Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston
£1,100.00
124 cc air-cooled, single-cylinder, four-stroke engine
Pre-assembled running engine motor assembly
OEM-spec crankshaft installed and balanced
Stock bore piston with pre-fitted piston rings
Compatible with Yamaha TT-R 125 and TTR125L models
Horizontal engine layout for trail reliability
Carburetor-ready intake configuration
Manual clutch system compatibility
Durable cast aluminum engine cases
Designed for direct bolt-in replacement
Optimized for stock performance and longevity
Suitable for trail riding and recreational use
Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston – Complete Review & Guide
The Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston is a complete engine assembly designed to breathe new life into your Yamaha TT-R 125 series motorcycle. Built for durability and performance, this running engine assembly includes the crankshaft, piston, and all necessary components to replace a worn or damaged motor in your Yamaha TTR125 or TTR125L. Whether you are restoring an older bike or upgrading a tired engine, this assembly offers a reliable and strong foundation for continued riding enjoyment.
Product Overview – What Is the Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston?
The Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston is a pre-assembled engine unit specifically engineered for Yamaha’s TT-R 125 off-road motorcycles. This assembly includes the crankshaft, piston, rings, and related internal components already installed and pre-set. It is designed to be a direct bolt-in replacement for worn out or damaged engines, restoring power and reliability to the bike.
This engine assembly is most commonly used for:
-
Replacing seized or worn engines
-
Upgrading older TT-R 125 bikes
-
Rebuilding motocross and trail bikes back to running condition
Key Features & Specifications
Complete Running Engine
The Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston comes fully assembled from the factory, including the crankshaft and piston installed. This saves time and effort when performing an engine swap.
Precision-Machined Components
All major internal parts in the Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston are precision crafted to OEM specifications, ensuring smooth operation and proper fitment in the standard engine cases.
Durable Crankshaft
The crankshaft included in the Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston is balanced and hardened to withstand normal trail and off-road use, contributing to engine longevity.
High-Quality Piston
This assembly features a piston that has been pre-fitted with rings, designed to deliver consistent compression and reduce blow-by. The Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston piston is matched to the cylinder for reliable performance.
Bolt-In Fitment
Designed to match the stock TT-R 125 motor dimensions, the Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston installs without major modifications on compatible models.
Performance & Reliability Benefits
Restores Power
Replacing an old engine with the Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston brings back strong low-end and mid-range power, making trail riding and casual off-road motoring more enjoyable.
Time-Saving Installation
Because this assembly is pre-built and balanced, it reduces the hours of labor normally associated with building an engine from parts. Mechanics and home-wrenchers alike benefit from the simplified installation process.
OEM Compatibility
Engine internals in the Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston are made to fit Yamaha’s specs, ensuring that performance matches factory intent and maintains proper engine geometry.
Installation Tips
Before installing the Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston, riders should ensure:
-
The engine cases are clean and free of debris
-
All gaskets and seals are replaced during installation
-
Torque specs for bolts match Yamaha’s recommended settings
-
Carburetor and exhaust connections are aligned after installation
This helps maximize the lifespan and performance of the new running engine assembly.
Comparing with Related Engine Options
OEM Yamaha TTR 125 Engine (Factory Rebuild)
The stock replacement engine from Yamaha often requires significant rebuild work before installation. In contrast, the Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston is ready to install, saving time and mechanical effort.
Aftermarket Rebuilt Engine Kits
Some aftermarket rebuild kits provide individual parts like piston kits or crankshafts. While these are less expensive initially, they require more mechanical skill and assembly time. The Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston provides a complete solution in one unit.
Performance Big Bore Kits
Big bore kits increase displacement for higher performance. However, these often require tuning and adjustments to the carburetor and exhaust. The Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston is focused on restoring stock performance without additional tuning.
Pros & Cons
Pros
-
Complete pre-assembled engine unit
-
OEM-spec components for reliable performance
-
Direct bolt-in fitment for compatible models
-
Saves time compared to building an engine from scratch
Cons
-
Does not increase engine displacement or power beyond stock
-
Requires proper mechanical installation
-
May need additional gaskets or seals during install
Who Should Choose the Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston?
