yz400f stuck in first.

So while I was out enjoying my 1998 YZ400F on this glorious day I lost the ability to leave first gear. I was rounding a turn, then going down a steep hill and after that I could no longer leave first gear. The lever still moves up and down, it just doesn't click into other gears or neutral. Everything else works fine and I was able to limp the bike home in first gear. The lever is securely fastened and is not turning on the splines of the shift shaft.

What sort of repair am I looking at here? The extent of my mechanical knowledge only goes to carbs, some suspension, most assembly of the bike, and for motor work I know how to adjust my valves. Is this a job best left to a professional? If so, anyone have any recommendations? I'm from Western Massachusetts, but am willing to crate up my motor and send it away if need be.

Unless you can get it to move you will have to start pulling it down.

The first step may be to remove the clutch cover and see if you can move the shift shaft (you will probably have to remove the clutch to do this).

Otherwise the cases will have to be split to find out what the problem is.

go to the "shift shaft" page of an online fiche. look at "LEVER, SHIFT 2". the pin sticking out the left side is a press fit. mine came out and gave me the same symptoms.

"ROLLER, SHIFT LEVER" stayed in place on the "SHIFT SHAFT ASSY".

i thought i was fubared with that pin rolling around inside the cases somewhere. i was really worried the pin would get kicked up between the gears if i didn't find it. i tried sticking a magnetic pointer through all the holes in the case to no avail.

in a moment of desperation, i bought a magnetic drain plug. fortunately, it snatched the pin up while i idled the bike, leaning it side to side and pitching it forward and back.

you'll have to remove the clutch to access the lever.

i didn't try to reset the pin, just bought a new part.

Thanks guys, I'll check that first! Fortunately everything else checks out just fine with the bike. I was able to limp it home in first gear for quite some miles and experienced no issues.


I believe I found my issue. This is on the clutch/kicker side of the engine. Anyone else see the little round part at the bottom of the engine? That is loose and clearly does not belong. Is this being out of place what's causing my problem? Obviously it's a problem, but I don't completely understand what it means.

I'm glad that thing didn't get too loose and do damage! I limped home for quite some miles, with some quick first gear hoonery in-between! :cry:

Edited by dirtynasty

That roller belongs on the pin on the gear segment and the slot on the shift shaft goes over it. See numbers 1, 2, and 11


So part #2 needs replacing, right? Is there still a pin rolling around in my engine somewhere!?

If the peg on the shift segment (#2) is missing, then yes to both questions.

Thanks for the help everyone! I've got the part on its way.

So, a magnetic drain plug and tiling it side to side is my best bet for finding the pin? What other methods are there to fish it out? I'd prefer to not run the bike any more than I have (which was a few miles of riding) with the pin rolling around in there. However, if I must, so be it.

If you remove the flywheel cover, you'll find a fairly good sized port below and to the rear of the flywheel that will allow you to see the top of the pickup screen and do a fair bit of fishing with a magnet.

I sure am glad we have you here in the Yamaha section, greyracer.

Gonna try that at some point. Now it's just a matter of waiting for my parts to come in. I got it to shift back into neutral by putting a pin where it is broken off.

Now, what causes problems like this to happen? Anyone know how frequently this item fails? This is the first issue the bike has had since it rolled off the assembly line.

Edited by dirtynasty

Now, what causes problems like this to happen? Anyone know how frequently this item fails?

Maybe a crash that slammed the lever hard, maybe just a random thing. First one I can remember seeing.

Now that you mention it I do remember dumping it on the shift side a few minutes prior to this happening.

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