Yamaha TTR 125 in white text on gray background with image of Yamaha TTR 125 dirt bike

James Stewart

Yamaha TTR 125 Complete Guide


How many times have you searched the internet for a simple answer to a question you have about a Yamaha TTR 125 only to find a page with a wall of text and thousands of words making it difficult to find the simple answer you’re looking for?

Our goal is to not only answer any question you’re looking for about the Yamaha TTR 125, but to give you the answer quickly and make it simple to find. We provide the most common and important information upfront, with more detailed information following that, and wrap up the article with frequently asked questions.

You can click the topic you’re looking for in the table of contents below to go directly there, or simply scroll to the sections below. This allows you to quickly find the information you want.

Let’s get into the Yamaha TTR 125.

Most Important & Common Want-to-Know Information about the Yamaha TTR 125

TTR 125 Horsepower

As dirt bike riders, we have to know how fast our bikes go and how much power they have. Even though the Yamaha TTR 125 is a trail bike, we’re still curious.

The TTR 125 horsepower is about 7 hp. (this is about the same horsepower the Yamaha TTR 110 makes.)

How does this horsepower translate to speed? Here you can find our full article on the TTR 125 top speed.

TTR 125 Carburetor or Fuel Injection

Although some brands are starting to bring fuel injection to their trail bikes, like Honda’s CRF110, Yamaha has not started to do that yet (we hope they will soon!). Therefore, the TTR 125 is not fuel injected and it has a carburetor.

If you are having trouble with your TTR 125 running properly, be sure to read our lean bog vs rich bog guide.

Electric Start or Kick

Similar to fuel injection, with technology in dirt bikes improving over the years, most brands are moving a lot of their models over to electric start (if they haven’t already). Suzuki hasn’t yet, even on their motocross bikes, but that’s another story…

Since 2003, the TTR 125 has had electric start. Unlike Yamaha’s YZ250F and YZ450F, it does still have a kicker installed so you can kickstart it if needed.

TTR 125 Oil

Yamaha recommends the TTR 125 oil to be 10W-40. The TTR 125 oil capacity is 1.06 quarts.

Wheels and Tires

The Yamaha TTR 125 (LE model) comes stock with a 19-inch front wheel and a 16-inch rear wheel. The front tire dimensions are 70/100-19 and the rear tire dimensions are 90/100-16. The bike comes stock with IRC brand tires (IX05H model).

TTR 125 Weight

A TTR 125 weight is about 198 pounds wet.


In the front, the Yamaha TTR 125 comes stock with 31mm telescopic forks that have 7.1 inches of travel and allow you to adjust the preload. The rear shock has 6.6 inches of travel and allows you to adjust compression and rebound.


The TTR 125 comes stock with a 110mm drum brake in the rear and a 220mm hydraulic disc brake in the front.

Yamaha TTR 125 Overview

The Yamaha TTR 125 isn’t considered a speed demon, it’s a trail bike, not a motocross bike, but it’s a great, affordable and reliable dirt bike. Beginners and older children won’t be scared by the bike having too much power and it’ll be easy to learn on.

Adults and more experienced riders may use this dirt bike as a slightly larger version of a pit bike, as it’s a bit bigger than a standard 110cc pit bike. It can also be a great bike for you to ride around on while your younger kids ride their 50s (or any dirt bike).

If you’re into the TTR 125, you’re probably a Yamaha fan, like me, but a comparison that is often made is the TTR125 vs KLX140. Check it out.

Yamaha TTR 125 dirt bike

TTR 125 Specs

Above in this article, we touched on the most important and common want-to-know information about the Yamaha TTR 125. In this section here, we’ll provide all of the technical specs about this dirt bike.

Engine Specs

  • Displacement: 124cc (rounded up to 125cc)
  • Bore x Stroke: 54mm x 54mm
  • Compression Ratio: 10:1
  • Fuel Delivery: Mikuni VM20 Carburetor
  • Ignition: CDI
  • Transmission: manual 5-speed, multi-plate wet clutch
  • Drive: Chain
  • Engine Type: 4-stroke
  • Cooling System: Air cooled
  • Valve Train: SOHC
  • Number of Cylinders: Single cylinder

Chassis Specs

  • Front Suspension: 31mm telescopic forks with adjustment preload (7.1 inches of travel)
  • Rear Suspension: single shock with adjustable rebound and compression (6.6 inches of travel)
  • Front Brakes: 220mm hydraulic disc
  • Rear Brakes: 110m drum
  • Front Tires: 70/100-19
  • Rear Tires: 90/100-16


