ZA50 End Play Float Measuring

Since my ZA50 (pronounced ZAH50, like short for Pizza, as in "hey lets order us som 'roni 'za") refused to roll backwards, that was nice enough to allow me to realize it was shimmed incorrectly. I have not the factory tools to measure, and even though they work very well, it isn't really a measurement so much as it is like a mechanical version of putting your fingers apart from each other on the back of a frame you want to hang up, and then moving them to the wall to make pencil marks. So with the advice of Mr. Mike Mike Naz, I went and purchased myself a machienst square, which was about $12, and a new battery for the shops digital calipers, which was $6. Oddly enough. So using the straigt edge, I was able to accurately measure the distance from the case, including the gasket, to the inner bearing race, as seen here. Credit goes to Dean, who had to take this picture twice as the first time I was incorrectly measuring the other bearing by mistake. Then using the straight edge, it gets a little trickier to measure the gear of the bellhousing, but not too difficult once you get the hang of it. Take several measurements until you can get a consistant reading. Take the two readings, subtract the bellhousing from the case measurement, and you have your end play float. Mine was .6mm with no shims. The factory specs are .05 - .25mm, which is as Chuck suggested, about the thickness of a Dr. Pepper can. Since I want to stay away from aluminum in this engine. The shim that I had in there was .6mm, and to land right in the middle of the float range, I wanted a .3mm shim. Since there were no local places that I could think of that might cough up the shim, I attempted to sand my shim down .3mm. All I really did was end up sanding my finger tips off, at which point I gave up and used power tools, effectively ruining the shim. That's fine, McMastercarr has the exact shim I want in a box of 25 at .1mm thickness for only $5. So I can stack a few here and there to get the height correct and be happily riding doubles in no time. Naz also suggested that I remeasure the float after a few miles since the bushing he machined for me might settle in a bit. No problemo!

Za50 Shimming

Sadly, I'm reporting a hang up in the re-assembly of the ZA50. Having the new bushing made was necessary, but it seems to have messed up the end play float on my crank shaft. The crank is engaged when I try to push the bike backwards, meaning the crank is binding. So I don't think the bushing needs modified, but the crank does need to be re-shimmed. Sadly, I don't have the tools to do so, and I'm not sure of anyone in the Seattle area who does. I might just have to out source this one and mail the engine off to Motion Left Mopeds, the leader in ZA50 tech. Not a big deal, just hoping to slap it on and go, ya know?

Ebay

How does a fellow get so much money to spend on mopeds that he can afford to buy exhaust pipes just to play them like instruments and make videos?

Sell the silly little moped things you remove from your bike on ebay.
Take for instance, this windshield that was on my Vespa Bravo, that the new owner decided was too dorky. She didn't want it, so I quickly offered to remove it. Now I was thinking I would get maybe $40 for it, but check out this auction now, huh? Freeeeeeeeeeeeeeeeeeeee money!

A55 Biturbo

Volumes a little weak on this one, obviously this pipe is a bass.

ZA50 Part 3

As I reassembled the motor, I found that I hadn't clearanced the case enough, and my piston hit the edges of the bottom, as you can see in the top left corner of the piston here. I know, a piston is round and can't have a corner, but use your imagination. So apart it comes again, a little more dremel and it's back together. Then I gaped the rings properly to .014, and then also found the piston wouldn't fall through the cylinder with the rings removed. So after dropping it from each side and switched around I found it was hanging up at the cylinder skirt, and not clearning the exhaust port. So after some honing I was able to get the piston to drop almost all the way out, which was good enough for me, since it really only needs to smoothly clear the exhaust port, which it does. Kind of curious about the quality of the kit, but it looks solid, even though it needed quite a few touch ups. The ports were razor sharp, so I took a riffing file in there and smoothed 'em out. That slop in the bushing I was talking about has been remedied, Michael Mike Naz spent a few hours on the lathe turning me out a beautiful example. A little bit of finish work once it was pressed onto the crank and the bellhousing spins like a mad man, only it doesn't slop around anymore. It took a little bit of encouragement to make sure the oil holes lined up. I finished my re-assembly, oiled it up and I'm going to toss it on the Magnum right now. Hooray!

ZA50 Bushing

As I reassembled my clutches, I realized there was lots of slop and play in the bell housing. I tried to convince myself it was okay, since the bellhousing rides mostly in the outer case bearing anyway, but I couldn't put it back together, and then after talking with Naz, who had a ZA50 apart to reference, we realized that my bushing was very worn. Curious why it would wear so much since the engine was rebuilt about a year ago, although I didn't inspect it at the time, so I don't know what it did look like. Since old Naz is a wizzard at all things lathe related, he is going to try turning out a few of those for me, and I'll be sure to snaps some nice pictures of them. I might also try some of my secret sources to see if I can track down some NOS bushings, because I'll bet these things take at least an hour of time to turn correctly, what with the flat spot, little teeth and oil holes.

ZA50 & Metra 80

To fit the 52mm cylinder skirt of a Metra80, or any Puch 80 kit, you need to open up your cases. Most people use a dremel by hand and do an okay job. The best way to do it is to use a mill and have it nice and even, so that the skit sits evenly in the case and transfers heat uniformly, but usually it's not a big deal. To open my cases up, I picked up two 60 grit 2" flap wheels, and a 120 grit 2" flap wheel. They chuck right into your drill, and 2 inches is almost exactly 52mm. So you simply sand away that material, leaving a wonderfully nice smooth surface. It took about 10 minutes of drilling, including some time to change the wheel after it staretd to get dull. It came out very nice, much better than a dremel job. I also took a nice new dremel bit and opened up the ports to match the gasket. They are quite large. The 2nd speed clutch in my bike has been flipped, and it looks a tiny bit marked on the inner side, but I'm not sure why this would be. Doesn't seem to be a problem to me, though.

I'm having some trouble with the actual cylinder, but that will be saved for another post.