Shifting issues

Bike : 1974 Z1 900

I posted a question about this last year and thought I had figured out the problem, but I went for a short ride today and found out I had not.

Recap : The bike is had to get past 3rd gear and when I can get it into 4th or 5th its then next to impossible to down shift into 3rd and so on. It feels like the shift lever is hitting something.

What I have tried : I replaced the clutch cable and adjusted it by the book. I made sure the shift lever was not hitting. The issue remained

Question : Does this sound like clutch problems or transmission problems. The cluch adjustment is almost gone, so I have considered replacing the clutch. I don't want to tear the bike down if I dont have to. Is there a way to know what the issue is without surgery?

Any idea would be much appreciated.

dumb question, are you using the clutch when you shift?

I'm pulling the cluch lever, but I'm not sure its doing its job correctly. Thats kinda what I'm trying to figure out (Clutch problem or transmission problem).

about the only time I use the clutch is when I take off, I was trying to figure out if the clutch was not working or if the trans was not letting it shift

I was checking out some other clutch related threads and found a common issue. My clutch starts to catch when the lever is almost all the way out. I adjusted the cable by the book but that is where it catches no mater what I have done. If the clutch is out of adjustment would it cause the bike to have problems shifting? If the clutch is worn out would it cause the shifting issues? I have heard of worn clutches slipping but not hard shifting.

I wonder about the clutch rod, maybe bent?

I was thinking the same thing, so I tore into it today. When I did I found the shift lever return spring was bent. It must have been weak last year when the problem started and now it is gone. I have ordered a new spring and hope the problem will be resolved once it is installed. I hate having a bike running well for once and not being able to ride, but what can you do?

Follow up: I received the new shift lever return spring and installed it. The spring fits very tightly around the post it goes on. It fits so tightly the spring can only touch the limiting post on one side. Does anyone know if this is normal? Shouldn't the spring touch both sides of the post when the shile lever is centered? I ask because while improved the sifting is still not right.

Which spring are you referring to? Are you talking about the large spring coil with the two arms that goes over the shift shaft? Keep in mind there are TWO different parts that look almost the same. The one part is for the Z1/KZ900 and the other is for the KZ1000. The 903cc spring has THREE loops and the 1015cc spring has FOUR loops. The spring with four loops WILL NOT allow things to be spaced right and as I recall the pawls will drag on the shift drum if you can get it installed.

I have the 3 loop version of the spring. The problem I believe is that the arms of the spring are being forced apart by the post its mounted on. Since the arms are forced apart the shift lever is not being returned to its correct position between shifts. This is my theory anyway.

I included a pic that I hope illustrates what I'm talking about.

home.earthlink.net/~bryanharper/Pics/spring.bmp

The left image is what I have and the right image I think is what I want.:dry:

Post edited by: bharper6649, at: 2007/03/21 13:26

Not sure what to make of this. I am pretty familiar with the external shift mechanism and don't see how you got the spring's two legs open like that. To install, you have to sort of pry the legs apart since they cross and they should have pretty good pressure on the locating peg like the image of the one that has both legs touching the peg. I have tried to use a 4 loop spring in the past on a 903 engine and it spaces out the shift pawls a tad too far and they don't work right. If the spring that brings the pawls together is shot, the pawls won't work right and it won't shift. If the detent spring is shot, you will have a hard time shifting. The detent is the little banana shaped deal up in the top left that has a spring connected to make sure it returns. Do you have any way of actually taking a real picture of the stuff under the countershaft cover? Take a pic of the shift drum while the bike is in neutral. Take a pic of the top left and of course, the external shifter if you can as well. I bet it ain't that big a thing that is keeping you off the road.

I will take some pics the next time I tear into it. I can deal with the shifting glitch until the next rainy day. When I put it back together the last time I checked the shifting properties after each step. When I started the shift linkage worked fine. The spring touched both sides of the post and returned the lever to center. When I put on the cover it must have pushed the shift lever back causing the spring to open up. I'm not sure why this is a problem now. I compared the new sping to the old one and minus the broken arm its identical. I'm going to go ride and see how it goes.

Thanks