Yamaha RX 135 (4 & 5 Speed) Specifications, Review, Top Speed, Picture, Engine, Parts & History

Introduction

The Yamaha RX 135 occupies a special place in the story of lightweight performance motorcycles. Produced primarily between the mid-1980s and late 1990s (with some regional variations extending into the early 2000s), the RX 135 was the natural evolution of Yamaha’s earlier small-displacement two-stroke street machines. Offered in both 4-speed and later 5-speed variants, it combined modest engine capacity with spirited performance in a way that made it legendary—particularly in South Asia.

At a time when emissions regulations were less restrictive and two-stroke engines still dominated entry-level performance segments, the RX 135 delivered acceleration that embarrassed larger four-stroke rivals. It became popular not because of luxury or refinement, but because it was fast for its class, mechanically simple, and thrilling to ride.

Today, the RX 135 stands as a symbol of the golden era of small two-strokes—lightweight, raw, and mechanically honest. For collectors worldwide, it represents not just a motorcycle, but the end of an era before emissions controls gradually silenced the high-revving street two-stroke.

The successor of Yamaha RX 135 is Yamaha RX 100 & and the Competitors is Yamaha RX- K135.

Historical Background

To understand the RX 135, one must look at Yamaha Motor Company during the late 1970s and 1980s. Yamaha had already established a global reputation for building competitive two-stroke performance machines—both on the street and on the track. Models like the Yamaha RX 100 proved there was strong demand for lightweight, high-revving commuter-sport hybrids.

Why the RX 135 Was Launched

The RX 135 was introduced as a refinement and slight performance upgrade over the RX 100. Markets such as India, Southeast Asia, and parts of Africa demanded motorcycles that were:

• Affordable

• Reliable

• Fuel-efficient

• Quick off the line

Urban traffic conditions favored strong low- and mid-range torque rather than high top speed. Yamaha responded by slightly increasing displacement and refining port timing to improve rideability without sacrificing the trademark two-stroke snap.

Market Competition

The RX 135 faced competition from:

• Suzuki small two-stroke commuters

• Honda four-stroke commuter bikes

• Kawasaki-Badged regional small-displacement machines

While four-stroke rivals offered smoother operation and better fuel economy, they lacked the explosive acceleration of the Yamaha. In street culture, acceleration mattered more than brochure specifications.

Cultural and Racing Significance

Though not a factory race machine, the RX 135 became a favorite for grassroots racing, street drag competitions, and tuning communities. Its engine responded well to porting, expansion chambers, and carburetor upgrades. In some regions, it achieved cult status similar to larger performance icons like the Yamaha RD350—albeit in a more accessible package.

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Design & Engineering

Frame Type

The RX 135 used a steel tubular double-cradle frame. It was conventional, sturdy, and easy to repair—ideal for developing markets where durability and serviceability mattered more than advanced metallurgy.

The chassis prioritized stability and predictability over razor-sharp cornering. With narrow tires and simple suspension, it was agile at city speeds but less composed at sustained high speed.

Styling

Visually, the RX 135 retained the understated styling of its predecessor:

• Round headlamp

• Slim fuel tank with bold graphics

• Flat seat

• Chrome-finished exhaust (on earlier models)

It was neither futuristic nor flamboyant. Its appeal lay in its simplicity. In retrospect, that minimalism has aged well.

Build Quality

Build quality varied slightly by production batch and market. Japanese-engineered components were robust, but regional manufacturing tolerances sometimes introduced inconsistencies. Still, the mechanical design itself was inherently strong.

Unique Design Elements

• Compact two-stroke engine with excellent power-to-weight ratio

• Lightweight construction

• Mechanical simplicity allowing easy tuning

• Distinctive exhaust note that defined its character

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Engine & Performance (Realistic Analysis)

Engine Configuration

The RX 135 used a 132cc air-cooled, single-cylinder, two-stroke engine with reed valve induction (in most variants). It featured:

• Bore and stroke tuned for a balance of torque and rev capability

• Carbureted fuel delivery

• CDI ignition

The 4-speed variant offered punchy acceleration, while the 5-speed version improved flexibility and highway usability.

Power Delivery Characteristics

Power delivery was typical two-stroke:

• Soft below the powerband

• Strong mid-range surge

• Noticeable “hit” as revs climbed

The bike felt lively between 4,000 and 7,000 rpm. Acceleration was brisk for its displacement class, and its light weight amplified the sensation of speed.

Riding Experience

Riding the RX 135 today reminds you how engaging small motorcycles can be. Throttle response is immediate. The engine note is sharp and metallic. Gear shifts are mechanical and direct.

However, it demands involvement:

• Frequent gear changes

• Proper clutch control

• Attention to oil mixing (in non-autolube variants)

High-speed stability is adequate but not exceptional. Braking performance, especially with drum setups, reflects its era.

Mechanical Strengths

• Strong crankshaft assembly

• Responsive port design

• Excellent tuning potential

• Simple electrical system

Mechanical Weaknesses

• Piston and ring wear if poorly maintained

• Oil pump issues in neglected autolube systems

• Carburetor sensitivity to tuning

• Heat management under aggressive riding

Properly maintained, the engine is surprisingly durable.

