True to its trail-bike lineage, the Yamaha DT250 brings with it a promise of safe riding and adventure. One of the leading dual-sport machines in its heyday, the 250-cc wheeler was an answered prayer for DT 125 enthusiasts. It was sleek, nostalgic, and simple – qualities sought after even in today’s market.
The Yamaha DT250 was an enduro-style dual-sport bike produced by Yamaha from 1971 to 1982. This motorcycle featured unobtrusive styling, an 85-mph top speed, and a YZ-adapted mono-cross rear suspension. It handled smoothly on the road as it did on trails.
Service limitations aside, the Yamaha DT250 is a top choice among frugal riders and enthusiasts enamored by retro-styled bikes. Learn more about the DT250, and let this guide enlighten you on its specs and endearing qualities.
About Yamaha DT250
Like its smaller-displacement sibling, the Yamaha DT250 is a descendant of the 1968 DT-1 Enduro – the trailblazer that kicked off the off-road-friendly two-wheeler niche for Yamaha.
The DT250 was the 9th largest motorcycle class in the DT series and launched three years earlier than its 125-cc namesake. It launched at perfect timing, intended to coincide with the shift of consumer interest from road-legal to off-road-worthy vehicles.
Expectedly, the DT 250 is not without competition, and it is in this aspect that many enthusiasts found Yamaha lacking. It would have been an opportune time to go all out on vehicle enhancements and reap back in profits spent on refinements.
However, Yamaha appeared to have perceived the situation differently. Had it done the same degree of enhancement on the DT250 as it did on the RD400, the firm would have gone against the very essence of the DT series. While it is true that dual-purpose machines should be functionally competitive, they should also be within the buying means of the general public.
In hindsight, the Yamaha DT250 trod the path meant for it. After all, purpose-built wheelers ordinarily progress slowly but surely. To support this point, Yamaha did introduce some notable improvements on the motorcycle, namely – the MX rear suspension, reed-valve torque induction, electronic CDI system, and automatic oil injection. While not flashy, these upgrades improved the overall performance and appeal of the street trail bike.
Yamaha DT 250 Specs & Features
An air-cooled, 2-stroke single-cylinder engine with torque induction brings the Yamaha DT250 to life. It has a bore-stroke ratio of 70 x 64 mm (2.76 × 2.52 inches). Engine displacement is 246 cm³ (15.01 in³), while the compression ratio is 6.7:1. A 28-mm Mikuni carburetor handles the air-fuel mixture. A plunger-type oil pump and oiled foam rubber air filter complete the bike’s powerplant assembly.
The dirt bike’s engine configuration lends to a top speed rating of 68 mph (109 km/h), maximum torque of 17.5 Nm (1.78 kgf-m, 12.95 ft-lb) @ 6,500 RPM, and 15.69 hp (11.7 kW) @ 5,400 RPM horsepower. Pre-1978 Yamaha DT250 models reportedly had a slightly higher horsepower output at 20 hp (14.91 kW) @ 6,500 RPM and a 26% difference in top speed at 85 mph (137 km/h) when compared to later-year versions.
(1977 Yamaha DT250F advertised figures: 23 bhp @ 6,000 RPM; 27 Nm/2.8 kgf-m, 20.25 ft-lb @ 5,000 RPM)
Fuel & Lubrication
Tank capacity is 9 liters (2.38 US gal) of unleaded gasoline with a minimum PON 87/RON 91 rating. Fuel travels via a membrane and lends to an impressive fuel economy of 94 MPG (2.50 L/100 km). For top performance, the bike requires fuel variants containing < 5% MTBE (Methyl Tertiary Butyl Ether), < 10% ethanol, or < 5% methanol. However, veterans advise veering away from fuel with methanol due to its formaldehyde content.
The engine oil capacity is 1,200 ± 50 cc (dry) or 1,100 ± 50 (oil change) of Yamalube SAE 10W-40 2-stroke oil or its equivalent. For compatible variants, the minimum API grade required is SJ and should meet JASO T903 MA standards. You may opt for other manufacturer-recommended viscosity grades, depending on ambient temperature. When uncertain, always refer to the service manual for specifics on oil requirements.
A manual, 5-speed constant mesh drum-shifter system and a wet multiple-disc clutch assembly deliver power to the ground. A Daido DK520DS roller chain (with 104 links including joint) handles wheel spin. The dirt bike’s wide-ratio transmission makes it comparable to counterparts like the Harley-Davidson SX250, Team Green’s KE250B, and the Honda XL250 – to name a few. For improved acceleration, you may adjust the front sprocket 1-2 teeth lower.
