KZ1000ST Camshaft chain guide sprocket

Conti... I own a couple of STs and have gone through this. I have been buying cam chain bits off eBay over the years and so I made use of used parts except for the rubber dampeners and fingers and cam chain. If I wanted to buy new, I would check with www.z1enterprises.com as they may be able to sell you some of these bits from racing applications that might just be less than the Kaw bits.

The rubber on your upper idler sprocket is shot. It should be replaced. I wouldn't even measure the cam chain. I just replace them while things are opened up. You have some options.

First, you can remove all your side covers and split the cases. This costs you one gasket set and several hours labor scraping old gasket. The second option is to use a master link cam chain. I have used these over the years and have NEVER had one fail. The pressure on the staked pins would come from the side and there is little pressure under normal riding conditions. This saves you a few hours work scraping and you don't have to use a full gasket set to replace all the cover gaskets.

I have found that EVERY one of the rubber dampers in the front of the cylinder block has been cracked when removed from an engine and these are the worst designed of all the cam chain bits. I replace this bit on every engine I open up. I replace the cam chain. There are four rubber pads under the tower on top. These must be replaced as they harden and will suddenly just crack and drop down onto the crank. The big rubber roller that is in the middle and under the cylinder block... haven't seen one of these goes bad even if chewed up a bit. If any of the sprockets have questionable rubber, replace them. I am not sure but I think Liska racing parts might be available and z1enterprises.com may have them... not sure but they are sturdier than stock and less expensive. As far as the tower, you really can use any from any 73-80 if you have an ST. There is more room under the valve cover than on earlier models which will work nicely. You can't go the other way and use the bigger ST tower on a non-smog head bike (like a Z1/KZ900 or early KZ1000) as the tower just doesn't fit under the valve cover. When you buy your chain, get one with 124 teeth... MOST of the chains are for non-MK II type engines and they have less teeth on the crank sprocket and need 122 link chains.

Thanks. I opened the motor on the last WE, and I had a closer look at the tensionners. Surprisingly, they aren't in a bad shape:



But the upper sprocket definitely needs to be changed:


I haven't look at the roller in the middle of the engine for the moment.

Unfortunately, I'll have to open the motor entirely. One of the small bits of rubber, which are over the rollers guide, "disappeared". I don't know where it is, and I fear it's now inside the motor. That sucks. My fault ! :silly:

Conti wrote:

Thanks. I opened the motor on the last WE, and I had a closer look at the tensionners. Surprisingly, they aren't in a bad shape:....

Even your "worse-for-wear" component _still_ looks a lot healthier than the cat.:woohoo: