Why are cam chains for J-motors so hard to come by?

About the only camchain I have not been able to find on the internet is one for my J-series engine. Why is that?

They used that chain all the way from 1981-up. 20 yrs + on the police KZ1000. You can't simply order one?

Oh-yes you can get them from Kawasaki for about $100, but i noticed that for all of the other bikes you can buy aftermarket chains from anywhere around $40 to $60. i was just wondering why there are no afermarket CHEEP chains available. Hay after all I am a Cheep Bohemian and am always looking for deals:blush: .

Z1E

link

The J-motors use a Hi-Vo (stands for High Velocity, developed by Morse, a division of Borg Warner, originally seen in the 1966 Olds Toronado)(and, come to think of it, properly spelled Hy-Vo, when actually made by BW/MORSE) which is different from z1/kz motors.
this is a standard cam chain

this is a Hy-Vo

Notice that the Hy-Vo doesn't have a single set of sideplates, but rather is mostly made up of "sideplates". It's much stronger, doesn't stretch nearly as much, and runs quieter. This last is why it's often refered to as a Hy-Vo silent chain. The link that's provided for a master link is also not right. I know Z1 sells a master link, but these chains are meant to be endless. Which means that, not only are they more expensive, but that to change one properly you need to split the cases. :blink:
So, are you SURE you need to change the cam chain?
Oh, BTW, my (limited) experience is that the chain doesn't wear out nearly as fast as the plastic guide blocks.
front cam chain tensioner
rear one
THere's one that fits into the cam cover, as well, but I don't see it on Z1's website. Call them, 'cause that's where I got my new one.

Are the J Motors much better than the z motors? I thought I read somewhere that they had much trouble with the rings and burning oil. I heard also that they crank and have a much better head design than z motors. But then someone told me they were junk. What gives? The timing chain looks solid. Jim at redline said the later kaw motors were much better than the early model z1 motors.

saxjonz wrote:

Are the J Motors much better than the z motors? I thought I read somewhere that they had much trouble with the rings and burning oil. I heard also that they crank and have a much better head design than z motors. But then someone told me they were junk. What gives? The timing chain looks solid. Jim at redline said the later kaw motors were much better than the early model z1 motors.

Well, considering they were in production for 25 years or so (1981-2005) they must not be too bad.

There isn't a huge difference actually. The better hyvo cam chain was sort of offset by junky cam chain rolling bits but otherwise, there isn't much difference. A little larger valves would be the biggest difference. As far as oil eating? They are air cooled and the cylinder bore to piston clearance is pretty big as a result. This means that when you get some wear, blow-by is the result. This is pretty much like any air cooled engine. They just don't go as far between rebuilds as a water cooled engine but rebuilding is simpler because there is no plumbing or water jackets in the engine.

steell wrote:

saxjonz wrote:

Are the J Motors much better than the z motors? I thought I read somewhere that they had much trouble with the rings and burning oil. I heard also that they crank and have a much better head design than z motors. But then someone told me they were junk. What gives? The timing chain looks solid. Jim at redline said the later kaw motors were much better than the early model z1 motors.

Well, considering they were in production for 25 years or so (1981-2005) they must not be too bad.

Well, that is good. I just heard that these bikes had problems from the get go before the warranties would expire they had problems with smoking, etc. I would have to pull up the article I read. I think it was something to do with the production quality and not putting out engines to the tolerances specified. That's all.
I don't believe all that I read but you guys know more than I do as you all rebuild engines and carbs for sure would know about the ins and outs. All I have to say is that I wouldn't ride any older bike unless it was a Kaw or my dad's bmw he had. My dad bought a 750 honda when they came out. I remember him saying what a pita it was that every time he would take it on a long ride he would have to tighten all the bolts down.

Originally, there were problems with the J series Kaws. I was a dealership mechanic when they came out and worked on many of them fixing problems under warranty.

Twisting cranks, crankshaft thrust bearing faliures, porous cylinder blocks, head gaskets, cam chain tensioners, were common problems.

The 83GPz11 was the first factory hop up to the J series but evene then, crankshafts were a problem.

Compared to a KZ engine, the J was a bit of a disapointment in the reliability category. The factory fitted several different grinds of camshafts to the base package to taylor the engine for different models. For example, the LTD & CSR models had less duration than the standard J. GPz

There were a number of significant changes from the KZ that included larger valves, larger ports, CV carbs, etc. etc. etc.

They are still a good engine though and capable of producing very good power when setup properly. Just like the KZ engine, they fit a wide variety of applications and there are still parts available for them.

A very good engine for a project bike. Well worth restoring but like all things from the past, you need to have a passion for them because they are old and rebuilding them takes significantly more money than it once did....

Larry C





saxjonz wrote:

steell wrote:

saxjonz wrote:

Are the J Motors much better than the z motors? I thought I read somewhere that they had much trouble with the rings and burning oil. I heard also that they crank and have a much better head design than z motors. But then someone told me they were junk. What gives? The timing chain looks solid. Jim at redline said the later kaw motors were much better than the early model z1 motors.

Well, considering they were in production for 25 years or so (1981-2005) they must not be too bad.

Well, that is good. I just heard that these bikes had problems from the get go before the warranties would expire they had problems with smoking, etc. I would have to pull up the article I read. I think it was something to do with the production quality and not putting out engines to the tolerances specified. That's all.
I don't believe all that I read but you guys know more than I do as you all rebuild engines and carbs for sure would know about the ins and outs. All I have to say is that I wouldn't ride any older bike unless it was a Kaw or my dad's bmw he had. My dad bought a 750 honda when they came out. I remember him saying what a pita it was that every time he would take it on a long ride he would have to tighten all the bolts down.

One of the problems that the police depts had with them was pounding the base gaskets out. We had Cometic make some that seemed to help the problem.

Jay