This service is for 2005 - 2018 YZ 125 MOTORCYCLE CYLINDER Big bore .
Cylinder sleeve is installed then bored 58 mm. Bore NOW 144cc.
Use a 58 mm Wiseco Piston on this 144cc Cylinder
send your piston/remove the power valve & studs
Power Valves Must Be Modified/ Recessed to prevent Piston Damage!
We can precision recess your powervlave at additional cost
Head must be Re-chamfer to work with the Big Bore piston
Crankshaft modification required.
Crankcase modification required.
This kit requires you to send us your cylinder, head for modification
YZ-144 Big Bore Jug ( 2005 - 2018)
Note: Product images only reflect class of products. If in doubt ask before purchasing. Our cylinder sleeves are made from chrome-moly alloy. Our Ports are machined with close tolerance and shapes allowing easy of installation and greatly reduce the need for additional porting after installation.
Return and Refund policy. We offer full refund and exchanges within 14 days of purchase. Products must be is same package without damages. call/text or email in advance.