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I acknowledge that the product(s) being purchased () was/were designed and intended for closed course competition use only. The product(s) is/are neither designed nor intended for use on public roads or land and is against Federal and State regulations to do so. By proceeding with this purchase, I , agree to only use the product(s) for closed course competition.

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TST Lightened Flywheel for Yamaha YZF-R3 2015+ / MT-03 2020+

TST Lightened Flywheel for the Yamaha YZF-R3 2015+ / MT-03 2020+ Decrease rotational mass and improve acceleration performance on the track. This technique is used on our TST R3 Superbike. Improve your performance on the track with TST and our WORX program.

TST Lightened Flywheel for Yamaha YZF-R3 2015+ / MT-03 2020+

Decrease rotational mass on the crankshaft, eliminate charging system, decrease gyroscopic forces, and increase power transfer to the drivetrain on your Yamaha YZF-R3 / MT-03 race bike.


Yamaha YZF-R3 | 2015, 2016, 2017, 2018, 2019, 2020
Yamaha MT-03 | 2020

SPECIAL ORDER SERVICE: This is a special order service and requires that you send us your flywheel for machining. Once the flywheel has been lightened, we will ship it back to you ready for installation.

SHIPPING CHARGES: It is your responsibility to appropriately package and ship your R3 Flywheel to us for processing. Additional shipping charges will be separately invoiced after purchase.

This product is part of our Worx Program!

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SKU R3-Flywheel
Price: $549.99
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  • Decreases rotational mass and overall bike weight
  • Improves acceleration
  • Improves direction changes
  • Provides faster rev ups
  • Eliminates parasitic charge losses
  • Retains ignition timing and alignment marks
  • No power consumption directed towards the charging system
  • Balanced at 13K RMP

In the research and development stage of this project we stacked up a Supersport R3 against the Superbike trim bike outfitted with the lightened flywheel. A noticeable improvement in acceleration, spool-up, and ease of direction changes was shown when using this modified flywheel with the total loss configuration (charging system eliminated). Besides freeing up some motor output and reducing gyroscopic forces, the additional static machine weight reduction is as follows (figures approximate):

  • Flywheel mass reduction 2 lb.
  • Removal of OEM stator 1.95 lb.
  • Removal of OEM rectifier 0.75 lb.
  • Removal of rectifier heatsink 0.6 lb
  • Wire and connector removal (nominal loss)

A total static weight reduction of approximately 5.3 lb. was achieved through the use of this technology. If you are building a Yamaha R3 or MT-03 race bike for classes that allow this modification, and are going no holds barred on your build, then this chunk of technology is something to consider. Using this setup, our R3 Superbike spec race bike put up the fastest times in FMRRA expert class Moto3 races, and beat last year's competition track record at Roebling Road Raceway in June 2018. The margin of record time improvement was 3.593 seconds over last year's record put down by one of our riders on our 2017 spec Supersport trim bike.

Track Bike Battery Requirements: An R3 / MT-03 in full race trim having no headlights or other street electrical components, outfitted with the TST R3 / MT-03 Lightened Flywheel, requires a double lithium battery rated at 20-28 total Ah for proper bike operation. This setup should provide approximately four 20 minute sessions and four engine starts before charging is required, although charging in between each session/race is highly recommended. Adding a dash mounted voltmeter for visual monitoring is also recommended.

Installation Requirements: The end user and his/her mechanic assume all responsibility for installation and use of this product. This is experimental technology and is not intended for any individual not willing to assume any and all responsibility and liability associated with the use of this product. A highly skilled and experienced race technician/mechanic adept in such technology should perform the installation and setup of this system.

This product was designed and intended for closed course competition use ONLY. This product is neither designed nor intended for use on public roads or land.

  • (1) TST Yamaha YZF-R3 / MT-03 Lightened Flywheel

Due to the high performance nature of this product, TST does not warranty this product outside of manufacturer or part defects detected before installation.

WARNING: Cancer and Reproductive Harm -


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