DC4 30x40.5x10.5mm NBR Double Spring Oil Seal For Motorcycle Shock Absorber
Model / SKU: VKEFOT-DC4-30-40.5-10.5-NBR
This aftermarket DC4 double spring oil seal 30x40.5x10.5mm in NBR, designed for motorcycle front fork and shock absorber sealing. For motorcycle repair and parts distributors; Lead Time: 7–15 days — RFQ with size, qty and destination.
Tags: 30x40.5x10.5mm, DC4 oil seal, double spring fork seal, motorcycle shock absorber, NBR fork oil seal
Product photos
Key specs: Inner diameter mm: 30 | Outer diameter mm: 40.5 | Height mm: 10.5 | Material: NBR | Material: NBR | Structure: DC4 double spring shock absorber oil seal | specifications: 30x40.5x10.5mm | Material: NBR
- Inner diameter mm: 30
- Outer diameter mm: 40.5
- Height mm: 10.5
- Material: NBR
- Material: NBR
- Structure: DC4 double spring shock absorber oil seal
- specifications: 30x40.5x10.5mm
- Material: NBR
- Structure: DC4 double spring shock absorber oil seal
- Size: 30x40.5x10.5mm
Technical summary
Product specifications. Refer to the approved drawing for dimensional tolerances and installation requirements.
| Spec | Value |
|---|---|
| Material | NBR |
| Structure | DC4 double spring shock absorber oil seal |
| Size | 30x40.5x10.5mm |
Pricing: request a quote (B2B / wholesale).
MOQ / commerce notes: MOQ: Depends on spec; typically 100–5,000 pcs | Lead Time: 7–15 days
Product details
This aftermarket DC4 double spring oil seal 30x40.5x10.5mm is a reciprocating motion seal built for motorcycle front fork and shock absorber suspension.
Buyers sourcing motorcycle suspension seals can submit RFQ with dimension, quantity and destination country. Lead Time: 7–15 days.
Features & Benefits
DC4 profile with dual garter springs maintains consistent lip pressure on reciprocating piston rod for reliable oil retention.
NBR rubber lip delivers good oil resistance and wear resistance under standard motorcycle fork operating conditions.
Dual lip design combines primary oil retention lip and secondary dust exclusion lip to protect internal suspension components.
Verify dimension and rod surface condition before installation, this seal is aftermarket replacement, not genuine OEM part.
- MOQ：Depends on spec; typically 100–5,000 pcs. Lead Time: 7–15 days. This SKU quantity confirmed on quotation.
Factory standard options, confirm on RFQ.
VKEFOT manufactures oil seals, O-rings and custom rubber seals in Xingtai and exports to Europe, North America, Middle East and Southeast Asia.
Material & Process
Sealing lip material: NBR nitrile rubber, typical working temperature -30°C to +120°C, short term peak up to +130°C, confirm compound grade with RFQ.
Rubber coated metal skeleton with dual garter springs, black finish.
Applications & Compatibility
Used for motorcycle front fork and shock absorber piston rod sealing, for motorcycle repair and maintenance.
Aftermarket replacement. Verify shaft diameter, housing bore and dimension before order.
Selection & Installation
Selection Tips
Confirm dimension 30x40.5x10.5mm, match material to your fork oil and working temperature.
Installation Steps
- Clean piston rod and fork housing completely, remove burrs, old seal residue and dirt.
- Protect sealing lips carefully to avoid scratches on rod surface during installation.
- Press the oil seal evenly, keep perpendicular to housing.
- Do not strike rubber body or hammer directly on seal surface.
- After assembly, test fork movement and inspect for oil leakage.
Packaging & Delivery
Standard neutral polybag + export carton. Normally 50–200 pcs per carton, adjustable.
- Lead Time：7–15 days for this standard spec.
Samples and small trial lots for stocked sizes; freight confirmed on RFQ.
Send an inquiry with size (ID×OD×height in mm), quantity, destination and duty for a firm lead time.
FAQ
I only have a competitor/OEM part number—can you cross-reference?
Yes. Send the reference PN, ID×OD×height in mm, and duty (media, temperature, pressure, speed). We match equivalents in the catalog; the Cross Reference page also searches by keyword. Final selection follows drawing and duty confirmation — do not order from a photo alone.
Do you support OEM/ODM, private packing and marking?
Yes — OEM/ODM from drawings or samples, plus agreed packing and marking. Share target-market compliance needs and annual volume; RFQ confirms process, tooling cost and cadence. VKEFOT is the export brand of the Xingtai factory, not a trading desk.
TC vs TB oil seal: which should I specify?
For a rotary shaft that needs a dust lip plus oil lip, start with TC (rubber-covered dual-lip is common); TB is typical when a semi-metal case needs a stiffer bore fit. Shaft diameter, housing, runout and dust still decide. Send ID×OD×height in mm and speed on the RFQ — not only a competitor photo.
NBR vs FKM oil seal for hot engine oil?