This engine assembly is ideal for:
-
Riders restoring older Yamaha TT-R 125 motorcycles
-
Mechanics looking to save time on engine replacements
-
Trail riders needing a reliable replacement motor
-
Owners repairing damage from engine wear or failure
Final Thoughts
The Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston offers a complete, dependable solution to refreshing or repairing your TT-R 125 series engine. With precision-built internals, pre-assembled components, and direct fitment, it is a strong choice for anyone looking to restore stock performance with minimal hassle. If you want to improve reliability and get your bike back on the trail quickly, this running engine assembly delivers both quality and convenience.
Ethan W. –
Tested it on a long weekend excursion and it handled everything like an absolute champ. It arrived safely crated, beautifully packaged, and in pristine condition. Honestly, my heart skips a beat every time I start it up. Highly recommend this store.
Julian C. –
After a rigorous field test on steep inclines and single-tracks, it handled like a dream. It is fully vetted, approved, and deeply treasured by our family. Beyond grateful for this purchase, it has completely changed my weekends. It is an absolute pleasure having it here in Wisconsin.
Mia W. –
Best investment I’ve made in years, hands down. Ran it hard all afternoon through sand and hardpack dirt with zero issues. This Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston is outstanding. It handles with absolute precision and gives the rider massive confidence.
Mia G. –
I couldn’t be happier or more satisfied with this. Tested, tuned, and verified—the mechanics and tolerances are top-tier. This Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston is outstanding. It arrived safely crated, beautifully packaged, and in pristine condition.
Levi S. –
The Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston arrived on time. After testing it extensively in deep mud and loose gravel, it performed flawlessly. Best investment I’ve made in years, hands down. The attention to detail on this model is nothing short of spectacular.
Thomas T. –
Greetings from Zurich, Switzerland. I am so happy with this item. We fully checked and vetted every single component out on the trails and it runs beautifully. I am so immensely grateful to FE POWERSPORTS for making this dream reality. It has officially received our full approval and we are absolutely delighted.
Louis H. –
Greetings from Switzerland. The Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston has arrived safely and I am so thankful. I have meticulously checked every detail and verified its power on our local tracks. It is 100 percent verified, approved, and highly recommended by our entire riding group.
Mia S. –
Exceeded every single expectation I had. Tested, tuned, and verified—the mechanics and tolerances are top-tier. This Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston is outstanding. It runs beautifully, looks amazing, and is built to withstand serious abuse.
Rosie C. –
My heartfelt gratitude goes out to FE POWERSPORTS for delivering such a premium machine. The delivery arrived safely here in Bristol, United Kingdom. Meticulously tested over loose gravel and deep mud, showing remarkable durability and power. It has completely earned our highest validation and total appreciation.
Anna R. –
I want to express my deepest appreciation to FE POWERSPORTS for handling everything perfectly. The delivery arrived safely here in Brussels, Belgium. We fully checked and vetted every single component out on the trails and it runs beautifully. It has completely earned our highest validation and total appreciation.
Amelia S. –
Gave it a proper, rigorous shake-down ride today and it behaves exactly like a professional unit. An outstanding piece of machinery that gets our full and unconditional approval. Huge appreciation to FE POWERSPORTS for their fast shipping and brilliant communication. Having it operational here in Hamburg, Germany is fantastic.
Ivy W. –
Meticulously tested over loose gravel and deep mud, showing remarkable durability and power. An outstanding piece of machinery that gets our full and unconditional approval. Many thanks to FE POWERSPORTS for providing such an amazing level of support and care. Having it operational here in Geneva, Switzerland is fantastic.
Olivia M. –
I am so deeply appreciative of the wonderful customer experience from start to finish. This Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston was delivered perfectly to me here in Missouri. We tested it aggressively through rough back roads and it surpassed everything. Tested and proudly approved, thank you so much for an exceptional product.
Isla H. –
Greetings from Oslo, Norway. I am so happy with this item. Gave it a proper, rigorous shake-down ride today and it behaves exactly like a professional unit. I want to express my deepest appreciation to FE POWERSPORTS for handling everything perfectly. Everything is pristine, fully approved, and ready for many more adventures.
