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It's not much, there's a motor on the bike frame again! Dinged the paint a little, despite using a blanket, but I guess this gives me a chance to see what it takes to do touch-ups.



The camera flash made the cast iron color look lighter than it really is. Eventually I'll get some pics with the bike in full sun so the color shows naturally.

Another major accomplishment today... the bike is back over beside the garage and out of the back yard. I bet my wife is happy. I'll certainly appreciate not having to move it around every time I mow.

Did you disassemble the rear shocks and if so how do they come apart ? I sent you a private message about splitting the engine cases also. I did not want to take up your whole forum with stupid questions. Thanks for sharing.

I was going to reply to your private message, but as I was typing this out I realized there's a lot of good info here that I really wish I'd had a few months ago when I started pulling my case apart, so I'm just going to put it out here in public in case anyone else can also use the info...

Regarding the shocks, no, I didn't even know they come apart. I have a couple sets, so I just picked the ones that felt the stiffest and put them back on the bike... although some day I might get some nice progressives to replace them.

Start with putting the transmission in neutral... you'll want to note the position of things once the case is split. Also check for bolts on both the top and bottom of the case before you start trying to split them.

Really it's not hard, but if the case halves have a good seal that it takes a bit to get them started. It's about the same with getting the oil pan off, you just have to find a corner where you can start pulling the pieces apart without damaging the outer fins or anything else. If your case has the original paper gasket, it gives you a little space to get in there with a fine flat blade. I think I basically started going around the outside of the case, finding offset fins to pry against or other pieces where I could get some leverage, and just kept working it slowly until one of the corners finally started coming loose. Once you get a small gap started then it gets a lot easier to work from there, getting a flat putty knife between the gap to apply a little more leverage. The main thing to always keep in mind is to not apply pressure in such a way that it might damage the mating surfaces.

Once you get the oil pan off, take out the oil pump. When the case halves come apart, keep the case upside-down, and there are four bolts on the center crank cap to remove. Then you can lift out the whole crank (you may need the ring compressor on the outer two pistons). There are positioning pins in some of the bearing, so watch out for those when you remove the crank. Take them all out, because as you clean the case they'll end up falling out anyway.

There are two rods of gears for the transmission. Note that beside the shifter rod there is a disc with a black center, and there should be a notch or painted mark around one edge. You'll want to record the position of that mark so you can put the tranny back in neutral when you reassemble. (The position shown in my manual was off by about 30 degrees, so I had to find it myself.) There are three forks sitting in slots between the gears, two on one rod and one fork on the other. With the transmission in neutral, you should be able to freely spin the output shaft where the chain sprocket goes. Each of the forks has a pin that sits in slots inside the larger center bar. Just look over how things fit together, or take pictures if needed. At this point you can lift out those two clusters of gears from the case. Each of these has what looks like half of a piston ring that fits a slot in the bearings and the top half of the case -- again remove these and set aside or they'll fall out while cleaning.

There are also centering pins between the cases, one in front and one at the rear, and more of these pins around the sides. Some will be loose and others stuck tight. I would highly suggest taking pictures of all the locations where you have these pins so you can get them all back in later. There are different sizes, but they are interchangeable within the same diameters, however one side has a square shoulder and one side is rounded. When you put them back together, the rounded side should be out.

Another thing to watch for, there are one or two black plastic washers between some of the oil passages that run between the case halves. Otherwise you should be done now. You may decide to pull apart the mechanism from the outside of the case that handles gear changes. I pulled mine apart, but I had another unit sitting beside me to reference for putting it all back together again. I wouldn't do it again unless I really had to.

At this point I hit the case halves with some engine degreaser, let it sit, then hosed it down. Then use a putty knife to scrape off the obvious thick layers of grease, and hit it with the degreaser again. I find that with the lower power of my sandblaster, the sand just bounces off these grease layers, so it saves me a lot of time by getting down to bare metal manually.