Continuous engine-oil duty near 120°C or fuel exposure should be reviewed as FKM; general mineral oil at moderate temperature and cost-sensitive repair jobs often stay NBR. Brown color is not proof of FKM. The quote names the grade and temperature limit — do not order by color.
Oil seal vs O-ring: when do I use which?
Use a metal-cased radial shaft (skeleton) oil seal for rotating shafts; use an O-ring for static glands or reciprocating grooves. An O-ring on a rotary shaft wears out quickly. VKEFOT makes both — state motion type (rotary/static/reciprocating) and ID×OD×section on the RFQ.
Cassette seal vs dual-lip TC for dusty construction equipment?
Ag gearboxes and construction travel shafts with mud and long service intervals should be reviewed as cassette/combined seals; many automotive hub repair jobs stay dual-lip TC. Cassette packs are thicker and need different bore and axial space. A job-site photo is not enough — send ID×OD×height.
Xingtai oil seal factory vs trading company — how do I tell?
VKEFOT is the export brand of Xingtai Hanchi Intelligent Technology Co., Ltd. Mixing, vulcanization and outgoing inspection run in Xingtai, then goods export to Europe, North America, the Middle East and Southeast Asia. A trading desk usually cannot change compound or cut tooling. For OEM drawings, ask who runs the process and QC — not only catalog price.
What is a skeleton / radial shaft oil seal?
A skeleton oil seal is a metal-cased radial shaft seal: the rubber lip rides the shaft and the case holds interference in the bore. Common styles include TC, TB and TA. Minimum spec is ID×OD×height in mm, compound and duty. VKEFOT catalogs automotive and industrial shaft seals; trust the product-page dimensions.
What do ID, OD and height mean on an oil seal RFQ?
ID is inside diameter (shaft), OD is outside diameter (bore), height is axial width, all in millimetres. Missing any one blocks a cross-reference. Example: 56×112×8/10 means 56 mm ID, 112 mm OD, 8/10 mm height. Put those three numbers and the compound on the RFQ.
Which oil seal for an automotive wheel hub or differential pinion?
Hub repair jobs often use dual-lip TC; differential pinion shafts often need a secondary lip or split height (e.g. 8/10 or 12/22 mm). Use measured or OEM dimensions — not a marketplace title. VKEFOT application pages cover drivetrains and hubs; send an OEM number or ID×OD×height on the RFQ.
How to select oil seals for ag gearbox and PTO shafts?
Ag gearboxes and PTO shafts see dust and shock — prefer a dust lip or cassette, with NBR or FKM matched to gear oil and temperature. Do not force a passenger-car hub seal onto a PTO shaft. Send shaft, bore, height and whether mud/water is present, then RFQ.
What matters for pump, valve and compressor shaft seals?
Match media (oil, water, gas) and temperature first, then lip style and compound; do not default to cheap NBR for high speed or dry running. Put shaft runout and eccentricity on the RFQ. VKEFOT application cases include pumps, valves and compressors — still use measured sizes.
Does a brown oil seal mean it is FKM?
No. Brown NBR is common; color is not proof of FKM. For heat or fuel duty, write temperature and media on the RFQ so the factory names the grade. Ordering by color is a frequent cause of early leak.
Can you quote an oil seal from a photo only?
Not as a firm quote. We need at least ID×OD×height in mm, ideally compound and speed. A photo can show lip count and case style; it does not replace dimensions. Incomplete RFQs get a request for those three numbers before price.
If a new oil seal leaks quickly, is it always a bad seal?
Not always. Rough shaft finish, runout, cocked installation or the wrong compound also leak early. Check size and media/temperature match before blaming the part, then inspect the journal. Note time-to-fail (e.g. 50 hours) on the RFQ so we diagnose — do not just buy a cheaper seal.
What is needed for private-label OEM packing of oil seals?
Private packing and marking need annual volume, target-market compliance and artwork; tooling cost and cadence are confirmed on the RFQ — not a one-line “please OEM”. VKEFOT runs OEM/ODM after drawings or samples are complete.
Who is VKEFOT and how does it relate to Xingtai Hanchi?
VKEFOT manufactures oil seals, O-rings and custom rubber seals in Xingtai and exports to Europe, North America, Middle East and Southeast Asia. The manufacturer is Xingtai Hanchi Intelligent Technology Co., Ltd. Use this wording on quotes and certificates — do not invent alternate spellings of the brand.
What is DC4 30x40.5x10.5mm double spring oil seal used for?
DC4 30x40.5x10.5mm NBR double spring oil seal is used for motorcycle front fork and shock absorber piston rod sealing, to retain fork oil and block dust and water ingress.
What is DC4 type double spring shock absorber oil seal?
DC4 oil seal is a reciprocating motion seal with dual garter springs and double lips, designed for motorcycle suspension to maintain stable lip pressure on moving piston rod.
What material is this DC4 motorcycle fork oil seal?
Made of NBR nitrile rubber, good compatibility with conventional motorcycle fork oil and shock absorber fluid.