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Bowen's 7 Simul (5 Memo): No-Flip 7 Simul for 7sf Solvers Who Hate Tracing

You can solve Clock with 7 Simul Flip, but Tommy's 7 Simul feels like too much — too many dials to trace, too much mental arithmetic under pressure, and the memo just won't stick in 15 seconds. This method is for you.
It's a no-flip variant of Tommy's 7 Simul with a different pin order, built as the easiest bridge from 7sf to no-flip 7 Simul. It memorizes the same 5 numbers as Tommy's, but the total memo is shorter: 19 terms instead of 22.
Four of the five memo formulas are identical to Tommy's, and they keep Tommy's relative order: M2, M3, M4, M5 here are Tommy's M1, M2, M4, M6. Only M1 is new — it replaces Tommy's 7-term M5 with a 4-term one.
The pinky count is the same (2 bottom-dial moves), and it costs 2 extra pin changes (8 vs Tommy's 6). All memo coefficients are ±1, so no memo ever needs a doubled value.

Method

In 7 simul, we use a fixed pin order to solve the clock.

Then we memorize 5 numbers based on modulo arithmetics of 12 (e.g. 5 = -7, 3 + 8 = 11 = -1, 5 + 8 = 13 = 1, 2 - 3 = -1, 2 - 8 = -6 = 6).
You will have the flexibility on how to memorize them. But we recommend several common strategies:

  1. Remember numbers as-is in your native language.
  2. Encode numbers into A for 1, B for 2, ..., K for 11.
  3. Combine both, e.g. 1-6 with native language, and E for 7, D for 8, etc.
  4. Similarly, but instead of native language, use a language (e.g. Japanese/Korean/Chinese) which has low syllabus count for numbers.

The memos, in the order you compute them (uppercase = front face, lowercase = back face):

  1. M1: (R - DR) + (l - u). 4 terms. Used in step 1, top-right dial. (New — replaces Tommy's 7-term M5.)
  2. M2: c - d. 2 terms. Used in step 2, bottom-left dial. (Same as Tommy's M1.)
  3. M3: U - UR - L - r. 4 terms. Used in step 2, top-left dial. (Same value as Tommy's M2, dr - r + U - L, via the constraint dr = -UR — but reads front-face UR instead of back-face dr.)
  4. M4: d - r. 2 terms. Used in step 3, top-left dial. (Same as Tommy's M4.)
  5. M5: UL - L - R + DR + u - c + d. 7 terms. Used in step 5, top-right dial. (Same as Tommy's M6.)

After memorizing these 5 numbers, we will solve the clock with the aforementioned pin order.
Each time, you will adjust two dials simultaneously (unless the adjustment required is 0), either based on the memorized number, or based on intuitively matching two clock faces (similar to flip method).

The best way to illustrate this method is to use a demo example. We use the same scramble as Tommy's 7 Simul so you can compare the two methods move by move.

Now the clock is solved!

Tip: you don't need to memorize M2. M2 = c − d is only 2 terms, and it's used at step 2 — the second move of the solve. Just glance at the back-face dials c and d at the end of inspection, hold the number for about 2 seconds, and use it at step 2. That leaves only 4 numbers to actually memorize.

You may also check out 7 Simul Simplified (4 Memo) for a memo-order trick on Tommy's pin order.