After you finish painting and baking the pieces, you want to take them outside and hose them down. Spray water into every last channel, nook, and cranny you can find. Sand will be everywhere, and you don't want to leave anything behind. Don't forget to pull off the cap on the side of the case that covers a big oil passage. When you think you have everything clean, spray it down again. I kept going on each piece until I didn't see a single grain of sand coming out of any spots. Shake the pieces dry, blow out water with an air compressor if you have one, then let them sit for at least another day or two before you start putting them back together. You don't want to have any water left inside the case when you add the oil.

Now you're ready to put all the centering pins back into their holes, replace the internal oil passage seals, drop in the pins for the crank and the half-round rings for the transmission bearings. Put the crankshaft back in place, again using ring compressors on the outside two pistons as needed (I tried to wedge mine through without compressors and broke a ring in the process). There is an arrow on the center crank cap that should point towards the front. Make sure you torque down these bolts in order of the numbers marked on the cap... if you forget to torque them, you'll never be able to get to them without splitting your case again! After that, drop the transmission gears back in place, making sure the gears are in their neutral position. All of your surfaces should be oil-free, but if you're using a liquid gasket you'll want to prep the mating surfaces with some 220 sandpaper, very lightly scoring the surfaces without rounding them off. This gives something for the liquid gasket to bite in to. Before actually applying the gasket, you should practice placing the case back together and fitting the forks back into their slots. With everything together you can shift between 1st and neutral, but you have to give the output shaft a good spin to shift up into second gear. Make sure you can shift through the whole range smoothly (keeping in mind there is no oil in there right now so it will be a bit stiff). Once you have verified everything is working properly, put it back in neutral and remove the bottom half. You're now ready to apply your gasket and do the final assembly. Keep your liquid gasket sealer very thin, once finished it will be paper thin but you want to apply enough that it fully covers the surfaces once it squishes out.

At this point you're going to have a pile of several different lengths of bolts for your case halves. The trick to remember (and this has been true of every engine I've worked on) is that when you drop the bolts into the holes, they will ALL be sticking out the same amount regardless of their actual length. For the case halves, they were all sticking up about half an inch. Note that there are a couple bolts on the case where you want to apply more liquid gasket sealer underneath the head (check your manual). Tighten down the bolts loosely by hand, then work them down to full torque in a couple steps. DO NOT OVER-TIGHTEN! These bolts require very little force to reach torque. For mine, it was only 90 inch-pounds or 7.5 foot pounds. I can easily double that by hand, so don't go crazy when you initially seat them.

The oil pan will be the same process. Get the oil pump put back in and torqued, put in the large O-ring around the oil filter hole, and get your gasket in place. Again you will have bolts of various lengths, but they all stick up the same amount when sitting in the correct holes. Torque them down in multiple steps, then let everything sit overnight so the gasket sealer dries. Finish off your oil plug and oil filter assembly, and you're ready to flip the engine back right side up.

Hope that helps, let me know if you need more details about anything...

Thank you so much for the info. Unlike your weather, I am waiting for it to cool down to start the sand blasting and painting. I have not broken into the case yet and your reply was very helpful. Actually I was waiting for your reply before I started tearing the engine apart lol. I have sand blasted the valve train and have the cylinders off but was kind of hesitant to split the case. I was originally going to tape everything up and blast it WITHOUT splitting the case but after seeing where the media ended up on the top end after taping, here I go lol. I would Like to tell you that the rear shocks "according to my manual" cannot be taken apart. I'm not sure I believe that but will let you know as soon as I find out, hopefully without any damage to me or the parts. What liquid gasket did you use on the case ? Thank you again. jon

Honestly I would NOT try to take apart the rear shocks. Stuff like that is frequently a press-fit one-shot deal and I don't think I would trust its safety if there wasn't a clear intended path for end-users to disassemble it.

As for the gasket material, see this thread, we had a bit of a discussion on the subject after I had already assembled mine, so I'm taking a chance and seeing if my brand holds up. Since you haven't even cracked yours yet, go with the recommended threebond.
kzrider.com/forum/2-engine/603471-complete-gasket-set

Some small progress so far this weekend... Got in the new seal and got the cover plate over the gear change mechanism. Got in the last motor mount bolt and got the airbox back in place with the new rubber elbow to the oil breather. Spent the rest of today working on the valve head. Man what a lot of carbon build-up around the valves and inside the exhaust ports! I think it's a good bet this was why there was some sign of exhaust valve leakage, but because of the sandblasting I still need to pull out the valves for complete clean-up, so I might as well lapp them anyway.

