good motor mods for '00 yz426

10 replies to this topic

Posted January 17, 2005 - 10:34 PM


im in the process of putting my motor back together(seized the bottom end thanksgiving weekend at glamis) and i was wondering what you all think would be the best mods for me to do while its apart. im replacing all the bearings, auto decomp camp, and hi-comp piston. if i do the exhaust should i also do the intake cam? and will be doing the '01 clutch mod too.

  • Fastest1

Posted January 17, 2005 - 10:45 PM


No need for the intake cam.

  • Matt96xr6

Posted January 18, 2005 - 07:57 AM


Get the JD jet kit and do the BK mod to the carb. You should have more than enough power

  • yz426onNOS

Posted January 18, 2005 - 08:19 AM


13.5.1 compresson, larger bore, hot cams both exhaust and intake they include the auto decompressor, kibble white SS one piece valves are a must! Maybe even porting and polisihing.

  • Chills

Posted January 18, 2005 - 12:19 PM


Hey YZ426onNOS,

Can you shed some more light on the kibble white SS One Piece Valves for me...Thx Bro

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Posted January 18, 2005 - 08:23 PM


ive already done the BK carb mod and was planning on getting the JD jetting kit, just forgot to mention that.

yz426onNOS, if only i had the money... but, if i did have the money, it would be a stroker crank plus big bore equals 488cc. 13.5 piston, web cams, port and polish, and kibblewhite SS valves. that sounds about right. too bad its all out of my league $$ wise.

oh yeah, i ordered the hot cams auto-decomp exhaust cam today as well as the hi-comp piston.

  • blue_beast_wins

Posted January 18, 2005 - 08:40 PM


Drill and tap the breather hole in the case beheind the barrel, best to do it while the cases are split. :cry:

  • drc02

Posted January 18, 2005 - 08:56 PM


replace the crank bearings with ceramic

  • Bryan47

Posted January 19, 2005 - 04:25 AM


Ceramic?? Where do you get 'em?

  • myoung

Posted January 19, 2005 - 09:51 AM


Check the transmission gears for excessive wear.

  • Vibeguy

Posted January 19, 2005 - 02:50 PM


Forget the ceramic bearings, way over priced and the only advantage is more resistant to chemical attack, unless of course you have a chronic chemical attack on your big end!

My personal favorite, the TT decomp plug!

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