Another day, another wheel (and so on).
I took in a rear wheel built with an Ambrosio Montreal rim from a customer.
I have the same rim myself, but in silver. This one's hard anodized color, but it's not a particularly light rim, so it's fairly stiff even in silver and can take quite a bit of tension.
HB-7600R 36H NJS hub with Star aero spokes in 8-cross Italian lacing.
Judging by the magnetism of these spokes, they're decent Starbright—though I initially thought they were reproduction Starbrights.
The Italian lacing is used because, even though the hub has threads on both sides, practically only one side gets used.
The fact that the threads on the other side are only clean around the sprocket portion suggests a single-speed freewheel body was installed there previously.
I suggested that if there's even a 1% chance of using the other side's threads in the future, we should consider switching to JIS (Japanese Industrial Standard) lacing when rebuilding.
The reason for rebuilding in the first place was that the wheel felt a bit loose, and the customer initially wanted the rim changed. But looking at it closely, the rim wasn't really bad, so I thought I'd just re-tension it.
But the spokes were too long, making re-tensioning difficult. So I had to disassemble it completely, cut the spokes slightly, then rebuild.
The spokes are long because they're NJS-approved aero Starbrights based on a #15 specification. Reproduction Starbrights, except for special orders, only come in #14 base and aren't NJS-approved.
NJS-approved aero Starbrights come only in 305mm length, which is perfect when building a 36H 8-cross wheel with an HB-7600 hub and an Araya 16B Gold rim. Montreal has a slightly higher rim profile (smaller inner diameter) than the 16B Gold, so using NJS spokes as-is makes them too long.
The rim is pulling toward the sprocket side. If you can't center a wheel even when the hub has no hop, spokes are flat and can be gripped with a spoke wrench, then it's impossible to properly build anything more difficult than that.
Tighten it up a bit more. Well, maybe whoever built this has never laced a wheel with anything other than the 16B Gold. That rim is extremely delicate—frankly, it's weak.
↑This lockring seems to be installed backwards...
I removed it. The lettered side was facing inward, so it was indeed backward. The absence of beveling on the corners was a tip-off that something was wrong.
I disassembled the wheel. Based on the sprocket tooth count, I decided I could remove the spokes without having to remove the sprocket first—taking a shortcut. But if that hadn't worked, removing the sprocket from the hub shell alone would be impossible (it's only possible if you're willing to clamp the hub shell in a vise and accept damage), so I'd have had to do a temporary build.
I pulled out just the non-crossed spokes
cut them to length, then cleaned them. I did the same with the crossed spokes afterward. I separated the crossed and non-crossed spokes so I wouldn't change their relationship during the rebuild—it's my standard practice.
Built it.
8-cross JIS lacing. I'll do the spoke bracing later.
Cleaned the hub too.
It's centered.
The final crossing isn't perfectly rigid, but it's definitely tighter than before the rebuild.
On a different note, this is a diagram from a distributor's material showing how chainrings and sprockets wear. The idea is that chain roller contact points wear both the front and back of the tooth evenly, but I really don't think that's possible...
The cleaned small sprocket from this rear wheel happened to show exactly the kind of wear pattern that illustrates my point.
I took in a rear wheel built with an Ambrosio Montreal rim from a customer.
I have the same rim myself, but in silver. This one's hard anodized color, but it's not a particularly light rim, so it's fairly stiff even in silver and can take quite a bit of tension.
HB-7600R 36H NJS hub with Star aero spokes in 8-cross Italian lacing.
Judging by the magnetism of these spokes, they're decent Starbright—though I initially thought they were reproduction Starbrights.
The Italian lacing is used because, even though the hub has threads on both sides, practically only one side gets used.
The fact that the threads on the other side are only clean around the sprocket portion suggests a single-speed freewheel body was installed there previously.
I suggested that if there's even a 1% chance of using the other side's threads in the future, we should consider switching to JIS (Japanese Industrial Standard) lacing when rebuilding.
The reason for rebuilding in the first place was that the wheel felt a bit loose, and the customer initially wanted the rim changed. But looking at it closely, the rim wasn't really bad, so I thought I'd just re-tension it.
But the spokes were too long, making re-tensioning difficult. So I had to disassemble it completely, cut the spokes slightly, then rebuild.
The spokes are long because they're NJS-approved aero Starbrights based on a #15 specification. Reproduction Starbrights, except for special orders, only come in #14 base and aren't NJS-approved.
NJS-approved aero Starbrights come only in 305mm length, which is perfect when building a 36H 8-cross wheel with an HB-7600 hub and an Araya 16B Gold rim. Montreal has a slightly higher rim profile (smaller inner diameter) than the 16B Gold, so using NJS spokes as-is makes them too long.
The rim is pulling toward the sprocket side. If you can't center a wheel even when the hub has no hop, spokes are flat and can be gripped with a spoke wrench, then it's impossible to properly build anything more difficult than that.
Tighten it up a bit more. Well, maybe whoever built this has never laced a wheel with anything other than the 16B Gold. That rim is extremely delicate—frankly, it's weak.
↑This lockring seems to be installed backwards...
I removed it. The lettered side was facing inward, so it was indeed backward. The absence of beveling on the corners was a tip-off that something was wrong.
I disassembled the wheel. Based on the sprocket tooth count, I decided I could remove the spokes without having to remove the sprocket first—taking a shortcut. But if that hadn't worked, removing the sprocket from the hub shell alone would be impossible (it's only possible if you're willing to clamp the hub shell in a vise and accept damage), so I'd have had to do a temporary build.
I pulled out just the non-crossed spokes
cut them to length, then cleaned them. I did the same with the crossed spokes afterward. I separated the crossed and non-crossed spokes so I wouldn't change their relationship during the rebuild—it's my standard practice.
Built it.
8-cross JIS lacing. I'll do the spoke bracing later.
Cleaned the hub too.
It's centered.
The final crossing isn't perfectly rigid, but it's definitely tighter than before the rebuild.
On a different note, this is a diagram from a distributor's material showing how chainrings and sprockets wear. The idea is that chain roller contact points wear both the front and back of the tooth evenly, but I really don't think that's possible...
The cleaned small sprocket from this rear wheel happened to show exactly the kind of wear pattern that illustrates my point.