Italian, JIS and Reverse-Italian Lacing: The Tangential Conventions and When They Matter

The three ways to arrange a crossed wheel, why one workshop prefers Italian, and the real case for the "wrong-looking" reverse-Italian — with links to the original posts.

Once you've decided on a crossed (tangential) wheel, there's a second choice most builders make without thinking: how the leading and trailing spokes are arranged through the flange. The conventions are Italian, JIS and reverse-Italian, and they're not interchangeable. Here's how one workshop weighs them, with the source links. "Right" is the drive side; a spoke laced head-inside-the-flange is an inpoke.

1. The three conventions

Italian and JIS are the two standard ways to lace a crossed wheel; they differ in how the inpoke and outpoke spokes are arranged relative to the drive direction. Reverse-Italian is the mirror of Italian — often assumed to be a mistake, but, as below, a deliberate choice on plenty of factory wheels.

Sources: Nomu Lab #618, #396

2. Why the workshop prefers Italian

For a crossed front wheel, the workshop's stated preference is Italian. The reasoning is consistency: it dislikes lacings where the inpoke direction ends up different on the left than on the right — which is what JIS and reverse-JIS do. By that measure, reverse-Italian is more acceptable than JIS, because it keeps the inpoke direction consistent. (When a wheel does get laced JIS, it's usually for a specific practical reason — on one track build, it was so that a flipped rear and the front would keep the same rim-label-to-valve relationship.)

Source: Nomu Lab #618 — Why JIS was chosen

3. The driving spokes

To see why reverse-Italian exists, you need the idea of the driving spokes. When you push the pedals, the hub twists forward and the spokes carry that twist to the rim — but the work is done mainly by the spokes pulling in the drive direction (the "leading" spokes). Campagnolo's own explanation credits only those spokes with transmitting the force. So the leading spokes are the ones that matter for drive efficiency, and in principle you'd want them as close as possible to the line directly under the rim.

Source: Nomu Lab #396

4. Split-flange hubs and reverse-Italian

On an ordinary flange — call it a same-axis flange — the leading and trailing spokes both leave from the same circle of holes. Some hubs (older ZIPP, several Shimano designs) use a split-flange, where the leading and trailing spokes leave from clearly different positions. That lets the designer place the leading (driving) spokes nearer the hub centre — closer to under the rim — for drive efficiency. The lacing that results reads as reverse-Italian.

Source: Nomu Lab #396 — On wheels that look reverse-Italian

5. The durability case for reverse-Italian

There's a second, practical argument the workshop makes for reverse-Italian on a rear — even a rim-brake rear, which is why some American factory wheels (PowerTap, ENVE) lace it that way. On a normally-laced (JIS/Italian) wheel, chain-drop damage and rear-derailleur-jam damage land on different spokes. On reverse-Italian they land on the same spoke — and chain-drop damage mostly hits the hub flange rather than the spoke, so the spoke takes a lighter hit overall. Concentrating the two damage modes onto one spoke, more gently, is a defensible design choice.

A side note the workshop is keen to make: the claim that "a tied-and-soldered wheel can't be trued" is nonsense — a wheel can be re-dished and even rebuilt with tying in place, so the lesser task of truing is obviously possible.

Source: Nomu Lab #7811 — Reverse-Italian has a point