pieces, left, are visibly m ore substantial than the stockers they replace. (Dont be fooled by the narrower threaded section on the Excel

spoke; its shaft is thicker than OEM.) Right: The first row of new spokes, with nipples l oosely attached. Right: Notice the even spacing along the rim.

Left: One row of spokes finished. The wheel begins to take shape. Center: Detail of the spokes lea ving the hub. Notice how the holes point only partwaytoward the spokes target on the rim; the spokes bend (right at the holes edge) completes the necessary angle. Right: Halfway done; heres the wheel

with one side (flange) of the hub laced.


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offending zone and tighten it in a smallincrement, such as a half-turn. Tighten thenext spoke on both sides of it slightly less,maybe a third of a turn. Tighten the nextspokes away even less, perhaps a quarter-turn. Finally, tighten the next spokes out(now three spokes away from the first) aneven smaller fraction of a turn. This methoddistributes the influence of your effortsevenly, so that it doesnt change the lateralrunout, instead of causing an acutelyfocused shift that is likely to create otherirregularities and send you chasing your tailin an endless series of corrections. Next,

find the low spot and reduce spoke ten-sion in a similar pattern.

This is the kind of thing you will developan efficiency-boosting feel for with prac-tice. But novices should make small adjust-ments, even though that may mean makinga lot of them. It will still take far less timeto do it right the first timegraduallythan to get intoand then back out ofacycle of overtightening/overcorrections.

Now recheck the radial runout. Is it still

within your margin for error? If not, repeatthe previous steps and check it again. Keepdoing this until your wheel shows less radialdeviation than two millimeters.

Now, its time to switch the angle ofattack, although the battle tactics remain thesame. Set your runout detector to check thelateral deviation and rotate your wheel tofind the place where it is furthest from theaxial centerline. For the sake of simplicity,well call that the lateral high zone, and inthis example lets say youve found it onthe rightside of your rim right next to therim lock hole. To pull it back toward the

center, youll need to tighten the spokes onthe leftside in that zone while loosening thespokes on the rightside. Start with the leftspoke closest to the middle of the high zone,and tighten it a small amount. Proceed toits next left neighbors on both sides, andtighten them a little less. Continue to spreadyour influence to the outer edges of the highzone, reducing the amount of rotation asyou get further away from the middle, andtightening only the spokes on the left side.

Repeat the same technique while looseningthe right side spokes.

Recheck the lateral runout. Next, deter-mine the lateral low zone (the right side)and make the necessary adjustment, byloosening in the same way. Repeat thisprocess until the rim has less lateral devia-tion than two millimeters. Note that itspossible by making all adjustments to onlyone side (for instance, always tightening theleft side, rather than tighening/loosening)to make your wheel perfectly even in theleft-right dimension, but with the rim cen-terline offsetlaterally to one side of the

hubs axial centerline.For more precision in achieving this

alignment of centerlines, depending on howyour wheel is mounted for this operation,you may be able to flip it around in yourwheelstand or take measurements on bothsides from positions exactly the same dis-tance from the hubs centerline; a straight-edge laid across the flanges might allowthis. Note, however, that all hubs are notnecessarily symmetrical in their axial

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How -To

Left: This truing stand from K & L Supply is a good value; it can be used as a balance stand as well. Notice the armature stored on the right-side sup-

port. Center: Here the armature is set to radial runout. Notice that the reading is taken from a horizontal surface on the rim, rather than at the edge of

the flange. This keeps variations in flange shape out of the equation. Right: The armature has been set to measure lateral runout. Notice that the read-

ing is taken at the base of the rim flange to minimize the effect of irregularities in the flanges shape.

Left: Here, a dial caliper is set to measure left-right runout. Center: During the truing process, each spoke is turned only a small amount at a time.

Many tiny adjustments get the job done more quickly than larger moves that upset the wheels shape elsewhere, or set up a cycle of overcorrectionsthat deforms the rim. Right: This simple yet effective truing setup required only a pair of clamps connected by an articulated stalk, about five bucks at a

local hardware store. One end grabs the rear workstand, the other end holds a piece of metal stock up next to the rim.


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Spoke Wheel Building & Truing