So I have all the carbon cleaned out, the oil and grease has been fairly well removed, and the thickest layers of build-up have been scraped down. I spent a couple hours with the sandblaster so far cleaning the top and bottom, but tomorrow I'll try to get into the fins along the sides. Not planning on painting it this weekend, but hopefully can get it mostly cleaned up tomorrow and try to get the valves out.

Made up my own little tool and popped out the valves today. I was expecting an E-clip, so the first one took a bit to figure out the clamshell pieces. Overall the valves look good, but there is definitely some carbon build-up on the seats, so definitely need to grab a lapping kit. Maybe while I'm at the parts store I can find something that will remove all the carbon.

The head itself is actually pretty close to done. Most of the surface area is clean, but there's some stubborn spots where the grease got baked on. The brake cleaner isn't removing the rest, so I just have to work it down with the sandblaster. I can probably finish cleaning and lapping in a day, then lay down some tape and get it painted. Then I just have to do some reading on getting the chain and cams back in alignment.

Still only had one afternoon to work on the head again this weekend, and I think I need at least another day to finish it. Got more of the larger bits of carbon loose today, and the valve seats look pretty shiny now. Should be ready to do the lapping, when I get a chance.

I spent most of the day sandblasting. Got the other left cover (I think this covers the alternator?) cleaned up and painted. I started cleaning one cover, then realized it was the one from the original engine where the intermediate starter gear had torn out of the hole, so I grabbed the other one and started working on it. One odd thing I found, someone had screwed in about 1/4 inch of heli-coil in one of the mounting holes. No idea why, that it a through-hole for a bolt to pass through, but they hadn't drilled out the mounting hole so everything looks fine on it. I'll get one of the wire coils cleaned up and put back into the cover, then the left side of the engine will be sealed up.

I finished cleaning a good amount of the head after that. Mostly complete on the intake side, and I've gotten a good initial scrub across the top. I'm about out of sand again, so I'll have to grab another bag this week. Next weekend I plan to work on the exhaust side before completing the top. And I imagine it's going to take some time to tape off all the machined surfaces, but then I should be ready for paint.

Temps dropped to 39 overnight, then back up to 91 during the day. Fall is coming fast, just a bit more work to get everything painted that needs it.

Progress is going slow on the head, but there IS progress. I have the majority of the head cleaned up now. The worst areas are in between the fins, but even most of that has been cleaned up now.

I had planned on working on it all weekend, but yesterday I ran out of sand and had to go get more. Then the tip broke on the sandblaster gun, so I called it quits. Nobody around here sells sandblaster parts, but the Harbor Freight just down the street is opening soon. In the meantime, I found a brass hose adapter that has the 1/4" NPT threads and a 3/8" hole through the center. That seems to be working great, so I was up and running again today for a few hours until the sun came around and the glare off the glass made me pack it up again.

Slowly but surely getting there. I'll tackle it again next weekend, but I also need to spend a day putting new plastic on the greenhouse roof before the cold weather sets in. At least the greenhouse won't be an overwhelming project like last year -- everything is built, I just need to cut and staple on some new plastic.

Getting so so close... I finished cleaning up the fines on both ends today, and have gone back to cleaning up spots. Lot of little places that just don't want to come clean easily, but I think I pretty much have everything around the sides cleaned up "good enough"... I won't get it perfect, but there's a lot of places that are pretty well clean and won't actually be seen. This piece is taking so long that I've lost any patience for perfection. Tomorrow I need to go over the top side once more, do a final check for anything that might still be easily seen, then get the primer and paint shot on it.

I hope you didn't get the valve seats with the blaster.
Steve

Oh I did, but my sandblaster is like the smallest gun that Harbor Freight sells. It doesn't have much power, which is why this is taking so long. I hit the chambers just enough to give them a scrub after scraping the carbon, but the valve seats are still bright and shiny. Plus they'll be getting lapped after I finish baking the paint.