  • Length: 74.2 inches
  • Width: 31.3 inches
  • Height: 42.7 inches
  • TTR 125 Seat Height: 31.7 inches
  • TTR 125 Wheelbase: 50 inches
  • Rake: 28.5 degrees
  • Trail: 4.2 inches
  • TTR 125 Ground Clearance: 11.6 inches
  • Fuel Capacity: 1.6 gallons
  • Fuel Reserve Amount: 0.21 gallons
  • TTR 125 weight: 198lbs

Different Yamaha TTR 125 Models

Over the years, Yamaha has made a few different TTR 125 models. It has the baseline model, the TTR 125, then there’s the TTR 125E, TTR 125L, and the one we’ve discussed here, the Yamaha TTR 125LE. Here are the differences in the models:

Wheels & Tires:Front: 17″
Rear: 14″
Front: 17″
Rear: 14″
Front: 19″
Rear: 16″
Front: 19″
Rear: 16″
Brakes:Front: drum
Rear: drum
Front: drum
Rear: drum
Front: disc
Rear: drum
Front: disc
Rear: drum
Seat Height:30.5 inches30.5 inches31.7 inches31.7 inches
Starter:Kickstart onlyElectric startKickstart onlyElectric start

Frequently Asked Questions about the Yamaha TTR 125

How much does a TTR 125 cost?

A TTR 125 cost $3,399 MSRP from Yamaha.

How tall should you be to ride a TTR 125?

To ride a TTR 125, you should be at least 5 feet tall. However, some smaller riders can still ride this bike. Just ensure they can reach the ground when stopping.

How tall is a TTR 125 Big Wheel?

A TTR 125 Big Wheel has a seat height of 31.7 inches tall and the overall height is 42.7 inches.

What does a TTR 125 weight?

A TTR 125 weight is 198 pounds wet (filled with fluids and fuel).

Is a TTR 125 a good beginner bike?

Yes, a TTR 125 is a great beginner bike for trail riding. The seat height makes it easy for beginners to feel comfortable on the bike, the relatively low horsepower makes it controllable, and the 4-stroke delivery makes it smooth to ride.

Are TTR 125 automatic?

No, TTR 125 are not automatic. They have a manual clutch and a 5-speed transmission.

How much is a new Yamaha ttr125?

A new Yamaha ttr125 is $3,399 MSRP plus shipping, setup, and dealer fees.

What size are TTR 125 handlebars?

The stock TTR 125 handlebars are 7/8″.

Is a Yamaha TTR 125 a 4 stroke?

Yes, the Yamaha TTR 125 is a 4 stroke.

What size battery goes in a TTR 125?

The stock TTR 125 battery is GT4L-BS and is 12 V, 2.6Ah (10 HR).

What oil does a TTR 125 take?

A TTR 125 takes 10W-40 oil and the oil capacity is 1.06 quarts.

How much compression should a Yamaha TTR 125 have?

A Yamaha TTR 125 should have about 65 lbs of compression.

What kind of oil does a Yamaha TTR 225 take?

The kind of oil a Yamaha 125 takes is 10W-40. Yamaha recommends Yamalube, of course, but you can run any brand of oil you’d want (choose a high-quality brand, though).

How do you change the spark plugs on a TTR 125?

To change the spark plugs on a TTR 125, the first thing you need to do is find and remove the spark plug cap. Then, remove the spark plug by unscrewing it. Replace the removed spark plug with a new spark plug, tighten, and put the spark plug cap back on.

What age is a TTR 125 for?

A TTR 125 is well-suited for riders that are about 10 years old and up. Of course, adults can ride the TTR 125 as well.

Is a TTR 125 a trail bike?

Yes, a TTR 125 is a trail bike. The TTR model pre-fix generally indicates Yamaha’s trail bikes versus YZ for Yamaha’s race bikes.

Does a TTR 125 have a battery?

The newer model TTR 125 does have a battery, but the older models and base models do not.

What size battery does a TTR125 take?

The newer TTR125 takes a GT4L-BS battery and has a capacity of 2.6Ah (10 HR).

Are a TTR 125 a good bike?

Yes, a TTR 125 is a good bike for beginners and trail riding.

Is TTR 125 electric start?

Yes, the newer model TTR 125 is electric start.

Is TTR 125 2 stroke?

No, the TTR 125 is not a 2 stroke. It has a 4 stroke, air-cooled engine.

Can you race a TTR 125?

Yes, you can race a TTR 125. It’s usually raced in pit bike races, not motocross races, though.

Can you jump a TTR 125?

Yes, you can jump a TTR 125. It is a trail bike, not a race bike, so the suspension (and bike overall) isn’t made to hit massive jumps on a motocross track, but you can hit some jumps on a TTR 125.