ZA50 - anyone rebuilding them?

Have a ZA50 and looking for someone to rebuild it for me.

Re: ZA50 - anyone rebuilding them?

♣Slew Foot♣ /

Re: ZA50 - anyone rebuilding them?

Thanks, I had looked at the rebuild guide, but looking to hire someone who has experience rebuilding them for this engine.

Re: ZA50 - anyone rebuilding them?

Dude just do it, they're only complicated for a moped. Seriously I over thought it for almost a year then I jumped in and it wasn't too bad.

I'd say with digital calipers and a machinist dial you'd be set.

Read up on shimming.

Get the crank in with new bearings and original shims and use a machinist dial to measure how much the crank moves. If it's in spec then start it without the trans and listen and make sure it sounds ok.

Out of spec? Change the shims.

Another way is to measure the crank with the bearings on and match that width when you get the new bearings on.

Re: ZA50 - anyone rebuilding them?

Also deadped Ryan has a blog with the original tool all measured out. Really easy to replicate by a machinist shop or at home with a welder, my local precision shop was going to charge $200 which isn't too bad considering what someone would charge to rebuild it

Re: ZA50 - anyone rebuilding them?

I know, I probably should but I have so many other projects I’m working on and really want to have this running for the spring and I’m afraid I won’t get to it. I haven’t rebuilt a 2 stroke yet and have a couple Minarelli V1’s I figured I’d start with as they don’t seem too difficult. Maybe I’ll have the confidence after I get my first one done. I had heard you needed the factory tools so between that expense and the parts I thought maybe I’d send it out. Thanks for the info on the tools thread, I’ll check it out.

Re: ZA50 - anyone rebuilding them?

I really don't think anyone rebuilds them, I would not send anything to tomahawk mopeds which is the only place I can think of.

Re: ZA50 - anyone rebuilding them?

Thanks...I will read up a bit more and start putting my parts list together and see if I can convince myself to take this on lol

Re: ZA50 - anyone rebuilding them?

You got it, and record/share your process!

Re: ZA50 - anyone rebuilding them?

Ha, yeah it’s going to be a lot of steps getting this MKII back on the road.

Re: ZA50 - anyone rebuilding them?

I dunno if Ken Roff would do this kinda thing?

Re: ZA50 - anyone rebuilding them?

Re: ZA50 - anyone rebuilding them?

Let’s see what your za50 looks like? Is it in good shape? Did it run? Is there trans fluid or water in the case?

Re: ZA50 - anyone rebuilding them?

Most of the time unless the crank is frigged or the bearings are rusted, rebuilt za never last as long as original. Just pop the seals out and push some new ones in if you’re worried about it.

Re: ZA50 - anyone rebuilding them?

I’m not sure it needs to be rebuilt, but I just got this 1980 Puch Magnum MKII the other day and want to restore her. The piston wasn’t moving and after some PB Blaster it’s slowly moving. The person I bought it off of said it was sitting a couple years but had previously run until the carb and other parts were stolen. He said he never changed the pucks or did any work on it. I ordered a set of pucks and plan on hopefully this week to pull the head off of it and taking a look at the top end.

Re: ZA50 - anyone rebuilding them?

Here are some pics

puch1.png
puch2.png
puch3.png

Re: ZA50 - anyone rebuilding them?

Overpriced Parts /

Yeah someone did work on it, they removed the oil pump, If they removed the shaft and plastic shaft tube guide you’ll have an Huge air leak to case and the engine will never run

Re: ZA50 - anyone rebuilding them?

One of the members here who has one is going to be in my area this weekend is going to look it over and see what it needs and I’ll take it from there. Thanks for all the replies, much appreciated.

Re: ZA50 - anyone rebuilding them?

I just replaced the pucks and flipped the second gear clutch on mine, and put a fresh top end/pipe one. Geared tall to keep rpms below 8500 rpm. For me this is a treats piston port kit/head, mlm peoples sidebleed pipe, 19/37 gearing. This is the “fast but reliable” setup I was recommended to follow, without having to worry or mess with shimming assuming you put them back in the right spot. I did not the first time and it wouldn’t roll backwards. I also didn’t put the roller bearings against spring tension so the transmission never engaged lol.

From my understanding, once you mess with aftermarket cranks, you need to nail down the low tolerance shimming part of the equation. Supposed to be easier with the official tool but it’s rare, I’ve been hoping someone holding onto it sends one to MLM for reproductions.

With that setup so far not really tuned, I get 74cc e50 kit like acceleration off the line in 1st. Hitting low 40s. My other ZA is geared even taller at 20/35 so I guess it might last longer but this season will be my first with ZAs, I’ll probably be posting here on results.

Detroit Moped works used to be the go to but they only do small/quick local repairs now. The mods mentioned above are easy to do though, just need to make sure you correctly take off the right hand threaded nut, and grab the second gear locking tool from treats. The tool the holds the sprocket isn’t worth it, just use a 8mm socket, it’s useless once you change that front sprocket. (edited)

Re: ZA50 - anyone rebuilding them?

Overpriced Parts /

> Jacob Fulton Wrote:

> -------------------------------------------------------

> I just replaced the pucks and flipped the second gear clutch on mine,

> and put a fresh top end/pipe one. Geared tall to keep rpms below 8500

> rpm. For me this is a treats piston port kit/head, mlm peoples sidebleed

> pipe, 19/37 gearing. This is the “fast but reliable” setup I was

> recommended to follow, without having to worry or mess with shimming

> assuming you put them back in the right spot. I did not the first time

> and it wouldn’t roll backwards. I also didn’t put the roller bearings

> against spring tension so the transmission never engaged lol.

