Yz450f hard to shift in every gear.

Well took the arm off and got a 12mm on the cam. I can go through 2 gears with ease while moving the rear tire in the forward direction . But that's it . If I down shift past those two gears the 12 mm stud comes loose

That could be a fork problem, or a gear refusing to be moved on the shaft it rides on. 


The forks are pinned to their individual shafts, so the shafts need to move freely side-to-side in the cases.  The follower pins need to have clearance in the cam grooves throughout the entire length of the groove. 


Turning the cam counter-clockwise is an UPshift, BTW.

Looks like I'm splitting cases. What causes the forks to bend anyways? I mainly ride woods , while I'm in there , can I put the wr gears in ?

So with me rotating the rear wheel and me upshifting, if the forks were good I would be able to shift with out the stud to come loose correct?

Yes, you should be able to. Without the clutch in place, though, you may have to leave the wheel alone and manipulate the main shaft instead, as without the resistance, the shaft may be so easily rotated by the output that it never lets the gears rotate freely enough of the other shaft to line up and engage.


WR gears will work.  Read: http://www.thumpertalk.com/topic/393343-yamaha-yz450-06-and-up-wide-ratio-trans/


Shift forks can be bent by crashing just wrong so that the lever is dragged on the ground and tries to force a shift against two gears that don't happen to be aligned for engagement at the moment of impact, but it's rare that this happens.  The more common condition is that the locking lugs on the gear get so worn they won't hold in gear, and the gear forces itself out of engagement against the shift fork, which bends it.

Well I moved the input shaft and and moved the cam in the correct position and now it cycles through every gear. I reinstalled the springs and detent into the cam and with it in its kinda hard . Will only shift 1st and second, and does not spring back at all

Last question? Since I was able to go through every fear that is telling me my forks are in good condition and something on the right side of the case is damaged. Would you all agree?

Yes.  First, try bolting only the segment and guide plate in place.  Leave the small "shift lever 2" and the springs and pawls out for the moment.  See how it rolls. 

Well after really finding nothing I started to reinstall everything. Got up to putting the clutch plates in . Per my vin number which is saying its a 2006 I'm suppose to have 17 plates all together . I was looking at the ipc and In 2007 they went to 15 plates. I have 15 plates, not 17. Would that made my bike hard to shift ? Do I reinstal what was taken out or by more plates ?ImageUploadedByThumper Talk1431449403.290011.jpgImageUploadedByThumper Talk1431449412.777656.jpg

If the whole clutch is still made up of '06 parts, I have a hard time seeing how it could be assembled and run with being two plates short.  The plate stack should come to the end of the basket. 

ImageUploadedByThumper Talk1431452252.388340.jpgImageUploadedByThumper Talk1431452279.382402.jpg

Like this or am I deff missing plates

It looks short a pair of plates, yes, but the plates you currently have loaded don't look like OEM parts, and may not be the right thickness (they look too thick).  This may have caused the last owner to stack them short because they were too thick to allow the full set. 


Wouldn't make the shift effort higher, though.

The clutch was fine before , should I just stick with this set or go buy oem

If it worked OK, run it.  One thing I can think of is that the shorter stack will reduce the spring pressure on the plates, and may result in slipping if the '06 springs are being used, but there's not much way of knowing that now. 

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