Bicycle bolt torque references: units, ranges and the exact joint
Read the complete specification before recording a torque reference: distinguish N·m, N·mm, inch-pounds and foot-pounds, maximum from a range, and the exact receiving parts and preparation conditions. No tightening value is prescribed.
Published 15 October 2026 · OpenBikeFit
Same torque. Different numbers.
- N·m
- 4.00
- N·mm
- 4000
- lbf·in
- ≈35.40
Independent fictional unit exercise: 4.00 N·m = 4000 N·mm ≈ 35.40 lbf·in ≈ 2.95 lbf·ft. In contrast, 4.00 lbf·ft ≈ 5.42 N·m. No number here is a component specification or a wrench setting.
A maximum does not choose a target.
Separate artificial constraint exercise in N·m: A 4–6 and B ≤ 5.5 overlap numerically at 4–5.5 only after assuming both sources apply. A 6–8 with B ≤ 5.5 has no common value. Neither case supplies a target or approves an assembly.
Original reference ledger, not to scale or an installation drawing. Resolve exact joint, receiver, source, preparation and tool conditions. No tightening or physical work is performed.
On this page
- 01Start with the exact joint, not the nearest number
- 02Read the whole unit before converting a value
- 03A range, a target and a maximum are different statements
- 04Resolve the receiving-part conditions without inventing agreement
- 05Torque indication is not a direct preload measurement
- 06Preparation is part of the reference, not a universal recipe
- 07Multiple fasteners and procedure stages stay separate
- 08Check what the tool documentation actually covers
- 09Keep a source record that another person can follow
- 10Use the existing worksheet and workflow without bypassing their limits
Preserve the source, not a guessed target
Read the blank reference spaces
General paper procedure/reference spaces with your own supplementary notes. No dedicated torque fields, saved record or installation verdict.
Open toolBefore a bicycle adjustment, a torque marking can look like the missing answer: find the number, copy it and continue. That skips the most important question. Which exact connection does the number describe, in which configuration, under which instructions? This guide helps an adult read and retain that reference. It does not supply a tightening setting, authorise mechanical work or certify a finished bicycle.
You can complete this reading task without loosening a fastener, selecting an adjustment, starting a camera or creating a bike record. All numerical examples below are fictional interpretation exercises, not specifications for a stem, crank, saddle, rotor or frame. Do not apply them to hardware. If a relevant instruction is missing or contradictory, retain that uncertainty and obtain the applicable manufacturer clarification or qualified mechanical help.
Start with the exact joint, not the nearest number
Identify the component, generation, variant and receiving part, then locate the fastener or interface named in the applicable document. A crank fixing bolt and a separate adjustment cap can be on the same assembly while serving different purposes. A label beside one location does not automatically cover the other. Keep the drawing callout or section heading beside the reference so the next reader can find the same connection.
The size of a hex key identifies a tool interface; it is not the nominal thread size or a torque specification. Park Tool makes the head-size versus thread-size distinction in Basic Thread Concepts. Similar-looking fasteners do not become interchangeable instructions. For the reading record, use the actual part identifier and joint location rather than a shorthand such as the small bolt. A photograph may help identify a marking, but it does not establish hidden thread condition or the correct document revision.
Read the whole unit before converting a value
Torque combines force and distance. N·m denotes newton metres; N·mm denotes newton millimetres. The same torque expressed in N·mm has a numerical value one thousand times its value in N·m. They are not two spellings of the same scale. Preserve the original unit text even when you also write a converted value. A bare N is force, and an angle in degrees is another quantity again; neither can simply be relabelled N·m.
NIST SP811 lists rounded conversion factors of 0.1129848 N·m per lbf·in and 1.355818 N·m per lbf·ft. Fictional arithmetic: 4.00 N·m is approximately 35.40 lbf·in or 2.95 lbf·ft, and exactly 4000 N·mm as a unit rescaling. Conversely, 4.00 lbf·ft is approximately 5.42 N·m, not 4.00 N·m. One lbf·ft equals twelve lbf·in. These calculations check unit interpretation, not a real wrench setting, rounding permission or tool accuracy.
A range, a target and a maximum are different statements
Read the qualifying word together with the value. A document may give a permitted interval, a prescribed setting, an upper bound or a separate stage in a procedure. Do not delete that qualifier when transcribing the number. Writing only 6 beside a part loses both its unit and whether the source meant at most, within a range, or a particular instruction under named conditions.
For an entirely artificial example, source A states an interval from 4 to 6 units of N·m, while source B states a maximum of 5.5 N·m. The second statement provides no lower bound. It cannot establish that a value close to zero would secure the connection, and it does not tell you to choose 5.5. A midpoint is your arithmetic invention unless the actual applicable procedure says otherwise. Do not turn an upper limit into an installation target.
Resolve the receiving-part conditions without inventing agreement
If two fictional instructions genuinely apply to the same permitted connection, the numerical intersection of A’s 4–6 interval and B’s at-most-5.5 bound is 4–5.5 N·m. That is only a constraint exercise after the applicability assumption. It does not prove that the parts may be assembled, that either source is current, or that every value in the intersection is a safe operating choice. The real procedure and unresolved conditions remain separate.
A second fictional pair, 6–8 N·m and at most 5.5 N·m, has no common value. Do not average the documents, choose the lower maximum and continue, or interpret the empty intersection as a request for a stronger fastener. In its identified SI-0062A document, Shimano explicitly directs carbon receiving-surface torque questions to the frame or part manufacturer. That is a useful example of checking the receiver, not a transfer of that manual’s model-specific values or procedure to another assembly.
