1981 KZ1000 J-to-K build

So when I was moving the crank to the new case, one of the piston slots is *really* tight, and I ended up snapping a ring. I was just going to buy a new set, but checking online they want around $100 just for the rings. Ouch. So I checked the other engine block which has been sitting outside under a blanket for the last two years... and surprisingly the rings weren't totally rusted out! Well cool, I popped rings off a couple pistons, and once I flip the motor back around I'll change out the broken ring and check for any other problems.

The weekend is almost here! I'm hoping to get the bottom end of the engine sealed up, hang it up on the frame, and maybe even get the jugs in place. Got some other things around the house that need worked on, so my time will be divided, but I really want to get back working on the bike again...

Well that was rather stupid of me... I only *thought* I was going to work on the engine this weekend. Turns out I could make more progress if I actually owned a friggin torque wrench!!! I have a 25-year-old dial type sitting on a shelf, and absolutely no faith that it is still calibrated. Found one at a car parts store on sale for $20 -- yeah I'm not going to buy a precision tool THAT cheap. Got a nicer one ordered off ebay, just have to wait for it to arrive.

In the meantime, its so hot outside that I don't even want to leave the house. It'll be cooling down by 10 degrees through the week, though, so maybe I'll find time to get something else done.

Hooray! Torque wrench arrived today! Looks like a good piece, and once I understood what I was feeling for, I tightened down the four bolts on the center crank. Have a lot to do this weekend, but I'll find some time to work on the engine and get some new pics.

Hey Shadow!

Congrats on the new torque wrench. It makes me wonder how we ever made it out of the dark ages without a good torque wrench? :laugh:
I have been in the same boat as you lately with the home-work commitments and the extreme heat that feels like it's trying to melt my shoes to the pavement by the time we get home from another day at the office. Should I go out in the garage and get to gettin' on those carburetors finally? (sideways glance at the thermometer )

Anyway. Hope your weekend goes well with engine assembly and your family doesn't find a melted puddle of bike builder on the garage floor by Sunday evening :laugh:

I finally figured out the right position for neutral on the shifter (hint: it's the spot that keys in half way through a gear change). I also read that it won't shift into 2nd unless you are actually rolling -- very cool feature! Great so after a bit of hesitation I was able to get the case halves together, found all the bolts and got them torqued down. After verifying everything still rolled smoothly and the transmission was shifting correctly, I put on the oil pan... and then disaster!

As I noted in my other thread, it turns out this oil pan does not match up with the oil filter cap I have, so the O-ring doesn't actually sit on the pan and would never seal up. These are the original pieces from PO, so somebody somewhere really screwed up. My only option is to take off the pan from the other motor, get it cleaned up and painted, and hope it also fits this case (it should, they're the same year). Just real frustrating that I was finally making some progress today and had to come to a grinding halt yet again.

It's August already. The way things are going, I've lost all faith that I'll have the bike running this year. At this point I'll just be happy if I can get the engine reassembled on the frame, then at least I can work on the wiring and electrical over the Winter.

I need to pick your brain for a minute. I know you have been working on this for a long time and hope your memory is better than mine lol. What temperature did you bake your painted pieces at ? What brand is the metal flake engine paint you used and where did you find it ?. Thanks and continue the great build. I'm doing a stock 1981J1 now. Were your exhaust valves very carboned up ? Mine were horrible and I am hoping they lap in ok. I found a product that I use in ALL my vehicles now as it removes Carbon in the head and frees up the rings. Check it out on you tube. There is a fishing charter captain video that shows a before and after oil change after using this stuff. It is expensive (about $27.00 for 12 ounces) but only used 1oz per 10 gallons. It cleaned up my Yamaha 1115 outboard and now it runs smooth as new with 625 hours on it. You don't have to use it every time you gas up either. Keep the blog coming and thanks for your help. jon

The cast-iron engine paint is by Duplicolor. I baked it at 225F for 1 hour. Some spots got a sandy look to them after baking, but a light wet-sanding with 1000-grit cleaned them up fairly well. For the pipes, VHT makes a 2000-degree cast-iron which I'm going to use.

I haven't actually touched the valves yet... that piece is sitting off to the side until I can get the main case put together with the jugs and mounted on the bike. I do know one of the exhaust valves has a brown spear across it, so I will likely try to re-lapp the valves just to make sure they have a good seal.

I have 2 of the Piston Ring compressors I bought from Piston Posse as they suggest doing 2 at a time. Not sure if I read that your cylinders are on yet. I can lend you these in the beginning of September is you need them. The engine paint you used was kind of a Metal flake. Is that the Duplicolor paint you are referring to ? It looks sharp. You are doing one heck of a job and I enjoy reading your posts. Please keep them coming. Thanks for your help.

Yeah the paint has a nice sparkle to it. It's an odd color, under house lights it doesn't really look like metal flake, but out in the sunshine you see it.

Nope don't have the jugs on yet, I'm going to do that after the case is mounted on the frame, and I have to get the other oil pan cleaned and painted before I can do that... so it'll be awhile yet.

You may want to think about adding the jugs before you install the case in the frame. I did watch a You tube video that showed one of the Technical Motorcycle schools mounting the cylinders to the pistons. The way they show it .... it is really a 2 (or 3) person job and I believe it requires more room than you may have if doing it while the case is mounted on the bike. Maybe I misunderstood your last post lol. I will try to find the link I watched on You Tube and post it for you. I just fimnished sand blasting my top end valve assembly. I thought I had everything taped up so no media would get in lol. I blasted it off very well with clean air EVERYWHERE there was a spot that sand could have been. Brought it home, rinsed very well with Brake cleaner, Blasted with air again and started removing the tape. What a mess .... another can of Brake cleaner, some paint came off and I was very surprised that even the oil port holes were plugged solid even with the tape covering them. As Elmer Fudd was fond of saying ... "BE VEWY VEWY CAWEFULL". Any thoughts or ideas you have would be appreciated. Sand blasting the block (which I did not take apart) and Jugs next week. When your ready I will send you the Piston Ring Compressors if you are interested. i think I may try the baking of the paint in my smoker instead of our oven. Hopefully our meat won't smell like paint. Thanks again. jon

Here is the link to the You Tube video that shows the installation using the Piston Ring compressors I puchased. I have to add that ... I don't mean to talk to you like you haven't done your research OR that you are an idiot lol. Please don't think that. You are helping me so much with my rebuild that I want to share any information I have or that I have found. Anyways, The Piston Ring compressors he is using in the video are the ones I have. There is a ton of good info in the video (if you haven't watched it 10 times like me). Below is the link.

I've been doing them two at a time for 40+ years.
Steve