Rolon BSOR TB09 350 Chain Sprocket Kit for Royal Enfield Thunderbird 350 / Thunderbird X / Classic 350 Gunmetal Grey / Signals 350 (16T–38T Solid Bush O-Ring Chain)

If your Thunderbird or Classic 350 has started feeling jerky, noisy or inconsistent under acceleration, it’s usually the chain and sprocket set asking for retirement. The Rolon BSOR TB09 350 Chain Sprocket Kit is a direct-fit, OE-spec replacement engineered specifically for Royal Enfield’s 350cc rear-disc UCE models – Thunderbird 350, Thunderbird X, Classic 350 Gunmetal Grey and Signals 350.

Using Rolon’s solid-bush O-ring sealed chain with 16T front / 38T rear sprocket combo, this kit is designed to deliver smoother power transfer, reduced chain slap and noticeably quieter running compared to worn stock kits. The sprockets are induction-hardened, high-carbon steel, built to exceed OEM standards and handle loaded touring, city abuse and Indian monsoon conditions with ease.

Unlike generic local kits, TB09 350 is based on Rolon’s official fitment for Thunderbird 350 / Classic 350 Gunmetal Grey / Signals 350 with rear disc and ABS.

Buying from Under The Hood means you get 100% genuine Rolon stock, fresh inventory, careful packaging and guidance from a workshop that actually installs these kits on customer bikes every week. Pair it with a good chain cleaner and lube from our store and you’ll get a long-lasting, low-maintenance drivetrain that feels tight, smooth and ready for long rides.

Key Features 

• Genuine Rolon BSOR TB09 350CC kit – direct OE-spec replacement for selected 350cc Royal Enfield rear-disc models.

• Solid-bush O-ring sealed chain for better lubrication retention, longer life and lower maintenance than open chains.

• Optimised 16T front / 38T rear sprocket combo for stock-like gearing with smoother acceleration and reduced jerks.

• Approx. 102-link chain as per Rolon kit catalogue, designed to match OEM wheelbase and adjuster range.

• Induction-hardened, high-carbon steel sprockets for excellent wear resistance and consistent tooth profile.

• Lower NVH – reduced chain slap and mechanical noise when properly tensioned and lubricated.

• All-weather performance – surface treatments and sealing help resist rust, dust and mud on Indian roads.

• Direct fitment on OE hub pattern – no modifications required on compatible rear-disc models.

• Ideal for touring + city usage – handles luggage, pillion weight and daily stop-go traffic.

• Under The Hood advantage – verified fitment, expert support from a real Royal Enfield-focused workshop, and fast, secure shipping across India.

Compatibility Table

*Year range based on Rolon catalog and multi-dealer listings; always confirm rear hub disc setup (16T front / 38T rear, 6-hole pattern) before ordering.

Not compatible with:

• Classic 350 rear drum models

• Bullet 350 / Electra drum-brake variants

• J-Series Classic 350 Reborn or newer 350 platforms

Variants

This listing is for the standard steel Solid Bush O-Ring TB09 350 kit.

If a customer wants a gold/brass finish look, they should instead choose a Rolon brass kit (e.g., BSORTB09) which uses similar 16T–38T / 102L specs but with brass-plated chain plates for aesthetics and extra rust protection. (List separately on underthehood.co.in as a different product.)

What’s in the Box

• 1 × Rolon front sprocket – 16T (OE-spec spline & PCD)

• 1 × Rolon rear sprocket – 38T (flower-window pattern for rear-disc hub)

• 1 × Rolon Solid Bush O-Ring drive chain (approx. 102 links, pre-lubricated)

• Rolon branded packaging with basic installation / care instructions (as supplied by manufacturer).

Installation & Maintenance Notes

• Always compare the old sprockets (tooth count, hub pattern) and chain length before final installation.

• Follow Royal Enfield’s recommended chain slack (approx. 20–30 mm free play) measured midway between sprockets with the bike on main stand.

• Tighten axle and adjuster nuts to OEM torque settings; re-check slack after a short test ride.

• Use a proper chain cleaner (or kerosene + mild brush) and re-lube every 500–700 km or sooner in rain/off-road conditions, as recommended in Rolon’s kit catalog.

• Avoid over-tightening the chain – a too-tight chain will wear sprockets, stretch links and stress gearbox output bearings.

• Inspect sprocket teeth and chain regularly; replace as a set to avoid premature wear.

FAQs 

Q1. Will this Rolon BSOR TB09 350 kit fit my Thunderbird 350 rear-disc model?
Yes. BSOR TB09 350 is specified by Rolon for Thunderbird 350 rear-disc/ABS models and widely sold by multiple dealers as the correct kit for these bikes. Just confirm your bike has a rear disc brake and 16T/38T sprocket combo before ordering.

Q2. Is this better than the stock Royal Enfield chain sprocket kit?
Performance is comparable or better. Rolon is an OE supplier and this kit uses a solid-bush O-ring chain and hardened sprockets, designed to match or exceed OEM strength and service life when maintained properly. Many riders report smoother power delivery and less noise after replacing a worn stock kit with BSOR TB09.

Q3. Will this kit fit Classic 350 Reborn (J-Series) or Bullet 350 BS6?
No. This kit is for older 346cc UCE rear-disc models only (Thunderbird 350 / Thunderbird X 350 / Classic 350 Gunmetal Grey / Signals 350). It does not fit J-Series Classic Reborn, new Bullet 350 J-platform or earlier drum-brake Bullets.

Q4. Is this original Rolon or a local duplicate?
Under The Hood sources directly from authorised Rolon distributors and lists the official KIT BSOR TB09 350CC code in the title and description. You’ll receive sealed Rolon packaging with correct branding and part markings – not loose, unbranded spares.

Q5. Does this chain sprocket kit affect mileage or top speed?
Since the kit retains the stock 16T–38T gearing, your bike’s gearing, top speed and cruising RPM remain the same. You may experience slightly better pickup and smoother cruising simply because a fresh, correctly-tensioned chain & sprocket set wastes less power compared to a worn, stretched setup.