Hello all,

So here is a little description of my issue with my Yl-1.

I have only ever worked with single speed or two speed automatic two-strokers in the past.

I apologize for the length of this post. I just want to be detailed.

Once I got her running I noticed that there was serious slipping when in 4th gear (4 speed bike). I left this be while I sorted other things out, Eventually I noticed an issue where I would be shifting into 4th and I would end up back in neutral, then when I would try and shift up again I would end up in 1st gear. About two weeks ago I rebuilt the clutch and eliminated the slipping in 4th gear, however now I have a more serious issue where I completely lose the ability to shift.. let me elaborate... I will be riding for about 20 minutes or so and then I will go to shift from 3rd to 4th and nothing happens. then I cannot shift at all, up or down, I will just be stuck in neutral.. no response from the shifting lever at all, no clickin in or out.. nothing... My only though is that it must have something to do with the tranny fuild I'm using, possibly something is happening when it gets heated up.. (10w-40 conventional for wet clutches). after it sits for a while I will be able to shift again...

Any advice would be GREATLY appreciated.

Thank you

Moved from the Bar to the classic section.

I would say that it was more to do with the shift mechanism than oil. Shift arm spring or an issue with the neutral stopper would be my guess.

Thanks, sorry for wrong section

No worries. Please see my answer above for my thoughts.

I don't have a workshop manual for your bike but a lot of these early Yam's had an adjuster screw which can be used to adjust the shift. It is by the gear shift arm.

Dirty is on the right track,,, shift pawl / return spring .etc. why you got ATF in box,,, put in correct SAE. it will help ,,,

Welcome bye the way...

Yeah there is a nut that is accessible from outside the case. I do recall this being related to the spring.. Should I just loosen it all the way and just turn it a bit at a time? Everything was very clean when i popped the clutch side open..

Return spring would make perfect sense.

I'll take a look at it after classes tonight.

If it is not a spring then look at number 4 in the first link. The numbers are hard to read so the part that fits to number 5.

LINKY

Second part of the shifter mechanism

LINKY

Full parts list

LINKY

Thanks DirtyDT I really appreciate all the info. I'll let you know what happens

ok here is an update. I took it out and rode around till the problem started. Then I proceeded to adjust the clutch to see if I could get any change... What I found was that if I adjusted the adjuster screw or the cable adjuster to anything but fully tight the clutch slipped when I started to ride. What I don't understand is how the rod that the shift armature is supposed to return to the original position, unlike the schematics you linked there is no visible return spring(or signs of one being absent) I will post pictures so that hopefully you can see the difference.

Also the adjuster screw and single ball bearing were in during testing( just out during picture) I am trying to understand how this all works from the schematics but i cant even find the rod in any of the schematics available

If you mean the clutch pushrod which is seen in your second photo just in front of the front sprocket this is shown under the clutch section in the parts list as number 8 Rod push (2). This relys on the springs number 22 pushing against the pressure plate number 21 to return the pushrod to the normal position when you let the clutch lever out.

O geez that makes so much sense... so that wouldn't have anything to do with my issue..

Basicly I have no choice but to split the case.