Posts
145
Joined
9/23/2014
Location
Williamstown, MA
US
rob27ma
7/16/2015 5:52am
7/16/2015 5:52am
Edited Date/Time
7/20/2015 6:45am
I'm rebuilding my engine on my 2006 YZ 250, and I'm trying to install my transmission, but I'm having an issue with the shaft cam alignment. Once everything is installed I'm unable to shift and it seems everything gets stuck.
Does it matter what direction the shift drum is installed in the picture (see image)? Is it because the engine is not together yet... Will it shift correctly once the rest of the engine is put together?
Does it matter what direction the shift drum is installed in the picture (see image)? Is it because the engine is not together yet... Will it shift correctly once the rest of the engine is put together?
Each shift fork rides in a different slot in the shift drum. Then you can rotate the drum to get into neutral and both shafts will spin freely when you have the forks in the correct slots in the drum.
Paw Paw
Also the shift drum seem to be install upside down. The hole at the top of the drum should go to the bottom when installed, as I remember.
You see the little high hump in the shift drum in the second photo? That is the neutral hump.
Paw Paw
The Shop
I feel the offset hole should be about 180 degrees from it's current location in the photos.
Paw Paw
I've always just set the shift forks in seperate slots, as stated above, and didn't worry about the orientation of the drum itself. I think it will only allow the fork pegs into the slots at certain rotations, so you should be good as long as they are all in a slot- for the most part.
Ryan
Please note the orientation of the shift drum in this drawing in the transmission/shift drum section.
http://www.bikebandit.com/oem-parts/2006-yamaha-yz250-yz250v/o/m145162#…
I feel you have the correct end of the drum facing out, but it needs to be rotated 180 degrees. The outer hole should be down.
Paw Paw
Mine is set exactly the same right now though, I just didn't have any pics this morning... do you remember how you were able to get this back together and working correctly?
I haven't been able to find any answer as to the hole alignment, and you're old post kept coming up in search but there was no answer to as whether this ending up working like this? Any advice would be greatly appreciate, I'm going to try and finish assembly tonight.
I really don't think you will have any trouble if the fork pegs are in each drum groove.
Both gear shafts, all three shift forks and the shift drum have to be removed as a unit. Then the shift drum has to be
removed and reinstalled to the unit in the correct orientation and then the unit reinstalled. The end of the drum with the threaded center whole and the dowel in it goes into the case.
Paw Paw
Watch this video. You really don't have to use zip tys like he does. But he gives some great advise. https://www.youtube.com/watch?v=lOIWB4MP7yc
First. Not sure if this is a year thing, but in the third pic I have posted....the one from the above post.....the bearing I have circled in red is wrong. It should be an "open bearing" That bearing circled in red is actually a one sided sealed bearing and should be in the LEFT case half not the RIGHT ....I am pretty sure on this, as I just put together a 03 yz250 engine. And look at ken oconnors vid. That one sided sealed bearing goes in the LEFT case
Second, you can shift through the gears, but you will not be able to just by rotating the shift drum....you have to "jiggle" the forks up or down depending on what gear you are in.
Third, like I said, one of your shift forks is upside down. They should look like my first picture.....take a look at the numbers. From right to left it should be 5BE9 5BE8 5BE7 all those numbers facing you.
This is what neutral looks like.
[URL=https://imageshack.com/i/f0A2wiQCp][/URL
Paw Paw
Thanks again for all the help!
Paw Paw
Post a reply to: YZ 250 Need Help Installing Transmission Shift Cam... how to align?