1980 B2 Rebuild

Hey all, trying to fix a few things on my new to me 1980 KZ1300 B2 which I posted about having some compression issues here . Overall my goals for this initial teardown are just get the thing running. There are a TON of super helpful posts here about maintaining this bike and I’m hoping to get in on some of the action :)I additionally got a really good deal on a Creality Otter on eBay and would like to make 3d scans of all parts I am able to. I don’t really have any experience with scanning or CAD, but this seems like a great way to get in to it. Anyone who is interested in a particular part being scanned, let me know and I’ll try to get scans out sooner for those items.
 Goals:- Full engine rebuild
   - Cam chain tensioner upgrade
   - Tensioner sprocket & roller replacement
- Water pump stuff
- Repaint with Cerakote
- Front end/seat A-series swapFuture Goals:
- EFI conversion (Megasquirt)
- Front triple/fork swap (modern stuff)
- Modern calipers/brakes ##Day 1So far I have been able to remove all of the touring related features and am looking to try converting to an A-style. Unfortunately it slipped my mind to take a before picture.After removing a handful of bolts securing the cams and cylinder head, I was hit with a strong smell of bad gas. While the coolant (neon green) and new oil I removed seemed in good condition, I’m hoping this isn’t indicative of other problems I will run into down the line. Additionally, there was a small ~3x1mm metal shard I found near cylinder 1’s exhaust valve, and a few spots that look like they were chipped. Seems like someone has definitely been in here before. So far, everything else looks to be in good condition.I’m hoping to have the block removed next time I work on this and be able to figure out what is causing the compression issues.

Looking forward to watching you build this one out.  Sounds very similar to whaat I'm doing . Start with a B and convert it to an A plus fix all the inherent issues and upgrade to current standards.Sounds like you are a builder. This is the fun stuff. Kudos !!

##Day 2

Cylinder head has been removed with a bit of heat.
- The gasket is stuck on there pretty good and seems to be original.
- Pistons are caked in carbon, but the walls seem to be in okay condition. They are all slightly tilted and I'm able to see a bit of the ring on the intake side on all of them. Also a bit of rust around the top of the sleeve.
- At least a few of the valves seem to be slightly off center (I'm assuming slightly bent). Good thing I came across a full set on eBay last year!
- Buckets don't seem to have any scoring and be in good condition.

There was a nylon gear at the top that was magically missing about half the teeth.... Seems like I have seen something about this before on here...

I remember seeing something somewhere about needing to adhere to the break in process for these older bikes because it could cause the cylinders to become oval shaped. Am I going to need to look for oversized pistons and rehone?

Goal for next time will be to get the block removed and see how the rods and lower items are looking. I have been disassembling the engine while it is installed due to how difficult it seems like it would be to take the whole thing out in one go. I was woried I wouldn't have enough clearance, but while a bit tight has not been an issue.

In for a penny, in for a pound .  Liska racing kz1300 cam chain tensioning sprocket   would be my reccomendation. Many have them on their bikes and are happy. They will make a whirring noise for the first rew hundred miles and then quiet down. $95 USD.
As  far as the cylinder- only a dial bore gauge and a 2-3 outside mic will determine if you can get away with a good honing and new rings. These cylinders wear like iron. Scotch just did a rebuild with some crazy miles on the bike and got away with a hone and rings.

Scotch just did a rebuild with some crazy miles on the bike and got away with a hone and rings.

87,000K actually.  I took the cyl. and head to a trusted machine shop because I didn't have the gauges and micrometers required. Everything was well within spec so they did a "Precision Hone" and I have never regretted that for a second!
Something to seriously consider: Page 2

www.kz1300.com/forum/engines/4099-engine-rebuild





 

87,000K actually.  I took the cyl. and head to a trusted machine shop because I didn't have the gauges and micrometers required. Everything was well within spec so they did a "Precision Hone" and I have never regretted that for a second!

Wow, 87k is quite a few miles! Gives me quite a bit of hope for the condition of my cylinders since mine only has ~27k. They did seem to have a bit of the factory crosshatch still, so I might not have to get much work done for that. I'm not sure of anywhere in my area of Missouri that does this, but I'll have to take a look around. I'm hoping I won't have to ship it out since that seems like it will end up being expensive...

##Day 4

I was able to mostly remove the engine block (I feel like I'm using the wrong term here), and as noted above, the cylinders seem to be in good condition other than a ~2mm ring of rust/grime at the top of all 6. I can't seem to get the whole thing off because the cam chain runs over part of the water pump drive. There was a piece I could use an 12mm wrench on in the left side and a bolt behind the pickup coils, but I was unable to break it free and the part I had my wrench on seems to be slightly stripped now as the wrench has a bit of slop. Lots of heat and penetrating oil didn't seem to help (Page 76 of manual). Timing chain came off fine, although I ended up dropping it into the engine with the gear.

I'm seeing that it is more of less always worth getting new piston rings. Are these any good or is there somewhere else that is reccomended:  imdpistons.com/products/kawasaki-zn1300-...r-piston-ring-sets-6

Next time:
- Fully remove block
- Remove and inspect pistons