Lurelip — Fishing lure lips (crankbait bills) | lurelip.com
6 modelsDT series depth ratings covered
4 ftshallowest published rating, DT04
16 ftdeepest published rating among the six compared, DT16
16 ft (5 m)deepest published rating among the six compared

Depth starts at the bill

Lurelip — Fishing lure lips (crankbait bills) | lurelip.com

A crankbait runs where its bill sends it. The length of the bill, its shape, the position of the line tie and the speed of the retrieve all change where the bait sits in the water column. This guide explains how a bill creates diving force and how to read manufacturer depth ratings without treating them as guarantees.

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Bill shape · published depth · shoreline testing · tuning
How a crankbait's bill sets its diving depth, wobble and running line.

At a glance

Bills and depth in numbers

16 ft (5 m)deepest published rating among the six comparedThe Rapala DT16 is published to reach 16 feet, about 5 metres, in its manufacturer's depth chart — the deepest of the six compared models. Actual depth depends on your line and retrieve.
4 ft (1.2 m)shallowest published DT ratingThe Rapala DT04 is published to run at 4 feet, about 1.2 metres. This is the shallowest rating in the DT series covered here.
10 ftverified published model rating, DT10Rapala publishes the DT10 to dive to 10 feet. A short shoreline retrieve only checks tracking and roll — assessing actual running depth requires a proper cast or troll in known-depth water with your line.

Published depth chart

Rapala DT published depth ratings. Manufacturer figures for comparison; actual depth depends on line and retrieve.
ModelPublished depth (ft)Published depth (m)Note
Rapala DT044 ft1.2 mShallowest DT rating published
Rapala DT066 ft1.8 mBalsa body, polycarbonate bill
Rapala DT088 ft2.5 mBalsa body, polycarbonate bill
Rapala DT1010 ft3 mBalsa body, polycarbonate bill
Rapala DT1414 ft4.3 mDeep-rating DT model
Rapala DT1616 ft5 mDeepest DT rating among the six compared
Rapala DT published depth ratings. Manufacturer figures for comparison; actual depth depends on line and retrieve.

How the bill creates diving force

The bill is a flat surface that water presses against as you pull the lure forward.

A crankbait's bill sits at the front of the lure at an angle to the direction of travel. As you retrieve, water pushes against the bill's face. That pressure has two effects: it pushes the nose down and it resists forward motion. The downward component is the diving force.

The strength of that force depends on how much of the bill is presented to the water. A larger face at a given pull speed catches more water and presses harder. That is why bills differ in length and shape across models.

The force is balanced against the lure's buoyancy and the pull of your line. How that balance settles determines the running depth for your particular setup. Line weight and retrieve speed shift the balance, so manufacturer published depths are comparison figures, not fixed outcomes.

You cannot predict metres from the bill's angle alone. Two bills at the same angle but different lengths will not dive the same. Read a published rating for a specific model, then test that model with your line.

  • Bill face catches water as the lure is pulled
  • Water pressure pushes the nose down — this is the diving force
  • Buoyancy and line pull balance the force to set running depth
  • Line weight and retrieve speed shift the balance
  • Angle alone does not predict depth; length and shape matter too

Terms

Bill
The flat lip at the front of a crankbait. Water pressing on it creates the diving force that pulls the lure down.
Diving force
The downward push created when water pressure acts on the bill face as the lure is retrieved.
Published depth rating
The manufacturer's stated running depth for a specific model, in feet or metres. A comparison figure, not a guarantee for your line and retrieve.
Line tie
The eyelet where your line attaches to the lure. Rapala's tuning advice involves a tiny adjustment of this eyelet opposite the direction the lure veers.
Shoreline test
A short retrieve at the water's edge to check whether a lure tracks straight and rolls cleanly. It does not determine running depth — that requires a proper cast or troll in known-depth water.
DT series
Rapala's Dives To line of balsa crankbaits with thin polycarbonate bills, published at depths from 4 ft to 16 ft.

Questions anglers ask

What does a crankbait bill actually do?
The bill is a flat surface at the front of the lure. As you retrieve, water presses against it. That pressure pushes the nose down and creates the diving force. The balance of this force against the lure's buoyancy and your line pull sets the running depth.
Can I predict depth from a bill's angle or length?
No. Bill shape alone cannot predict metres. Two bills at the same angle but different lengths will not dive the same. Use the manufacturer's published rating for the specific model, then confirm the actual depth with your line and retrieve.
Why doesn't my lure reach its published depth?
Rapala states that line weight and retrieve or trolling speed affect the actual running depth. There is no universal correction percentage. Test with the line you plan to fish: retrieve at slow and fast speeds and note the depth range you observe.
How do I fix a crankbait that runs sideways?
Inspect the bill and body for damage first. Then make a tiny adjustment of the eyelet opposite the direction the lure veers and test again. The improvement must be visible on the next retrieve. Do not move the eyelet fore or aft to change depth.

How this reference was assembled

Every measurable claim comes from manufacturer-published ratings or from a testing procedure the author created. Published depths are stated as the manufacturer's figures in feet and metres. Bill behaviour is explained qualitatively. No universal sink rates, correction percentages or angle-to-depth rules are asserted.

Sources

Sources list the manufacturer pages and articles consulted for published ratings, bill materials and tuning advice.

How the billcreates divingPublished depths:what the DT chartTesting a crankbaitat the shorelineTuning a crankbaitthat runs crooked
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