joejack951

I didn't take quite the beating on my lightweight commuter bike frame thread as I thought I would so I'll push my luck with this new lightweight commuter wheel thread

Here's the wheel build plan:

Front Hub: American Classic Disc 130
Rear Hub: American Classic RD-205S
Front Rim : IRD Cadence (VSR?)
Rear Rim: IRD Cadence VSR
Front Spokes: DT Revolution (32)
Rear Spokes - DS: DT Competition (16)
Rear Spokes - NDS: DT Revolution (16)
Nipples: DT Swiss Alloy
Weight: 1430 grams (claimed) [not bad for 32 spoke, 3 cross wheels with a disc front hub]

A few questions:

1. AC's website and SpoCalc really disagree on the hub dimensions. Can anyone confirm AC's numbers? I trust them more than SpoCalc as SpoCalc's descriptions are a bit vague so it's tough to determine if the correct hub is even listed.

2. For the Revolution spokes, is it a consensus that I should use spokes 1mm shorter than spec'd by SpoCalc? I haven't run that numbers in DT Swiss's calculator yet but I've heard it does this automatically.

3. Am I making any bad assumptions by thinking that using the VSR rim on the front as well as the back would even out spoke tensions with the disc hub? I realize that it's probably unnecessary but if it does work then I might as well do it, right?

joejack951

So I ran the numbers both on DT Swiss's website and SpoCalc. They agree for the non-VSR rim but DT Swiss doesn't have an option for an offset spoke bed rim so I could only run those numbers in SpoCalc. The difference is only a few tenths of a millimeter though.

For L/R tension, however, the front goes from 76% to 84% and the rear from 67% to 76%. I'm liking the VSR front and rear idea even more now.

Al1943

I like your choice of spokes and nipples.

joejack951

I also looked at building these wheels using DT RR1.1 rims and DT 240S hubs or Chris King hubs. The cost and weight increase was significant with either of those options compared to the American Classic hubs.

AEO

Aren't AC hubs designed to eliminate major dishing found in most wheels?
honestly, I don't think you need off center rims with AC.
for the front, since you are using a disc hub, assumably disc brakes, you'll want comp spokes on the left side.

but, let's say you go with off center rims...
if the specs are what they say they are.
which is CFL=30, CFR=20 for RD205
and CFL=24.5, CFR=32.5 for disc 130
then there's only around 0.8mm of difference in spoke length left and right.

so let's say you go with an off center rim, which is around 3mm offset, giving
CFL=27, CFR=23 for RD205
CFL=27.5, CFR=29.5 for disc 130
ending up with 0.3mm difference left and right and whatever compensation for 2.0/1.8, 2.0/1.5 DB spokes.

with no off center rim, I think you'll end up using the same length spoke left and right since the revo stretch more than comp.
with an off center rim, you might end up getting 1mm shorter revo, compared to the comp.

joejack951

I haven't read anything to the effect that AC hubs eliminate major dish. Per SpoCalc, there's still a significant tension difference left/right using a standard rim.

I know it was discussed a little while back about using Revolution spokes on a wheel with a disc hub. It didn't seem as though there was an consensus that it was a really bad idea. Do you have experience with that setup?

AEO

nope, just assuming since disc brakes do the reverse of the drive side.

joejack951

Well I'll let everyone know how it goes. Thanks for the input.

joejack951

In my excitement to order parts for the build, I managed to reverse the lengths of my spokes for my rear wheel accidentally ordering 290mm for the NDS and 291 for the DS when it should have been the other way around. SpoCalc said 291.1 for the NDS and 290.5 for the DS so I figured I'd be ok.

Nope. As I started bringing up the tension on the DS, I quickly ran out of the spoke length. I had barely 50 kgf on the spokes and I couldn't turn some of the nipple at all. LBS to the rescue with their Phil Wood spoke cutter which quickly knocked off 18 black DT Comp spokes in 289mm length (requested, though actual length is closer to 290). I'm just bringing up the tension now and have plenty of room left to reach 100 kgf like I was originally shooting for.

Even better news is that DS/NDS tension is close to 90% (so far) using the off-center rim. The tension is even better for the front wheel where I also used an off-center rim because of the disc hub.

Weight on my often unreliable scale seems to average about 640g for the front wheel and 790 for the rear (no skewers or tape) which is right at my estimated weight. Now if only my seatpost would arrive I'd actually have a chance at riding these wheels this week on the new frame (Pedal Force CX1).

joejack951

Some final numbers:

I kept the tension on the low side given the weight of the rims. I stopped at 85 kgf (average) on the disc side in front and 90.5 kgf (average) drive side rear. L/R tension in front was an impressive 92% (SpoCalc said 84%) and 78.5% (SpoCalc said 76%) in the rear. My initial tension balance numbers were a bit off as the dish wasn't quite there yet.

The bike should be rolling next week so I'll get to evaluate how those Revolution spokes feel. I'll be sure to report back again.

Al1943

I would crank up those tension numbers quite a bit. Low tension will lead to broken spokes. Trust me on this.
Do the final lateral truing and dishing with the tires and tubes fully inflated to riding pressure. This will make some difference in the rear wheel dish and possibly in the lateral true.

Al

joejack951

What sort of tension would you recommend? I based my numbers on the recommendations for the American Classic 350 Sprint wheels that I have on another bike. AC recommends 90-110 kgf for them.

I learned on my first wheel that mounting a tire can make a big difference. I got a ping or two attempting to pry on the Continental GP 4 Season tires (hint: the 28mm tire size will not take a 28-32mm tube). I had to touch a few spokes on the front and rear to retrue.

Al1943

I don't know enough about your particular wheels but I go to about 120-130 kgf on driveside rear spokes and 110 on front spokes. And I have gone higher on the DS rear. The problem with modern multi-speed wheels is getting enough tension in the non-driveside rear spokes due to the tension differential needed to center the rim. I use a Park TM-1 tension meter and my kgf numbers are based on their conversion chart which may be in question.

joejack951

With the offset rim and Revolution spokes in the rear, I don't think I'll have an issue with those spokes going loose, but only time will tell. I built the wheels the way I did to minimize the tension differential and utilizing the extra stretch of the Revo's to minimize the chance of slack spokes. On a heavier weight rim, I might consider going to 120-130 kgf (I'm using a Park TM-1 as well) but I'm hesistant on a 390 gram rim. I'm not a super lightweight but I'm far from a clyde at 165 lbs.

This is my first full wheelset build so I know I'll be learning something the hard way. And I don't the learning experience to include my face meeting the road. Anyone else care to comment on the tension numbers?

Al1943

I wouldn't be worried about the spokes coming loose.
A few years ago I built a set of wheel with all Revolution spokes, Open Pro rims, DT alloy nipples, Chris King hubs. In less than 200 miles two of the non-driveside rear spokes broke in the "J" bend at the hub, a sure sign of insufficient tension. I don't know what the tension was but I thought it was plenty. Then I bought the tension meter and cranked up the tension on all of the spokes, 157 kgf on the DS rear. Have not had a broken spoke since then and the wheels still look new after several thousand miles.
I quit using Revolutions on the driveside rear because they stretch too much under high tension. My primary bike has DT competition spokes on the DS rear and Revolutions on the rest. The rims are DT RR 1.1 single eyelet, 415 gr. I also weigh 165 lbs.

Al