For reference, the stock gear ratios are below:
|Primary Reduction Ratio||2.826 (65/23)|
|Secondary Reduction Ratio||3.357 (47/14)|
|Transmission Gear Ratio (1st)||2.538 (33/13)|
|Transmission Gear Ratio (2nd)||1.789 (34/19)|
|Transmission Gear Ratio (3rd)||1.300 (26/20)|
|Transmission Gear Ratio (4th)||1.000 (23/23)|
|Transmission Gear Ratio (5th)||0.769 (20/26)|
A Contact Breaker Point ignition system and a primary kick-starter wake up the DT250. Compared to an electronic ignition system (which is commonplace for DT250 dirt bikes), the ECU shuts the former’s primary circuit on or off.
Likewise, it runs on lower voltage and distributes the same to the ignition coil and wiring systems. It took almost six years for Yamaha to change the breaker-point ignition into a CDI system.
Including the 1978 Yamaha DT250, all pre-1980 models require an NGK B8ES spark plug with a gap of 0.7 – 0.8 mm (0.028 – 0.031 inches).
As for battery requirement, the models split into two groups. 1974 to 1975 Yamaha DT250s had 4Ah/(10 HR) 6N4B-2A-3 battery formats (view on Amazon), while ’76 to ’79 DT 250s had 6Ah/(10 HR) 6N6-3B-1 batteries.
They differ in both amperage and dimensions and are non-interchangeable. The 6N4B-2A-3 format measures 102 x 48 x 96 mm (4.00 x 1.88 x 3.75 inches), while the 6N4B-2A-3 format measures 99 x 57 x 111 mm (3.88 x 2.25 x 4 .38 inches).
Tires & Brakes
E-type aluminum wheels are equipped with Dunlop® 3.00 x 21 4PR front tires and 4.00 x 18 4PR rear tires. This tire-and-wheel assembly mate to 160-/150-mm expanding drum brakes that provide the DT250 stopping power.
In the event of damage or wear, swap the stock rubber out for Shinko 700 Dual Sport Front Tires (view on Amazon). For serious mudding or more aggressive tracks, replace the rear tires with Dunlop D605 Dual Sport Tires (view on Amazon).
Recommended tire pressure is dependent on speed and rider weight. For normal riding, cold tire pressure should be 127.5 kPa (1.3 kgf/cm², 18.5 psi – front) and 147 kPa (1.5 kgf/cm², 21 psi – back). For high-speed riding or with a passenger, tire pressure should be 147 kPa (1.5 kgf/cm², 21 psi) and 176.5 kPa (1.8 kgf/cm², 25.6 psi) at the front and rear, respectively.
The long-travel suspension consists of a front oil-damped telescopic fork with a forward-mounted axle. At the back, you will find a DeCarbon-type, mono-cross swingarm taken from the YZ lineup. Each setup offers 195 mm (7.6 inches) and 140 mm (5.5 inches) of wheel travel, respectively.
A nitrogen-charged mono-shock with softer spring rates supplements the rear cantilever. The entire suspension system lends to the DT250’s superb handling, decent cornering, and improved performance on the rough.
Dimensions & Capacities
Overall vehicle dimensions are 2,185 x 870 x 1,165 mm (86 x 34.3 x 45.9 inches – L x W x H) – exactly alike its bigger sibling, the Yamaha DT400D. Later-year releases also retained the same measurements, with slight improvements in wheelbase (from 55.7 to 55.9 inches). The saddle sits at 856 mm (33.7 inches) high, while the ground clearance lacks at 255 mm (10 inches). Minimum clearance later improved to 277 mm (10.9 inches) for succeeding models.
The bike’s dry and wet mass gradually increased since its first production model. From 129 Kg (284 lbs.) in 1974, the DT250 went on to add another six (6) kilograms to its curb weight. Redesigning the fuel tank and taking a bit away from the fuel capacity helped trim the wet weight down for post-1977 models to 131 Kg (289 lbs.).
An aluminum skid plate protects the crankcase from scratches and gnarls. Turn signals are tucked in at the front while protected by rubber mounts at the back. Serrated, folding footpegs are 13 inches high, supporting a more comfortable but aggressive riding position. Round headlights wrap up the DT250’s classic look, which is highly characteristic of its era.
