spoke torque

[jimmyg]

Does anyone know what the proper spoke torque is for standard R90s rims? (18" rear, 19" front, 1974).

I have the rims off doing tires and thought I would go through the spokes on my truing stand. I have a standard spoke wrench that I've used in the past, but have since picked up a Pit Posse Spoke Torque wrench.

I should also note that the spokes are stainless steel.

thanks,

jimmyg

[Bamboo812]

I've never heard of a specific torque mentioned, but I use the "musical note" method. If I tap them with a wrench, they should make a "tink" noise, and it is not the same on every spoke. If they make a dull sound, they are too loose... Do you know you must "set" the spokes, with a hammer and a drift, before the final tightening?

[jimmyg]

Thank You and yes, I have the spokes 'set' already.

[Duane Ausherman]

A torque wrench for spokes is useless, as there is no way to get them the same and have the rim round. The "tink" that Bamboo mentioned will be somewhat different as you go around for correctly tightened spokes.

I used a specially cut screwdriver for tightening. You may see it here http://w6rec.com/duane/bmw/spoke/8.JPG and you may learn more than you ever wanted to know about building BMW wheels here http://w6rec.com/duane/bmw/spoke/

I always loved tuning spokes and usually did it on the front counter of the showroom. Everybody was interested. I used a dial indicator. On the assembly line at the factory, that guy just used a pointer. It took him 7 minutes per wheel. I was impressed. He made it look boring.

As I got interested in motorcycles, I was told that building a wheel was black magic and only a few were in the hallowed club. It is just plain old science and anybody with patience can do it.

Sometimes I would "set" them a second time at what was the finish round. Sometimes I would find that a couple would have loosened up again.

[jimmyg]

Thanks so much for the information. Just finished a tire change on the bike. Both rims were nearly perfect, with just one spoke on the front and three on the rear, barely loose. Runout was perfect on both rims as well.

And I agree Duane. A few years ago, I decided to tackle wheel truing. It's frustrating at first but the 2nd, 3rd, 4th wheel, etc. go much better and you quickly develop a "feel" for it.

Much like when balancing your first set of wheels. You start to learn how much weight to add based on how fast the wheel 'falls' to BDC.

And FWIW, I did pick up a nice Pit Posse torque wrench. Just to have I guess..

jimmyg

[Duane Ausherman]

jimmyg and others, once a person gets a wheel balanced, or think that it is balanced, stimulate the wheel with a vibrator. I use my tool etcher for that purpose and I can get it sensitive down to one gram. A stable looking wheel will "take off" with some vibration applied.

For those saying that it isn't useful, I have this question, what problem is caused by it being too well balanced?

[Major Softie]

...stimulate the wheel with a vibrator.

Diane strikes again....

[Texer]

Duane - where on the wheel assembly do you apply the vibration with the etcher? I just balanced my rebuilt front and would like to add that measure as well. Btw I will have the axle riding on roller bearings for least resistance. - thanks

[Duane Ausherman]

I use the Marc Parnes balancer and love it. Sounds like you have something similar.

I just hold the vibrator against the bracket holding the two outboard wheels upon which the axle sits. I haven't ever had two vibrators to use, so can't say that one vibrator on each side is better than the single that I use.

It is also important to know how and where to put the weights for best results. By using BMW type spoke weights it is hard to split up the weight. The smallest is 5 grams. I like to get it closer than that. One should never require more than 15-20 grams to get the balance. If it takes that much, then the tire can be rotated to get it way down.

My method takes a lot more time, but often gets the balance with little or no weights. I have described it here before and I never put it on my website, so it may be lost info. We never trusted the paint mark on the tire. I hear that the paint mark is no more accurate today than back 88 years ago in my day.

I have seen 5 grams make the difference between a stable bike and a wobbler. I could go on for an hour.

[Texer]

Thanks Duane, I appreciate the reply and details and the balancer info. I will be rotating mine on the rim next - it used too many weights and all on one area of the rim (although did read as balanced). I used a home made setup with skateboard bearings.