Thread: Z50 ressurections

Well I've been lurking long enough stealing your information, I'll try to keep my rebuilds updated.

Note these will not be restorations, not even close. I'm just simply going to go through the two bikes to have a pair of reliable pit bikes, campground bikes, something anyone can jump onto and take to the next campsite or concession stand. They will be nice, but they will not be in new condition. I won't be spending a lot of money on them, and a lot of parts will not be correct. Some things will be done that will make the purists cry, and hopefully I'll keep enough of the spirit of the original to get a thumbs up from them as well.

Started today with the 77. Swapped in a Lifan 83 cc manual clutch 4 speed unit.

Kind of a pain. I'm sure there are some parts available to make it all fit perfectly, but I prefer to work with what I have.

The motor bolted in fine. The carb and intake bolted on fine. The throttle cable though gave me a whole lot of grief.

The throttle cable is meant to come straight up from the top of the carb. The original Z50 part has a tube to take the cable out at 90 degrees to clear the gas tank. Well I manufactured a tube to thread in, modified the cap on the carb, brazed peices together, modified my custom pieces. I pretty much spent the whole day trying to attach a throttle cable to the carb in a way that would clear the gas tank.

Eventually I gave up. Trying to get to the right cable length using a Z50 cable and throttle while having a bent tube attached to the carb was proving difficult, and was going to result in having to shorten the cable housing. Not only that, but it was still going to require a dent in the gas tank.

As it got dark outside I went for the simple sollutions. I grabbed a throttle and cable off an old Suzuki 50 that I had in the yard. Did away with the adjustment collar on the top of the carb cap. Drilled out half the threads in the cap to drop the cable housing in a little further. Bolted it all together and it worked fine with the perfect amount of freeplay.

So, to make the tank fit. Not only did the bottom of the tank want to kink the throttle cable, the tank petcock also hit the carb preventing any sort of air cleaner to be installed.

A little denting of the inside of the tank for cable clearance, and some bending of the fuel fitting to direct it away from the carb, and everything is happy now. I can hear the hate mail generating already. Not to worry though, the tank is not in the greatest of conditions anyway, I found several pinholes sealed with bondo today, and although I had previously been running this bike, the gas I poured out of it today had a whole lot of rust flakes in it.

As I was sanding off the ugly brown paint, Bonus! I found the original Honda graphics were still there under four layers of different color paint. Yep they're beyond restoration, but I might just sand the rest of the tank to match and give it a clearcoat for that patina look

Making the manual clutch work was a bit of a challenge too. Not that it was challenging making it work, but getting someone to sell me a clutch cable was a challenge. Everyone kept arguing with me when I asked for the shortest clutch cable they have. Nobody wants to sell you anything without an application. When I try to explain its a Z50 with an aftermarket motor in it, I get the blank stares and they insist that I can't put a manual clutch on a Z50

Finally four bike shops later I found a guy who would finally just give me the shortest Honda cable they had. I clamped on a universal clutch lever, a little time adjusting, and I think it works very well.

Then it was time to make it run. It seemed simple enough at the time. A lot of frustration, and a couple hours of consulting the internet, it seems I need a CDI box to go with this Lifan engine. Ahh the things we learn too late. I'm actually having trouble finding anyone that will admit a Lifan 86cc manual clutch engine exists, let alone someone that has a CDI box for it. I have found one supplier online who seems to have what I need, I just have to figure out how to ship it without getting charged more than the retail value of the part

That is all for today. Enjoy

Most people refer to the 86cc Lifans as 90cc. I reckon most chinese cdi's will work, i have used the same one on a 110cc and a 140cc. I have a 125cc in my 75 z50 with a chinese 26mm carb(more like 24mm) and i managed to make it all fit. I moved the petcock forward about 3 inches and brazed over the old hole. I opened up the mount holes on the manifold so i could swing the carb inwards as much as possible. I had to put a 10mm rubber spacer on the rear tank mount to make it clear the carb and the throttle cable just fits between the tank and the frame.

thanks for the info, I'm not sure why I didn't think of just moving the bung, I don't have a welder that can handle something that thin but I certainly could have brazed it.

my other Z50 needs the tank cut open to clean out the rust anyway, so if I find another Lifan I'll modify the tank as I put it back together.

bought a CDI box on ebay. $12 shipped lol.

Exhaust. eek.

What do you use for exhaust? The original honda pipe does not fit the new motor due to the depth of the exhaust port, and also it does not clear the clutch housing and linkage

Funny this was supposed to be a build thread, and I'm asking questions instead.

i bought a chinga header pipe and welded it to the original pipe

and bent the front of the chrome heat shield so it fitted to maintain a semi stock look

I had one pipe bent in a way that it would clear the clutch assembly, and I realize now I only had to weld a spacer on the end of it to take up the extra depth\

but I saw this pipe on Ebay and I had to have it


Can you think of anything else weird that I'm going to have a problem with?