As already established, among the Yamaha DT 250’s strongest charms is its nostalgic, vintage styling. It prides itself on its ’70s look and dual pieces like brake levers, instrumentation, and duplex frame. However, it received very little to almost no cosmetic upgrades throughout its run. Redesign of its fuel tank and seat comprise most of the bike’s aesthetic enhancements.
Despite this shortcoming, the DT250 is well-appreciated for its practicality and even weight distribution. This works in the two-wheeler’s favor since it is a bit heavy for a 250-class dirt bike. Thankfully, there are tons of aftermarket options out there that would enable any owner to shed some weight off the trail bike and prevent it from looking too dated.
Yamaha DT250 Price
The Yamaha DT250 list price went up by a little over $500 from its debut to its final-year production model. While this seems like a small mark-up by today’s standards, this 250-cc wheeler was one of the pricier options during its time.
Interestingly, enthusiasts who bought their share of the iconic bike seem to be reaping the rewards of a near-mint, well-maintained unit. Nowadays, the DT250 sells within the range of $425 to $8,545 – just based on Nada Guides’ data.
|Model Year & Trim||List Price||Retail/Trade-in|
|1971 DT1E Enduro 250||N/A||$730 – $7,275|
|1971 DT1MX Motocross 250||$730 – $8,545|
|1972 DT2E Enduro 250||$730 – $4,745|
|1972 DT2MX Motocross 250||$730 – $7,275|
|1973 DT3 Trail and Enduro 250||$495 – $3,510|
|1974 Yamaha DT250A||$949||$425 – $3,195|
|1975 Yamaha DT250B||$425 – $3,195|
|1976 DT250C||$1,087||$425 – $3,195|
|1977 DT250D||$1,089||$425 – $3,195|
|1978 Yamaha DT250E||$1,198||$425 – $3,195|
|1979 DT250F||$1,474||$730 – $2,655|
Yamaha DT250 Pros and Cons
- Charming, vintage styling never fails to captivate consumers and avid followers.
- A contoured saddle seat makes room for two riders while providing riding comfort.
- The rear swingarm lends to the bike’s impressive handling, especially off-road.
- Mechanical components are straightforward and almost maintenance-free if well taken care of.
- Repair and replacement parts are readily available in the market due to the lineup’s huge aftermarket support.
- Some riders find that the bike does not inspire confidence when riding, especially on more technical terrain.
- The bike’s vintage looks are reflective of its equally vintage performance.
- Steering head bearings are a sure-fire pain point for this wheeler, even when brand-new.
- In stock form, the bike does not come with a rear luggage rack. This is not that big of a hassle, although enthusiasts wished it had the accessory from the get-go.
- Up until 1982, the wiring and electrical components of the bike were 6V. If you want to upgrade headlamps, improve light distribution, and make your bike street-legal, purchase a 12V converter kit.
- There is a slight delay in engagement when squeezing the front brake lever. Luckily, veterans have discovered that an ’81 YZ250 backing plate with two levers pressing the brake shoes from two separate locations resolves the problem. Naturally, it will be much better to switch to a front disc brake.
Unlike current dual-sport machines, the DT250 is designed for use 70% off-road and 30% on-road, which explains its seemingly non-existent stopping power on pavement, plus other service limitations. Its handling and suspension geometry is better suited for dirt roads.
Although it was founded in 1887, Yamaha Motor Company Limited did not begin its journey in the automotive world until 1955 – when it parted ways with its parent company shortly after World War II. From manufacturing musical instruments, Yamaha’s founder would have never guessed that it would be a gamechanger in the motorcycling and ATV markets. Fast forward to today, Yamaha is a well-renowned global leader unrivaled in its water vehicle sales and innovations in multiple industries.
Conclusion – Yamaha DT250 Review
The Yamaha DT250 may have only received a few styling upgrades during its period. But what it lacked in aesthetics, it made up for in the things that mattered – among them the ’72 reed-valve torque induction, the ’77 cantilever rear suspension, and the shift to a CDI system in ’79.
By no means is this classic faultless. But like most pioneering vehicles, it gives a glimpse of the near-perfectibility of dual-purpose bikes. The DT250 continues to challenge the riding prowess and the mechanical genius of recreational riders and enthusiasts alike. And if you are up for this kind of experience, the Yamaha DT250 is, undoubtedly, your perfect ride.