Bicep slicers are brown and black belt only in IBJJF, while neck cranks such as the can opener and twister are illegal there.
Treat the bicep slicer like other advanced compression locks under IBJJF belt limits.
The IBJJF Technical Fouls & Illegal Moves table — published with the Rule Book on the IBJJF Books and Videos page — marks the bicep slicer through purple belt. Adult brown and black belts may use it. The finish is off-limits for white, blue, and purple IBJJF competitors even if the entry appears from triangle, omoplata, or armbar scrambles.
Official ADCC Championship rules list any arm bar, shoulder lock, or wrist lock as legal, which covers the bicep slicer. Compression through the upper arm can become dangerous quickly. In training, fold slowly. In IBJJF competition below brown, abandon the illegal finish and move to a legal arm attack or positional score.
Can openers and twisters are the common high-intent examples people ask about.
IBJJF marks spinal locks without a choke in every Illegal Moves column. Can openers and twisters applied as neck or spinal cranks are illegal in IBJJF at every belt.
Official ADCC Championship rules list the can opener and the twister as allowed. The same page bans neck cranks that trap both shoulders and put downward pressure on the neck. Nearby chokes and truck control can still be useful when the crank itself is banned.
- Can opener: IBJJF-illegal neck crank from front headlock or turtle
- Twister: IBJJF-illegal spinal lock from the truck
- ADCC championship rules list both as allowed, with a separate two-shoulder neck-crank ban
- Always separate positional study from illegal finishing pressure
Finish with legal chokes
From front headlock, prioritize guillotine, darce, and anaconda mechanics instead of yanking the head.
Know when compression is allowed
Bicep and calf slicers may be legal later by belt or ruleset. Until then, treat them as awareness topics, not competition weapons.
Key Takeaways
- IBJJF marks bicep slicers illegal through purple; legal for adult brown and black.
- Can openers and twisters are IBJJF-illegal neck or spinal cranks in every division.
- ADCC championship rules allow those finishes and separately ban some two-shoulder neck cranks.
Further Study
Official IBJJF Rule Book (v6.0) and Technical Fouls & Illegal Moves downloads. Confirm your age, belt, and gi/no-gi column.
Official ADCC legal techniques, illegal techniques, scoring, and time limits.
Compression lock mechanics and belt-based legality.
Neck crank awareness with safer legal alternatives.
