Kz900 Engine casing crack after slight explosion. No clutch activity now.

Hey every one! I'm so glad to join your forum. It seems to have a wealth of information.It just pains me to have to post something like this as my first post though... So 4 days ago I purchased a 1976 Kz900ltd. Bought it in great condition. Seriously the best bike I've ever been on. Well any how I was out riding yesterday when I pulled in the clutch to switch gears when the cable went really slack. The cable didnt break it just went really slack. Actually prior the clutch was really stiff. I should have adjusted it, but I thought I'd grow acusstomed. I couldnt change gears with the engine running, the gears would just grind. Anyhow after a bit of checking around I found if I pulled the cable with my hand I could pull up the slack and get the bike in gear. I only needed to ride the bike a few blocks to a bike shop. Any how after I secured the cable to the handle bar to keep off the slack, I got er moving. I couldnt fully engage the clutch though and even when pulled all the way in it crept forward. So after riding for about two minutes I hear a loud bang and I stop moving. The clutch is completly slack and the bikes in a false neutral, the motor was still running though. I pull over to the side of the road look down on the left side of the bike around the shifter and I see it. The casing around the shifter has seemed to "exploded" and theres a huge crack in it!! I have no idea what happened. The metal casing was broken cleanly in half! Now nothing works. The electric starter does nothing. The kick start is loose and shows no sign of compression. I have no idea what happened. I can see in the casing now and when I pull the clutch in I see where the pad thats connected to it would make contact to another component, but they no longer touch. Ok so please guys tell me how bad this is. Can the case be welded back together? Is there internal damage? Is this gonna cost an arm and a leg to correct.Please dont let this be a lost case. I just purchased it and as I said, its seriously the best bike I've ever been on. I'll post pictures in a little while.

You can replace the clutch cover(Ebay). Is the sprocket casing intact? As far as the kick starter, bike could be still in gear, since the clutch is not engaging.

This should be a easy and non-costly fix. What might cost is replacing clutches and steel plates, but I would check them anyway. The pad that pushes the rod is connected to a ball bearing that engages the clutch.

But all said, it still would be worth fixing it right to enjoy your ride.

I am wondering if the sprocket came off and somehow got wedged in and broke the cover along with the cable breaking

This is odd, indeed. the case around the shifter, covers the chain and sprocket,so 1 would think u broke the chain, wich then hit, and broke the cover? u should pull the cover and tell us what u see.
maybe the stator came off,and the starter gear is off as well (they are attatched together)?

Hey all. I thank you all for your respones. I'm hoping I can get this resolved soon. So I went back to where the bike is stranded to get pics of the damage: <img src=”http://s282.photobucket.com/albums/kk264/nahman19/?action=view&current=P1040139.jpg ”>

<img src=" s282.photobucket.com/albums/kk264/nahman...current=P1040149.jpg ">


<img src=" s282.photobucket.com/albums/kk264/nahman...current=P1040155.jpg ">

I'm going to try and go back tomorrow and remove the case to look inside. Not really very handy but want to be. And I dont really have many tools. If you guys would be so kind as to tell me what size wrench is needed to remove these nuts, id appreciate it. So can that be welded back together or is a new one a must?

I think my files were too big...i'm going to resize them. Also, is this the right casing?:


cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll...m=&item=180277161778

doesnt look too different...

lets try to post these photos again:

Same cover, but you need to remove the cover to see what damage
might have taken place inside, I'm curious!!!. You might have to
replace the sprocket housing as well. 10mm socket wrench will work, and allen wrenches (metric). You might have to remove the footpegs to remove the cover.

Nahman, from your pictures, it looks like this bike has been upgraded to aftermarket Hex/Allen head bolts... at least in some locations. That's good news as these are generally more durable and easier to work with.

Mine are Metric 5 mm so you will want to have the correct 5 mm socket for your ratchet, or a 5 mm T-handle tool or an old fashion/cheap 5 mm key. Personally, I prefer and use a good quality T-handle.

I concur with others here, so far your pictures suggest a simple cover replacement. You will only know the full extent of the damage once you remove the existing cover. If no structural damage has been done to the main engine cases or to the sprocket drive shaft then it's a pretty straight forward/cheap fix. This is your cover:



All the diagrams for your "1976 900 LTD" can be found at the Kawasaki site. See here:


www.kawasaki.com/DefaultFrame.aspx?strCo.../VICHOOSEVEHICLE.ASP


If the main engine cases have a problem... well we'll cross that bridge when and if we get to it. :huh: The fact that you have not reported seeing engine oil loss from the engine is encouraging.

Best of success.

PS
Can you add your year, model and location to your signature to get the best responses... and it's considered real friendly too.

Look at the chain in the above photo.

I only see one one line of chain when there should be two, and it's hanging down, so unless you have disconnected the chain, I'd say it's broken, or possibly the sprocket has come off.

Just going to have to remove that cover and find out what happened.

You're definitely going to need another cover

Is the stock chain guard fitted?

The cracked piece in the pictures is the outer countershaft cover. On a KZ900, there is an inner cover plus a guard piece over the countershaft sprocket. Many are missing. I suspect that the countershaft sprocket 27mm nut came loose but the chain may also have broken. The reason you have hex bolts at the top two positions on the cover is that these are 110mm long and most bolt kits don't include them. Take off this cover and see if there was damage and what caused the damage below. When you find a new cover, also buy some new socket head stainless bolts (in kit form) from www.z1enterprises.com as the rusty zinc bolts look bad. The countershaft sprocket should be installed with a locking washer (get a new one from Z1E as well). If the chain broke, replace the chain and both sprockets.