KZ650 Sleeper Build (KZ1000 engine transplant)

Going to be getting back on this build soon but the window to ride here is gone for the season.

The carbs got flushed out so I am ahead of the "winterizing" game. I do need to drain the oil for the stator removal, its on the center stand and don't have room to tip it over where its parked.

 

Stator swap out won't be taxing, but I dislike dealing with that black RTV.

l was also thinking about going back to stock cam end plugs as the RTV I redid on those is leaking at one corner again. No risk on blowout as the cam cover has a good size vent. 
Either I go back to stock or I buy the billet plugs with the O rings as I don't like dealing with the oil weeps.

The other winter project on tap is milling a billet center top idler bracket to aid in cam cover removal. Along with that a billet center idler sprocket.

And again:   Congrats, nice and very clean machine, very good job, you´ve done on it !!! Double thumbs up !!!

MFP-Joe wrote:

And again:   Congrats, nice and very clean machine, very good job, you´ve done on it !!! Double thumbs up !!!


 

Thanks.

I've got the engine in the frame and running, but have not ripped down the street yet

Maybe I was overly cautious, should have at least taken it around the block when the weather was half decent, but now its 10C here and rains most days.

I have had charging issues in the past and when I had trouble starting it in my garage I took pause. I would hate to be a few clicks from the house and have to push it back been there so many times in the past.
 

I just finished up the CAD model for the billet idler bracket.

 

 

I need to check a few sizes between the stock bracket and the cam cover to see how much clearance there is when they are assembled. Its just a matter of taking a loose cover and putting the idler in it. Its not something you can measure with a vernier, but I can do it with a feeler gauge set. I am using the cover and idler from my drag bike.

I needed to chop .16" off the stock idler bracket to remove the cam cover to the side, so I designed the new bracket .18" lower.

Once I check the clearances then I can make a machining drawing with sizes.
 

Today I checked the clearance between the cam cover casting and the stock steel 1000 center idler bracket.  There is tons of room side to side when the bracket was inserted to the depth it would sit with the stock rubber underneath it. I was thinking it may have had about .040" clearance on both sides (feeler gauge set) but it had tons, so much in fact that the whole feeler gauge including the frame slid in next to the steel bracket.
 

That feeler gauge is .270" thick, and it was loose. I adjusted my design to give .13" clearance per side on the top thickness. I also measured where they made indents for the center pin on the casting (just the top quarter of the pin)

 

I adjusted the nut till it went tight on the casting then slipped it out to measure the length. Both of these measurements are not very scientific but they are the best I can do and I am using at least .020" less on each measurement just in case.

I have now finalized the CAD model then started to make a dimension drawing and a itemized machining operations list. This is much quicker for me and avoids mistakes.
 

I have a couple of loose idle sprockets without the 7/16" center shafts (1/4"ID) that I need to use in this billet bracket I am going to fabricate. The center shaft is hardened and ground (for use with needle bearing) I could have tried to make that part but most material/heat treat options were too expensive.

Since that part number is NLA from Kawasaki I went on Ebay and found the cheapest option I could. I ended up paying $27 Canadian (delivered) for 6 pieces, they do have some surface rust from sitting on the shelf but I should be able to clean them up.

 

So for $4.50 each I had to take a chance on them. They are coming up from the USA so not sure if they will get flagged at the border for tariffs, so I will just wait and see.
 

This has been a great thread to follow. I am looking forward to seeing the billet cam chain roller!  

It might be a few days before I can get back onto it because I got roped into fixing a snowblower!

I got that blower fixed over the weekend so after putting away some tools and cleaning up I got back on this project. 

I started by squaring up the 6061 material I bought to make the idler bracket.  I also turned the rubber off the outside of the idler sprocket I am going to use on it. 

The inside rubber is still in very good shape, but I took the rubber that the chain rides on off for clearance purposes so I could design the bracket "thicker". I probably won't replace the center on this sprocket just yet.

 

I also modified a 1/4" hex bolt so it will clear the cam cover. I went with 1/4" because a M6 was sort of sloppy in the stock steel center pin. The bolt has a mechanical lock nut that has been ground thin (so was bolt hex head) Once assembled I may even weld the nut to the bolt.
 

Hey Injected, how old are those rubber damped sprockets?  Apparently the rubber degrades over time, even in the oily enclosed environment.  Granted my idler sprockets are 44 years old (they were replaced when Harry's Machine built the motor in 1981) but one had completely separated at the rubber (the bearing was binding) and the other wasn't much better.  I replaced them with Liska billet ones with the bearing but no rubber damper.  They're a little noisier but I consider it a healthy noise.  Those old parts were a bomb just waiting to destroy my motor!  Just my 2 cents and some food for thought while you've got the motor opened up.  

sf4t7 wrote:

Hey Injected, how old are those rubber damped sprockets?  Apparently the rubber degrades over time, even in the oily enclosed environment.  Granted my idler sprockets are 44 years old (they were replaced when Harry's Machine built the motor in 1981) but one had completely separated at the rubber (the bearing was binding) and the other wasn't much better.  I replaced them with Liska billet ones with the bearing but no rubber damper.  They're a little noisier but I consider it a healthy noise.  Those old parts were a bomb just waiting to destroy my motor!  Just my 2 cents and some food for thought while you've got the motor opened up.  
 

That is a original sprocket from a low mileage (~10K miles) '78 KZ650. I know I should really take it apart and make a aluminum center for it but for the moment I want to use it to prove out the bracket fit/function.

I am pretty sure I can find other idler sprockets around here that are worse off as far as wear to rebuild. What I need to do is to find and do a batch, that is more efficient than just doing one. Unfortunately a lot of my spare parts are in storage and its a bitch to dig them out, this one was sitting on top of my office desk

For now I am not too worried about it as I know the cam cover on this bike is going to be off several times in the Spring once I get the engine fired up again. In the Spring I will look at doing some and get it swapped out.
 

Before I start machining the aluminum I updated the design to put a radius in the bottom corners to strengthen it a bit. I also put rads on the mount flange corners. 

 

A few extra steps to machine but they will make for a better component.