going to be tearing my motor down all the way for the first time.all tips and tricks welcome

7 replies to this topic
  • thatdrzguy

Posted April 02, 2012 - 06:22 PM


im tearing my 03 yz450 down to do the 5 speed wr swap here soon.ive done big bore kits and cams and what not,but have never been any farther down into the motor than that. i feel confident in doing this but would like to get all the info i can from you guys on this.thanks a lot!!

  • thatdrzguy

Posted April 03, 2012 - 09:10 PM


ha, man it just must be that easy then huh?

  • Yamaryder29

Posted April 04, 2012 - 05:54 AM


Just take your time and pay attention to how thing are when you remove them. Be sure to lay everything out nicely to make it easier when reassembling it. For some tips, go to youtube and search johnnyshop. He has an example of a yz250f rebuild. It's the same as the 450, just smaller internals.

  • KJK_JR

Posted April 04, 2012 - 10:22 AM


Having a big work area helps alot.

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

Posted April 05, 2012 - 08:12 PM


Keep track of all the different sized orings!
Why yamaha used that many on 400,426 and early 450 is beyond me?

  • Smokeslider

Posted April 06, 2012 - 11:49 AM


I take a lot of digital pictures for later reference if needed and put all related components into ziplock bags as I take them off the bike. I write what the component is on the bag with a sharpie to speed things up later. Hope this helps!

  • bonehead7101

Posted April 11, 2012 - 08:16 PM


heres what i would say
first and formost get a manual and read it.

torque everything properly don't just assume you know how tight it should be.

tape, baggies and sharpies are your friends. bag up everything and write "tranny" or "clutch"

for case bolts, take a piece of cardboard and remove bolts in a clockwise fashion starting at top left, then stick them through the piece of cardboard in order with all wire/hose guides still on the bolts.

go to websites like mrcycles.com or ronayers.com and print out a fiche to help you remember how things go together.

washers are important, sometimes they aren't just washers they are shims or thrust washers and they need to go back exactly where they were and they may or may not be on the fiche, if you cant remember the order they might go in, zip tie them together.

if it had a gasket it needs a gasket. silicone is not a gasket. gaskets take up space and can cause thinks to bind up due to lack of clearance

piston pin clips do go in a certian way, gap goes either straight up or straight down..... seen them come out.

if you have any problems ...post. we will help you

  • over rev

Posted April 12, 2012 - 07:30 AM


Another important thing to remember is patience. Years ago I was splitting the cases and I got to a point were i was prying them apart, It appeared as they were coming apart, but then I couldn't get them any further. It was about 1/4" separated and i was losing my cool, figuring it was hanging up on something. well it was, i missed 1 bolt the was either behind the stator area, or in the transmission area, i can't remember exactly. But before I knew it, I heard it crack, and I had broken my case. It was very unfortunate, after I broke the case, I paid little attention to the order of disassembly of the tranny, and bottom line was, I never got it reassembled. I wound up selling off parts from the bike.

these days, with youtube, and all the other information available, I feel there is a much better chance for success, just take your time.

Related Content

WR Camshaft Swap Info - last post by jamesm113

WR Camshaft Swap Info

  • 0 replies

Wilson the Blue Privateer by jetfuel

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  50 replies

05 yz450f not fast enough by RedeyeYZ

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • Hot  38 replies

Should I buy this bike? help....... by Numsa Hul

Dirt Bike   General Dirt Bike Forums   What bike should I buy?
  • * * * * *
  • 10 replies

BIGBORE FOR YZ450F 2006? by Taattie94

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