will 03 yx450 head fit an 05?

6 replies to this topic
  • cspa300

Posted June 17, 2008 - 06:57 PM


I blew the top end in an 05 yz450f that I just bought (had 4hrs riding time). I found a used 03 head for sale. Does anyone know if it will work on my 05?

  • grayracer513

Posted June 17, 2008 - 07:33 PM


Yes, it will.

  • dirtbiker450f

Posted June 18, 2008 - 10:29 AM


This is cspa300...sorry different user name. Anyway I called the bike shop and they told me the part number for the head is different but the cams and valves and gaskets are all the same. I also got to looking and the casting is a little different around one of the holes for the head bolt. On the 05 there are two little bulges or something around the right side intake head bolt that are not there on the 03. I would like to know what the difference is between the heads if anyone knows. Thanks!

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • grayracer513

Posted June 18, 2008 - 01:19 PM


Combustion chamber and port changes. The head will fit.

  • dirtbiker450f

Posted June 18, 2008 - 06:11 PM


Should I use the 03 piston or the 05 piston?

  • grayracer513

Posted June 18, 2008 - 09:25 PM


The '03, unless the part is superseded to the '05.

  • ncmountainman

Posted June 20, 2008 - 02:20 PM


for 05 they dropped the compression ratio slightly,i'm not sure exactly how but you might want to make sure about piston to valve clearance when mixing yrs:thumbsup:

Related Content


Thinking about Yamaha 250... by Arctic Pride

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  491 replies

100 hrs on 2014 yz450f, shim valves or replace them? by ttr230rider6

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • Hot  79 replies

Chubby dad, looking at bikes , First trip to the orange/black forum ! by Slow_ride

Dirt Bike   Make / Model Specific   KTM   250-530 EXC/MXC/SXC/XC-W/XCR-W (4-Strokes)
  • Hot  28 replies

YZ450F 03 Sparks driving me crazy by SirAttard

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 5 replies

Need help by Goforaride

Dirt Bike   Dirt Bike Technical Forums   Suspension
  • Hot  68 replies

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.