[jwh321 offline]

I've just finished truing the wheels on my bike -- again. As a preface, let me say that my wheels are run of the mill wheels that come on the typical Trek bike. They are neither "bad" wheels, nor are they really "good" wheels. Just wheels.

I am a wheel-builder from many years back, but I have built only road wheels.

My standard OEM type wheels do not stay true for long. As I was truing them (I have an old Park truing stand -- still the best around in my opinion) I found that the spokes were not particularly tight and the spoke tension is well below what I am used to on my road wheels.

Questions: Do mountain bike wheels, in general, run much lower spoke tension than road wheels? Do mountain bike wheels, again in general, seem to require more attention to keep them true than road wheels? And finally, are there any "tricks" that any of you have mastered to keep the wheels running straight and true for long periods.

My bike weighs just over 28 lbs and is seldom subjected to much abuse of any kind, but it does see some off-road use. It has 180mm 6-bolt disks front and rear and full suspension. I weigh right around 200 (before dinner).

[element22]

Well the techniques are the same.

Just make sure to prebend the spoke to make sure there is no slack and run about the same tension as road wheels...Of course to me it is all feel and how you like the wheels to feel..I tend to run my tension high and like the stiff feeling wheel....While others run them a bit softer..I don't really bend wheels myself nor do I snap spokes..

When building wheels I go around once or twice each time I am tensioning the wheels grabbing the two near parallel spokes on either side of the wheel and give them a good squeeze to release any wind up....

[Seriously_Tho offline]

As a wheel builder you probably know most the tricks. Tension is about the same as a road wheel but if you're tensioning by ear the shorter spokes will sound different than the road wheels.

One trick I've used is putting a drop of boiled linseed oil on each nipple from the rim cavity side, it'll harden in about a week & prevent loosening. You can still break it free when truing.

[jwh321 offline]

That's a great tip. Thanks so much. I've about decided that my OEM wheels have very poor quality spokes and nipples. I bought a set of after market wheels -- not expensive ones, just entry level wheels, but they seem very well made.

Its my intent to disassemble the OEM wheels and put them back together with DT 15 straight gauge spokes. It looks to me like the hubs and rims are of acceptable quality, but the corporate folks cut some costs by buying poor quality spokes.

One other wheel building tip that I will share -- for those of us who are a bit anal, I ran a spoke nipple onto a spoke to lock it into place then I chuck that piece into an electric drill. I use it to "polish" the inside of each spoke hole to ensure that each nipple moves smoothly as it is tightened. I don't know if it has much impact, but I have some road wheels that I built in the mid-seventies that are still true and round so I figure, it can't hurt. I also slightly chamfer each spoke hole in the hun to ensure that the bends in the spoke have no sharp corners which could lead to fatigue in that area.

Myabe I'll post some pictures when the rebuild begins.

So far, I'm having a ball just building this bike. It has about 800 miles on it now and I'm finding its my "go to" bike when I just want to get outside and ride a bit. It'll go anywhere, and I've found all kinds of neat places to ride off road that I've never seen before. Its headed to Colorado for the summer and its going every place that the motor will allow.

[Seriously_Tho offline]

If you were building wheels in the 70's you had to contend with problems that don't much exist these days. I'm old-school too so I get it.

For instance we used to grease spoke threads b/c it made for better wheels even if they loosened a bit. Spoke threading & materials are so high quality now that it's unnecessary & hastens their demise. Same with reaming hub spoke holes - not a good idea anymore since flange tolerances are much tighter. Many can't sustain radial lacing because the manufacturing processes have changed.

Since you're enjoying it you may want to invest in a couple modern books to bring you up to speed on the little things that have changed. They aren't basic by any stretch & are a pleasure to read, some amazingly advanced tips. Try The Bicycle Wheel 3rd Edition & either of the Zinn mantainance books (rd or mtb).

[dgaddis offline]

Seriously Tho is right, you need to do some reading. A lot of things have changed since the '70s!

