Royal Enfield Flanged Hex Bolt M6×27 – Fuel Tank, Engine Cover & Chassis Applications – 591577/D

Genuine Royal Enfield 591577/D is the current service revision of the widely used FLANGED HEX BOLT M6X1X27 family. It appears across multiple Royal Enfield assemblies including fuel tanks, engine covers, electrical brackets, seats and chassis components.

Part Identification

Short Hook

Replace missing, corroded or incorrect factory hardware with genuine Royal Enfield 591577/D, the current service bolt used across fuel-tank, engine-cover and chassis assemblies on several Royal Enfield generations.

Detailed Product Description

Royal Enfield 591577/D is a genuine flanged hex bolt used in many different motorcycle assemblies. Earlier factory part numbers 591577/A and 591577/C are both explicitly shown in current genuine-parts data as replaced by 591577/D.

Most Royal Enfield EPCs, current European microfiches and the Continental GT 650 technical manual describe 591577/D as FLANGED HEX BOLT M6X1X27. One current genuine-parts price database instead describes the same /D SKU as M6X25, grade 8.8, ZnFe white.

Because Royal Enfield's current databases are inconsistent on the nominal length wording, order this bolt primarily by the exact part number 591577/D and the motorcycle's EPC position rather than substituting a generic M6 bolt purely by measured length.

What This Product Is

• Genuine Royal Enfield OEM flanged hex bolt.
• M6 × 1.0 thread family.
• Current service revision 591577/D.
• Used in multiple model and assembly locations.
• Sold individually.

What This Product Is Not

• Not a socket-head cap screw.
• Not 575900/B M6×40 engine-cover bolt.
• Not 575901/A M6×50 engine-cover bolt.
• Not H6902012 M6×30 bolt.
• Not 591578-series longer flanged bolt.
• Not a universal substitute for every M6 Royal Enfield fastener.

Key Features

• Genuine Royal Enfield OEM hardware.
• Integral flange under the hex head.
• Current /D service revision.
• Replaces documented earlier /A and /C revisions.
• Used widely across genuine Royal Enfield parts books.
• Exact part-number identification prevents wrong-length / wrong-head-style substitutions.

Buyer Search Names / Internal Search Keywords

591577/D, 591577D, 591577, 591577/A, 591577/C, Royal Enfield M6 bolt, M6x27 flanged hex bolt, fuel tank bolt, tank mounting bolt, engine cover flange bolt, Royal Enfield flange bolt, Classic 500 tank bolt, GT535 tank bolt, Himalayan 411 tank bolt, Interceptor 650 tank bolt, GT650 bolt.

Confirmed Compatibility / Applications

Important: Application Quantity Varies

This bolt is reused in many positions, so the required quantity is not universal.

• Many fuel-tank applications: Qty 2.
• Some GT535 / Himalayan tank variants: Qty 1 or 2 depending on exact assembly.
• GT650 engine-cover application: Qty 1 in the specific listed position.
• Other electrical / chassis applications: quantity varies.

Shopify Quantity 1 = One Individual Bolt.

Fitment Not Confirmed / Check Before Ordering

Part Number / Supersession Notes

Dimension Wording Caution

Most current model catalogues and microfiches call 591577/D = M6×1×27.

However, one current genuine-parts price database describes 591577/D as:

FLANGED HEX BOLT - M6X25 8.8 ZNFE WHITE

This listing therefore prioritizes exact part number 591577/D over generic dimensional substitution. If a customer is buying solely by dimensions rather than by OEM part number, compare the genuine physical bolt or VIN-specific EPC before dispatch.

Similar Parts Comparison

When Should This Be Replaced?

• Hex head is rounded.
• Threads are stripped or damaged.
• Bolt is bent.
• Flange is damaged.
• Bolt is heavily corroded.
• Incorrect generic hardware was previously installed.
• Factory bolt is missing after tank / cover / bracket removal.

Recommended Related Parts to Check

• 594538 – Fuel-tank washer where applicable.
• 594264 – Rear tank damper where applicable.
• 594268 – Front tank damper where applicable.
• 585659 – Fuel-tank / oil-cooler bush where applicable.
• Correct nuts, washers and sleeves for the specific mounting position.

What’s in the Box

1 × Genuine Royal Enfield 591577/D Flanged Hex Bolt

Washers, nuts, tank bushes, dampers and other mounting hardware are not included unless explicitly stated.

Installation Notes

1. Confirm the exact EPC position specifies 591577-series.
2. Inspect the female thread / captive nut before installation.
3. Compare the removed bolt and mounting stack.
4. Do not substitute a generic M6 bolt solely because the thread fits.
5. Tighten to the workshop-manual torque for the specific assembly.
6. Do not overtighten fuel-tank mounts or rubber-bushed assemblies.

Return-Prevention Note / Before You Buy

1. Match exact SKU 591577/D.
2. Confirm the exact motorcycle assembly uses 591577.
3. Check required quantity.
4. Do not confuse with 591578 longer flange bolt.
5. Do not confuse with 575900/B, 575901/A or other M6 engine-cover bolts.
6. If buying by measurement only, verify the physical bolt because Royal Enfield databases contain conflicting M6×25 / M6×27 wording for /D.

Correctly supplied fasteners are not returnable or exchangeable because of incorrect length selection, wrong assembly, model mismatch, installation attempt, mechanic recommendation or change of mind. Eligible wrong-item or damaged-item claims require applicable proof and complete unboxing evidence under store policy.

FAQs

What is Royal Enfield 591577/D?
It is a genuine flanged M6 hex bolt used across multiple Royal Enfield assemblies.

What did 591577/D replace?
Current genuine-parts data explicitly shows both 591577/A and 591577/C replaced by 591577/D.

What size is it?
Most model EPCs and current microfiches identify it as M6×1×27. One current genuine-parts database labels /D as M6×25 grade 8.8 ZnFe white, so exact OEM part-number matching is safest.

Does it fit Classic 500?
Yes, in several fuel-tank, seat and electrical positions where 591577 is specified.

Does it fit Continental GT 535?
Yes. The fuel-tank EPC lists base 591577.

Does it fit Himalayan 411?
Yes. Base 591577 appears in Himalayan fuel-tank and rear-suspension catalogues.

Does it fit Interceptor 650?
Yes in documented fuel-tank applications.

Does it fit Continental GT 650?
Yes. The GT650 technical manual directly lists 591577/D in fuel-tank and engine-cover sections.

Is it the same as 575900/B?
No. 575900/B is an M6×40 socket-head engine-cover bolt.

Does quantity 1 mean a set?
No. Quantity 1 means one bolt.

SEO Tags

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Image Filename Suggestions

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Image Alt Text

Genuine Royal Enfield 591577/D flanged M6 hex bolt used in fuel-tank, engine-cover and chassis assemblies

Google Shopping Notes

Competitor Gap Analysis

Most listings simply show “FLANGED HEX BOLT M6X1X27.” This listing improves buyer accuracy by documenting the /A and /C to /D replacement chain, showing multiple genuine applications, warning that quantity varies by assembly, separating 591577/D from longer M6 engine-cover bolts, and transparently addressing the conflicting M6×25 versus M6×27 wording found in current Royal Enfield genuine-parts databases.