Real-World Ownership Experience

Maintenance Difficulty

Mechanically straightforward. Any competent two-stroke mechanic can rebuild the engine. No complex electronics. No liquid cooling system.

Spare Parts Availability

In regions where it was widely sold, parts remain relatively accessible. Globally, sourcing original OEM parts is becoming harder. Aftermarket parts are common but vary in quality.

Collectors outside South Asia may rely on specialist exporters or enthusiast networks.

Reliability

When maintained correctly:

• Regular piston ring changes

• Clean carburetor

• Proper oiling

The RX 135 is reliable. Neglect, however, quickly leads to seizure or crank damage.

Common Mechanical Problems

• Worn piston rings

• Clutch plate wear

• Exhaust carbon buildup

• Weak drum brake performance

Fuel Efficiency

Historically, it returned reasonable mileage for a two-stroke—often 30–40 km/l under moderate riding. Aggressive riding reduces this significantly.

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Restoration Guide

Is It Easy to Restore?

Mechanically, yes. Cosmetically, increasingly challenging.

The simplicity of its construction means engine rebuilds are straightforward. However, finding:

• Original decals

• OEM exhausts

• Factory paint colors

is becoming difficult.

Parts Sourcing Tips

• Join regional enthusiast forums

• Seek old dealer inventory

• Consider importing from countries where stock remains

Avoid low-quality reproduction parts for engine internals.

Common Restoration Challenges

• Finding unmodified examples

• Repairing poorly done performance modifications

• Restoring original wiring harness integrity

Estimated Restoration Cost Range

Costs vary widely depending on region. A basic mechanical refresh is affordable. A full cosmetic restoration to near-factory condition can become significantly more expensive due to rare parts.

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Collector Value & Market Price (Global)

Current Auction Trends

The RX 135 is rising in value, especially well-preserved 5-speed models. While not yet at European classic levels, appreciation is steady.

Approximate Global Price Range

• Project bikes: modest prices

• Clean originals: mid-range collector pricing

• Fully restored, low-mileage examples: premium within niche markets

Prices vary greatly depending on country.

Investment Potential

Moderate but promising. As two-strokes disappear from roads, demand increases among enthusiasts who want authentic experiences.

Rarity Level

Not extremely rare, but original, unmodified examples are becoming scarce.

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Comparison with Similar Era Models

Compared with the Yamaha RX 100, the RX 135 offers slightly more torque and better cruising capability.

Against the Suzuki AX 100, it feels sharper and more performance-oriented.

Compared to small four-strokes from Honda, it is faster in acceleration but less refined and less fuel-efficient.

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Pros and Cons

Pros

• Excellent power-to-weight ratio

• Engaging two-stroke character

• Mechanical simplicity

• Strong enthusiast community

Cons

• Emissions restrictions limit usability in some countries

• Drum brakes are outdated

• Fuel consumption higher than four-strokes

• Increasing scarcity of original parts

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Who Should Buy This Motorcycle Today?

The RX 135 suits:

• Collectors of two-stroke motorcycles

• Enthusiasts who enjoy mechanical involvement

• Riders seeking nostalgic performance

• Restorers who value simplicity

It may not suit those wanting comfort, refinement, or long-distance touring capability.

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FAQs

1. Is the Yamaha RX 135 faster than the RX 100?
Slightly, particularly in mid-range torque and flexibility.

2. What is the difference between 4-speed and 5-speed versions?
The 5-speed offers better spacing and improved cruising efficiency.

3. Is the RX 135 reliable?
Yes, if properly maintained. Neglect leads to rapid wear.

4. Are parts still available globally?
Yes, but original OEM parts are increasingly rare outside its primary markets.

5. Is it a good investment motorcycle?
It has moderate appreciation potential, especially original examples.

6. Why did production stop?
Stricter emissions regulations made small two-stroke street bikes commercially unviable.

7. Can it be used as a daily rider today?
In regions without strict emissions laws, yes—but expect higher maintenance than modern bikes.

Yamaha RX 135 (4 & 5 Speed) Key Features

1. ENGINE Displacement 132cc
2. MAXIMUM POWER 14 BHP @ 7500 rpm (5 speed) & 12 BHP @ 7500 rpm (4 Speed)
3. MAXIMUM TORQUE 12.25 NM @ 7000 rpm (5 speed) & 10.0 NM @ 6500 rpm (4 Speed)
4. TOP SPEED 130 Kmph (5 Speed) & 120 Kmph (4 Speed)
5. MILEAGE PER LITER 25 - 35 Kmpl (4 & 5 Speed)

Yamaha RX 135 Photos

Yamaha RX 135 Infographics

Yamaha RX 135 5-Speed Technical Specs

Yamaha RX 135 4-Speed Technical Specs

Yamaha RX 135 Top Speed Video

Final Verdict

The Yamaha RX 135 is not a refined motorcycle. It does not offer advanced braking, modern emissions compliance, or sophisticated suspension. What it offers instead is authenticity.

It represents a period when small motorcycles were light, responsive, and mechanically transparent. Its engine demands respect. Its chassis rewards input. Its sound evokes an era that has largely disappeared.

For the vintage motorcycle enthusiast, the RX 135 is more than transport—it is a living example of accessible two-stroke performance. Balanced against its weaknesses, it remains one of the most engaging lightweight classics of its generation.