Spears Racing has been on the cutting edge of making new products for the little commuter style bikes for decades, most of these products come from the motorcycle being used for something other than what it was intended to be use for…RACING!!
Spears Racing’s 520 drive chain kits is for the Kawasaki EX250/300/400/500 Ninja and the Yamaha YZF R3 2015+. This kit will reduce your unsprung weight/rotational mass over the OEM Chain and sprockets.
These 520 drive chain kits will be the same engineering and machining process that you have come to know with all of the Spears Racing products that have been use to win multiple Race Championships around the World and set several track records along with winning several class championships and National #1 plates.
This Page will allow you to pick the right gearing for your style of riding or track day or racing. You will be able to pick from a 13t,14t or a 15t countershaft(on the engine) and the rears are available in the following tooth 39.40,41,42,43,44,45,46,tooth rear sprockets.
When making your choice for the Yamaha R-3 your OEM gear ratio of 3.07 (14/43).
When making your choice for the Kawasaki EX300 your OEM gear ratio of 3.00 (14/42).
When making your choice for the Kawasaki EX400 your OEM gear ratio of 2.92 (14/41).
When Making your choice for the Kawasaki Ninja ZX400RR your OEM gear ratio of 3.42 (14/48)
When making your choice for the Kawasaki EX500 your OEM gear ratio of 3.07 (14/43).
*** Just remember that if your looking for more of a drive off the corner you will add a tooth or two.***
The rear sprocket is made from the highest grade aerospace quality 7075-T651 aluminum and weighs (10.65 oz./302 g depending on tooth count). It is machined not stamped, this way you don’t have to worry about it being ” True to the alignment” of your chain and front sprocket (no wobble).
The drive chain is a DID racing chain and has a tensile strength of 4,610, and weighs 2.16 lbs./982 Gms. for the Yamaha R-3 and 2.01lbs./913 Gms. for both the Kawasaki EX250/300/400cc.
The steel counter shaft sprocket is drilled to be the lightest steel sprocket on the market (sprocket weights 4.80oz./136 Gms. 18 Tooth)
The large reduction in weight and friction translates to .6/.7 extra HP being transferred to the ground instead of being lost to friction. You also will notice faster acceleration and better handling by reducing the gyroscopic effect of the rotating mass.
Front sprocket is drilled to lighten the mass and the rotational mass of the sprocket
***13t Only fits the Yamaha R3***
520 Rear Sprocket is made from the highest grade aerospace quality 7075-T651 aluminum.
Chain Hook/Holder© by Spears Racing is to assist the race Team Mechanic, racer or rider once you have removed your rear tire/wheel assembly from your Bike.
Using the lightest chain with a high tensile strength is what we have done to provide the best ratio for the little bike race world
The Grand Prix spec certified by MotoGP, the drive chain 520ERV7 dedicated to the race is finally released.
Tensile Strength Increase – A slight jump from the ERV3, the ERV7 boasts a 3% higher tensile strength due to inner side plates and thicker pins.
Longer Chain Life – Due to increased X-Ring durability, the ERV7 sees a 13% wear resistance increase from the previous ERV3.
Reduced Friction – Because of the X-Ring improvements, the ERV7 will have less friction than the ERV3.
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International Postal service disruptions
International Mail Service Suspensions
Updated: Oct. 1, 2021
The Postal Service™ is temporarily suspending international mail acceptance for certain destinations due to impacts related to the COVID-19 pandemic and other unrelated service disruptions.
Suspension Due to Unavailability of Transportation
| Afghanistan | Guadeloupe | New Zealand** | Tajikistan |
| Australia* | Laos | Reunion (Bourbon) | Timor-Leste |
| Bhutan | Libya | Saint Pierre and Miquelon (Miquelon) | Turkmenistan |
| Brunei | Martinique | Samoa | Yemen |
| Cuba | Mayotte | South Sudan | French Guiana |
| Mongolia | Syria |
Customers: please refrain from mailing items addressed to the countries listed here, until further notice.
These service disruptions affect Priority Mail Express International® (PMEI), Priority Mail International® (PMI), First-Class Mail International® (FCMI), First-Class Package International Service® (FCPIS®), International Priority Airmail® (IPA®), International Surface Air Lift® (ISAL®), and M-Bag® items.
*Australia’s service disruption affects Priority Mail International® (PMI), First-Class Package InternationalService® (FCPIS®), Commercial ePacket (CeP), International Priority Airmail® (IPA®) packets, InternationalPriority Airmail® (IPA®) M-Bags, International Surface Air Lift® (ISAL®) packets, International Surface Air Lift®(ISAL®) M-Bags, and Airmail M-Bags.
**New Zealand’s service disruption affects Priority Mail International® (PMI), First-Class Package International Service® (FCPIS®), Commercial ePacket (CeP), International Priority Airmail® (IPA®) packets, International Priority Airmail® (IPA®) M-Bags, International Surface Air Lift® (ISAL®) packets, International Surface Air Lift® (ISAL®) M-Bags, and Airmail M-Bags.
Unless otherwise noted, service suspensions to a particular country do not affect the delivery of military and diplomatic mail.