Torque indication is not a direct preload measurement
Park Tool distinguishes resistance to rotation from the tension generated in a fastener. Torque and preload are related, but the wrench does not directly measure the complete joint’s clamping force. The reference therefore cannot be detached from the specified connection and its condition. Reaching a number is not an independent inspection of threads, a clamp surface or the receiving part.
Keep three statements distinct in a discussion record: the source specifies something; a person reports carrying out a procedure; and the assembly has been physically checked by an appropriately competent person. Copying the first does not prove the second or third. A saved date or a neat report does not fill those gaps either. This guide has no sensor, wrench interface or physical inspection channel, so it cannot confirm any of those real-world events for you.
Preparation is part of the reference, not a universal recipe
Friction and thread preparation affect tightening, and manufacturer instructions can specify different preparation conditions. Park Tool’s thread discussion includes manufacturer exceptions rather than one treatment for every fastener. Retain the exact stated condition: do not silently change a dry, lubricated or otherwise specified connection into a different one while keeping the same number. Grease, an anti-seize compound, a threadlocking product and a surface assembly compound are not interchangeable labels.
This page does not tell you which substance to apply, where to apply it, how much to use or how to repair an old connection. Write the applicable instruction and any uncertainty beside the reference. If an old record merely says greased, that does not establish the product, surfaces, fastener condition or permission for a replacement part. Do not recreate missing preparation details by inference from a colour, a familiar brand or an internet torque chart.
Multiple fasteners and procedure stages stay separate
A pair or group of fasteners does not create a numerical total that you divide among them. Likewise, a later instruction in a multi-stage procedure does not erase an earlier one. The reading task is to preserve which instruction belongs to which location and stage, together with any specified sequence, gaps, supporting checks and conditions. It is not to simplify the source into one number for the whole component.
For example, a fictional note saying two locations both reference document Q is a source index, not a completed fastening record. It tells another person where to read. It does not say that the same setting applies to both, that the settings should be added, or that a visible gap should be removed. Leave those questions with the exact applicable procedure. Do not loosen parts merely to make a photograph resemble an abstract drawing or to finish a checklist in this app.
Check what the tool documentation actually covers
Before treating a displayed value as usable evidence, identify the tool and its applicable instructions. Retain the stated unit, supported measurement direction and range, configuration and any relevant inspection or calibration information. A visible scale is not a declaration that every point on it is suitable for your task. A reversible ratchet also does not, by itself, document measurement performance in both directions.
Display increments, a stated accuracy condition and the real condition of a particular tool are different records. This guide supplies no accuracy percentage, calibration interval, extension correction or substitute hand-force calculation. An attachment or changed configuration may need instructions of its own. If the applicable information cannot be established, record the tool question as unresolved instead of compensating with an invented setting. Choosing or checking the tool remains real mechanical work, not an action performed by reading this page.
Keep a source record that another person can follow
A useful technical note names the exact connection and parts; the document title, identifier and revision; the relevant page or section; the original wording, number and unit; the receiving-part conditions; and the preparation and tool questions that remain open. Keep any optional conversion alongside the original, labelled as arithmetic. Do not replace the source with a screenshot of a search result or a number copied from a different component generation.
A fictional entry might read: Joint A on SAMPLE component, document Q revision R, section S, original unit retained, receiver requirement unresolved, no installation reported. It is deliberately incomplete. That honest note is more useful than filling every space with guesses and presenting the result as ready. Keep an old reference as historical when the assembly changes; do not retrospectively rename it as evidence for the replacement hardware. Personal, contact or health information is unnecessary for this source-identification task.
Use the existing worksheet and workflow without bypassing their limits
The free blank worksheet has general procedure and reference spaces. Use your own supplementary technical paper notes for this torque record; there are no dedicated torque-specification fields in its fixed inventory. Reading the preview does not create a client record, download a file, print a document or send an inquiry. If you later make external copies, retain them within your own controlled workflow; closing this page cannot recall those copies.
The crank installation form’s Torque reference is entered text, not a torque calculator or a validation of the source. Its separate exact-component evidence, measurement and acknowledgment gates still apply. The guide link does not populate that field or check any box. Opening a reference is not completion of physical work. If a question about identity, applicability, preparation, conflicting limits or tool conditions remains unresolved, retain the question rather than recording a fictitious installation or assuming this guide has approved it.
Practical questions
Frequently asked questions
Is N·m the same as N·mm?
No. The numerical value in N·mm is 1000 times the value in N·m for the same torque. Preserve the original unit. Unit conversion alone does not choose a physical setting.
Are inch-pounds and foot-pounds interchangeable?
No. One lbf·ft equals 12 lbf·in. Read the complete unit rather than copying only the displayed number; a bare pound of force is not a torque unit.
Should I tighten to the maximum printed on a component?
A maximum is an upper bound, not automatically a target or a minimum holding requirement. Resolve the complete applicable joint and receiving-part instructions; this guide supplies no tightening setting.
Can I choose the lower of two conflicting torque instructions?
Not as a general assembly rule. First resolve whether both instructions apply to that exact permitted connection. An empty numerical intersection remains a conflict; even an overlap is not an installation approval.
Does a torque wrench prove the part is correctly installed?
No. Its indication is not a direct measurement of the whole joint’s preload, condition or compatibility. The actual procedure, applicable tool information and physical checks remain separate.
Will opening this guide complete the crank installation checks?
No. The fixed new-tab guide changes no field or acknowledgment and reports no physical work. Existing mechanical evidence, measurement and access gates remain required; do not claim a check you have not performed.