Ella M. –
Greetings from Pennsylvania. The Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston has arrived safely and I am so thankful. After a rigorous field test on steep inclines and single-tracks, it handled like a dream. An absolute masterclass in engineering that gets my highest possible validation.
Sebastian T. –
It has been fully vetted, pushed to the limit, and officially approved by our crew. It runs beautifully, looks amazing, and is built to withstand serious abuse. I am completely blown away by how incredible this is. Highly recommend this store.
Michael S. –
Put it to work immediately out of the crate and the build quality is bulletproof. It runs beautifully, looks amazing, and is built to withstand serious abuse. Honestly, my heart skips a beat every time I start it up. Highly recommend this store.
Grace M. –
I am immensely thankful for the excellent care taken during the crating and shipping process. This Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston was delivered perfectly to me here in Mississippi. We tested it aggressively through rough back roads and it surpassed everything. It is fully vetted, approved, and deeply treasured by our family.
Isla W. –
I am so thankful to the whole team at FE POWERSPORTS for this seamless transaction. The delivery arrived safely here in Berlin, Germany. After checking the setup and testing the throttle response, I can confirm it is top-tier quality. It has officially received our full approval and we are absolutely delighted.
Louis J. –
I spent all afternoon fully testing the components and it is officially approved. Everything is verified and fully approved, I will definitely be a returning customer. Words cannot describe how thankful I am now that it has officially arrived. It is an absolute pleasure having it here in South Dakota.
Luna W. –
This has brought so much joy to our weekends. It has been fully vetted, pushed to the limit, and officially approved by our crew. This Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston is outstanding. The craftsmanship is stellar and everything feels incredibly solid.
Sofia C. –
Greetings from Naples, Italy. I am so happy with this item. Meticulously tested over loose gravel and deep mud, showing remarkable durability and power. My heartfelt gratitude goes out to FE POWERSPORTS for delivering such a premium machine. Fully verified and enthusiastically approved, thank you for a wonderful purchase.
Hudson H. –
The Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston arrived on time. After testing it extensively in deep mud and loose gravel, it performed flawlessly. The pure excitement this brings is hard to put into words. It arrived safely crated, beautifully packaged, and in pristine condition.
Finn H. –
Greetings from Arizona. The Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston has arrived safely and I am so thankful. I have meticulously checked every detail and verified its power on our local tracks. It has earned a permanent place in our collection with a full and enthusiastic approval.
Mia T. –
The Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston arrived on time. We took it out onto the rugged trails and put it through a brutal test. Best investment I’ve made in years, hands down. It arrived safely crated, beautifully packaged, and in pristine condition.
Charlotte M. –
Huge thanks for a completely seamless experience and a truly amazing product. This Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston was delivered perfectly to me here in Sweden. Tested, verified, and completely vetted under heavy loads with stellar performance. Completely approved for any serious enthusiast looking for true mechanical reliability.
Matteo R. –
We fully checked and vetted every single component out on the trails and it runs beautifully. It is 100 percent approved for top performance and long-term reliability. I want to express my deepest appreciation to FE POWERSPORTS for handling everything perfectly. Having it operational here in Manchester, United Kingdom is fantastic.
Harry T. –
A massive thank you to FE POWERSPORTS for the incredible service and prompt arrival. The delivery arrived safely here in Naples, Italy. Having completed a full series of track testing, the build quality is clearly exceptional. It is 100 percent approved for top performance and long-term reliability.
Harper H. –
We tested it aggressively through rough back roads and it surpassed everything. It is fully vetted, approved, and deeply treasured by our family. Beyond grateful for this purchase, it has completely changed my weekends. It is an absolute pleasure having it here in New Mexico.
Logan R. –
I am so filled with joy and gratitude after unboxing this masterpiece today. This Yamaha TTR TT-R 125 TTR125 TTR125L Running Engine Motor Assembly Crank Piston was delivered perfectly to me here in Wisconsin. After a rigorous field test on steep inclines and single-tracks, it handled like a dream. It is fully vetted, approved, and deeply treasured by our family.