Spoke tension is dependent on the rim and hub. Stans NoTubes rims do not have eyelets, so they can't use as high a tension as rims that do have eyelets. The rim manufactuer should have their max tension listed on their website. And if you're building a wheels this toolis a very worth while investment, so you KNOW you have the right tension.

Tuning by ear will get you even tension on all the spokes, but you don't know what that tension actually is.

Take a look at this tech sheet (PDF) for DT Swiss MTB rims, their max spoke tension can vary from 1000N to 1200N, a 20% swing.

One other wheel building tip that I will share -- for those of us who are a bit anal, I ran a spoke nipple onto a spoke to lock it into place then I chuck that piece into an electric drill. I use it to "polish" the inside of each spoke hole to ensure that each nipple moves smoothly as it is tightened. I don't know if it has much impact, but I have some road wheels that I built in the mid-seventies that are still true and round so I figure, it can't hurt. I also slightly chamfer each spoke hole in the hun to ensure that the bends in the spoke have no sharp corners which could lead to fatigue in that area.

Removing material around the spoke holes in either the rim or hub is a BAD idea. Use linseed oil around the nipple head so it moves freely when building the wheels, then as the oil dries it almost turns into a glue. Use it on the spoke threads as well, for the same reasons. This was a trick I got, passed down by the best local wheel builder in town.

[jwh321 offline]

Great stuff folks -- thanks so much for sharing.

As a practical matter, I disassembled the front wheel last night and found exactly what you described. The no-name hub (the rear is Shimano) is very well manufactured, and There appeared to be little that I could do to improve the shaping of spoke holes.

The rims are another story. The "eyelets" that the nipples sit in appear to be haphazardly inserted. Some are full seated, others are tight, some are crooked. There is some serious "gouging" on the nipple heads that I removed. In short, there appears to be very poor quality control on these pieces -- new rims are on order.

The spokes are strange. While they have a very smooth black coating, they seem to be made of some sort of soft metal -- not very spoke-like, more like the metal in wire coat hangers. I also found quite a few that had rough threading, and without tension, the nipples fit loosely. I still intend to rebuild with DTs. And when I do, I have a handy-dandy Park spoke tension gauge hanging on my TS-2 to help with spoke tension. I also have an ancient, but still very good Campagnolo dishing tool. Do keep in mind, however, I make no claim whatsoever to being the world's greatest wheel builder. I'm always amazed when I'm done that they are still round. But I love doing it.

Also, interestingly enough, I came home from my latest visit to Barnes and Noble with "Zinn and the Art of Mountain Bike Maintenance" 5th Edition. Great stuff (and an amazing looking bike on the cover).

BTW -- although I built wheels in the 70s, I've continued to build quite a few in the intervening years so I do have some contemporary experience, but all of them have been road wheels. And we had non-eyleted rims in 1975, too.

[Seriously_Tho offline]

I think we all have a tendency to stay loyal to the techniques we learned originally even when no longer applicable. I just recently stopped greasing cables in the housing, a practice I should have stopped when cable housing liners became ubiquitous back in the 90's.

Enjoy your wheel adventures & the book!

[jwh321 offline]

The first thing that seems so foreign to me is to dish the front wheel (to accomodate the disk).

I'm so used to using the same size spokes on both sides of that wheel.

I'm also finding it interesting to see the differences in angles in t rear wheel that is dished less on the left side.

I'm having fun.

[dgaddis offline]

I'm having fun.

That's what it's all about man!

I'm looking forward to building another set of wheels one day. So far I've only done one set, and I've been extremely happy with how well they've held up. I haven't touched them since the initial build, and have ridden them hard for almost a year and a half now (most of that time on a fully rigid bike ) and they're still really true. The rear has a very slight wobble (maybe 2mm) but the front is still perfect.

It's a fun process, something everyone should do at least one. It can be frustrating though...I think it took me 4 tries to get the lacing pattern right on the first wheel