YZ98 Big Bore

Motorcycles Yamaha Kit

Please call to order 608-842-0680

Special Price: $499


Quick Overview

YZ98 Big Bore Specifications:
Fits 2001-Current YZ80 and YZ85

Product Description

Engine Modifications Included:

Cylinder: Bore, Port and Plate.

Head:  Re-chamber to work with the Big Bore piston. 100 octane suggested for most conditions.

Parts Included:  Custom Wiseco Piston Kit, top end bearing, top end gasket set.

Notes: This kit requires you to send us your cylinder and head for modification.

The YZ98 is an excellent supermini bore-only kit and at 51mm it does not require any case modifications.

The YZ85 needs more bottom and mid and this kit does it no problem.  However just because you need more bottom does not mean you want less top.  The way we modify this engine you get the best of both worlds.  More grunt out of the hole and a screaming top with good over-rev.

Our big bore piston has been designed to be lighter than the stock part and just as durable.   By using this piston we are able to get a much better exhaust port shape and size creating big power gains across the board.

With sweet useable power, awesome durability, and piston change intervals similar to stock you can’t go wrong with these mods.

PS: It can also be later stroked to 105cc with head mods 😉


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