>

> From my understanding, once you mess with aftermarket cranks, you need

> to nail down the low tolerance shimming part of the equation. Supposed

> to be easier with the official tool but it’s rare, I’ve been hoping

> someone holding onto it sends one to MLM for reproductions.

>

> With that setup so far not really tuned, I get 74cc e50 kit like

> acceleration off the line in 1st. Hitting low 40s. My other ZA is geared

> even taller at 20/35 so I guess it might last longer but this season

> will be my first with ZAs, I’ll probably be posting here on results.

>

> Detroit Moped works used to be the go to but they only do small/quick

> local repairs now. The mods mentioned above are easy to do though, just

> need to make sure you correctly take off the right hand threaded nut,

> and grab the second gear locking tool from treats. The tool the holds

> the sprocket isn’t worth it, just use a 8mm socket, it’s useless once

> you change that front sprocket.

You kinda said that confusing, just to be clear The first nut you takeoff inside is a reverse thread nut, left to tighten, right to loosen

Using a 8 mm socket against the sprocket is a bad idea it puts stress on several bearings especially if it’s on tight, the locking tool is a must

Re: ZA50 - anyone rebuilding them?

Sounds about right, I don’t really know what I’m talking about much lol. I guess it’s not much extra work to swap the 18 sprocket back on for the purpose of the tool.

Re: ZA50 - anyone rebuilding them?

Richard Eberline in Trenton Michigan

Re: ZA50 - anyone rebuilding them?

Thanks everyone!

Re: ZA50 - anyone rebuilding them?

Just follow the instructions in the wiki for doing it without the factory tools. It is super easy and starts making total sense once you get in there. Have fun with it man. The only things that you will need to do is flip the second speed clutch and replace the pucks. I said replace the pucks!

Re: ZA50 - anyone rebuilding them?

Funny you just posted that as I just finished watching that video and a couple others. I’m definitely going to replace the pucks and flip second gear. I watched videos on that multiple times. My pucks are being delivered tomorrow that I had ordered. After watching the disassembling without factory tools video I’m sure I can take apart at least lol

Re: ZA50 - anyone rebuilding them?

Overpriced Parts /

> Charlie C Wrote:

> -------------------------------------------------------

> Funny you just posted that as I just finished watching that video and a

> couple others. I’m definitely going to replace the pucks and flip

> second gear. I watched videos on that multiple times. My pucks are

> being delivered tomorrow that I had ordered. After watching the

> disassembling without factory tools video I’m sure I can take apart at

> least lol

Some of those videos make me cringe

Get holding tools at least, Do not use a screwdriver to pry the clutch cover off use glancing blows with a rubber mallet.

Don’t bang the lock washer on crank nut without Support on other side of nut, don’t use flywheel holder to crank on the nut either you could twist the crank, use clutch holder tool

Do not over tighten the nuts torquing is spec is very important, You should check all shim areas, do not take it for granted that they’re in specifications because of wear or many times there’s two shims on each end sometimes people lose one of them.

The Torrington bearings on main gear shaft many times are seized up, free them up or replace it with the newer style needle bearing if your Za50 engine doesn’t have the newer style needle bearing already in it

Re: ZA50 - anyone rebuilding them?

Thanks Ken, that’s good info there. Hopefully after this weekend I’ll have time to start digging into this and I’ll post some updates.

Re: ZA50 - anyone rebuilding them?

Yeah there are some really bad za videos out there, the david fixes his shit one has a few 'fatal errors'

I dunno if the little one i did makes you cringe, Ken, hope not, I've had good luck doing them that way but I use rags and support the shaft.

I've been making some videos but progress is slow and the ZA one is going to be a ton of work.

Re: ZA50 - anyone rebuilding them?

I honestly have not watched the videos when attempting my first rebuild. Only the tutorial with some pics. I just laid everything out on a nice white cloth and didnt lose a thing.

I have not found the need to reshim any of the za50's I rebuilt but nothing was too far gone in them to cause excessive wear in the tranny. And if the mileage is less than 3k you should be fine with the original shims. I believe it is at 3k they advise checking out the shims but I might be a little off on that. The manual I have is only for an e50 but that is when they advise doing transmission work.

Ken and Graham are really more the gurus of this realm so definitely consider their words carefully.

Re: ZA50 - anyone rebuilding them?

I agree with Daniel and Jake. - don’t split your cases unless you have a shitfucked crank and/or bearings.

Just clean & rebuild your trans, inspecting every part for weird play and / or ware and installing new pucks.

If you are putting a performance top end; you’ll want to flip second while you are in there and grind the cases to fit a larger front sprocket to keep rpms down.

I wouldn’t do the seals unless you have a leak; but it’s easy enough either way.

I’d swap the oil inject block off plate with one from treats and inspect it / how they removed the oil injector shaft.

As Jake mentioned; we won’t do full mail in za50 rebuilds At DMW any more; and I no longer have the time / staff to fully tune bikes with performance work done - BUT I actually will do all of the stuff that I mentioned above short of the full rebuild as a mail in service if you still want to pay to have it done.

If so, send our FB page a message or fill out the contact for on our website.

Thanks. Talk to you soon and/or good luck with the build!

Want to post in this forum? We'd love to have you join the discussion, but first:

Login or Create Account