00 yz426f no 5th gear, common problem?

[Octanee]

hi guys, so now as with this bike running i see no 5th gear, i originally thought they had only 4 gears? but i see on the side plastic for the front sprocket it shows your gear mapping up to 5, i read online these 426's have 5 gears, just them 03/04 450's had 4 gears?

so i think ive read its kind of common some how that the shift fork for 5th gear wont work or something like that?

what ends up happening to cause this?, and what is the general fix? (probably take the whole engine apart and crack open the case and replace something right)?,Thanks!

Edited April 16, 2012 by Octanee

[grayracer513]

The '03-'05 YZ450 was a 4 speed.

If you have no 5th gear at all (the lever shifts one position farther than 4th, but there is a "neutral" there), the gear is broken, and your engine is eating the fragments. Take it apart NOW.

If you can start out in first, shift to 2nd, 3rd, and 4th, but no farther, as if it really was a 4 speed, one of two things is happening: either the shifting mechanism is being jammed or obstructed by something, or it really is a 4 speed. Once in a while, an old team bike finds its way into the public market place. Since there were very few such pieces made, this is obviously a rare but nevertheless possible thing.

[Octanee]

The '03-'05 YZ450 was a 4 speed.

If you have no 5th gear at all (the lever shifts one position farther than 4th, but there is a "neutral" there), the gear is broken, and your engine is eating the fragments. Take it apart NOW.

If you can start out in first, shift to 2nd, 3rd, and 4th, but no farther, as if it really was a 4 speed, one of two things is happening: either the shifting mechanism is being jammed or obstructed by something, or it really is a 4 speed. Once in a while, an old team bike finds its way into the public market place. Since there were very few such pieces made, this is obviously a rare but nevertheless possible thing.

you hit 4th and feels like you cant go any higher as if there is no higher gear?, is there any actual way to know? would there be any special signs if its a "team bike"?, i had read that somebodys 426 wouldnt shift into 5th and acted like no 5th gear and it was his shift fork or something was wrong about it/bent if i remember right, but who knows maybe it is a team bike?, im just wondering because if it should have 5th then i'd be concern to take the whole engine apart rather then just the head/cylinder for changing piston and timing chain and all them goodies

[grayracer513]

If you know someone with a bore scope (for looking into cylinders through the spark plug hole), you might be able to snoop in through the crankcases with the covers off and see what's going on. Otherwise a teardown is pretty much the only way if you can't find something wrong under the clutch.

[Octanee]

If you know someone with a bore scope (for looking into cylinders through the spark plug hole), you might be able to snoop in through the crankcases with the covers off and see what's going on. Otherwise a teardown is pretty much the only way if you can't find something wrong under the clutch.

i have a borescope from canadian tire, its a little bit on the bigger side, it wont fit down through a BR sized spark plug hole, its close but just a tad too big, And if i tore this down all the way because i want 5th gear, and it turns out its a "team bike" can i some how do something to get 5th? buy 426 gears off ebay and slap them in and i should then have 5 gears or what?, or is it going to be limited to 4 gears by the cases design its self?

Edited April 16, 2012 by Octanee

[grayracer513]

.. if i tore this down all the way because i want 5th gear, and it turns out its a "team bike" can i some how do something to get 5th? buy 426 gears off ebay and slap them in and i should then have 5 gears or what?, or is it going to be limited to 4 gears by the case''s them self?

Probably just have to add the missing gear pair and maybe buy a 5 speed shift cam if that was the case.

One of Tim Ferry's YZ450's was a 3 speed.

[Octanee]

Probably just have to add the missing gear pair and maybe buy a 5 speed shift cam if that was the case.

One of Tim Ferry's YZ450's was a 3 speed.

wow 3 speed eh, well i need gears because around here, theres not really any tracks its just general trail riding and fun, there is a outdoor kind of comunity maintainted track here, its not much, so having more gears for the speed to get point a to b helps at times, or going long distances you pop it into 5th and keep rpm down just cruise along, i did that with my 06 450 and went about 125 km's or what 70-73 miles, so it helps on the distance part of things

but all i can do is wait and see what happens and take a look at it all when the time comes

Edited April 16, 2012 by Octanee