Age seized Supa 5

[Pat the Jawa]

I was lucky enough to be given a rusty heap masquerading as a TS250/1 - I did however have to pay for a motorcycle transporter to collect it from the IoM. On first inspection my initial reaction was what a rusty pile of s**t and what the f**k have I gone and done now! The worst discovery was that the engine was seized. I thought in for a penny, in for a pound and set to getting the barrel off the piston. With no exaggeration - I literally beat the piston out of its bore with a stout section of wood and a large lump hammer. It must have taken me a good 20/30 minutes of hammering even with that much force. Now then, you ask why am I writing this down? On close inspection​ I was amazed to find that both the barrel and piston were near as damn it undamaged! The rings were seized in their grooves however - managed to free the lower two but had to break the top ring into pieces to remove it. I have since bought a new set of standard rings (MZ Parts Bristol) and fitted the piston, with its new rings, barrel and head onto the bike I'm currently riding. The bike I ride has done 51,000 miles whereas the replacement barrel and piston have only done just over 10,000 miles. The engine pulls fractionally better but to be honest there's not a huge amount of difference. The moral to the story is don't give up on an MZ even when it looks bad!

[Pat the Jawa]

Further to the previous post: the big end, little end and main bearings are all fine so even though the engine looks to be one lump of white corrosion, it's still usable. I've also rebuilt the front wheel with stainless steel spokes having cleaned the hub with a bench grinder mounted wire wheel and loads of elbow grease to polish the rim. Again, the corrosion looked a lot worse than it really was. The front wheel rim still shows slight signs of the corrosion attack but still looks great - good testament to the quality of MZ's aluminium!

[breakwellmz]

I hope you took some`before`photos to compare with the `after`ones when it`s done.

[Blurredman]

I'm glad it went well.

I have also had a similar experience within the last year with a 1990 ETZ 251.

13 years it has been off the road and discarded. Half of it's life! I had to do exactly the same, but unfortunately the barrel will need a re-hone and the piston will require replacement as I had to batter the hell out of the crown to get it out.


In the mean time I put on a spare 250 barrel piston and head that came off my MZ that I put 300cc on.

The other problem (which still persists) is the extremely rusty internals of the petrol tank which I cleared as best I could and the completely gunked up carburettor. A good cleaning with boiling lemon juice and rubbing of various places got rid of most of the gunk and unsiezed the float. I bought new jets however and it did still take a month or two of fettling to finally flush out the various (thankfully few) internal channels of solid crud. And then finally tune it properly. (I much rather like ths 30n3 carb!)



I bought an Zaplony electronic ignition after a factory original failed on me and a cheap Hungarian varient from MZ-B didn't work at all. That solved the issue of unable to time the bike (you just couldn't adjust the point gap correctly for whatever reason.. even with different rotor, cam lobe, stator etc etc..) During this time I bought and installed a cheapo (that under reads by 0.3v) voltage display so that I could tell what the charging was doing, how and when.


Last was to solve was why the bike kept stalling throughout my time of ownership. This turned out to be a dodgy coil. Now the bike is 2,300 miles in my use, with 1,300 miles of perfect running. First 6 months was hell trying to resolve each problem one by one, but since solving the coil it has been my commutor bike and has proved reliable, smooth and efficient at a constant 65mpg around city riding.



So I'm glad that other people persist in getting a bike that looks well abused and battered into working condition again. Don't get me wrong, this bike is only to get me to work and back on. It has rust everywhere including external bodywork and wheels and frame but the purpose of my pursuit was to get it on the road as cheaply as possible. With mismatched indicators and rear lamp from ETZ250's

[DAVID THOMPSON]

making a bike look too good will get it stolen
and
here they request that if its rusty some paint needs applied
"rat" bikes do not pass inspection if there toooo ratty
this started years ago when some riders decided to ride things that were mechanical ok

but looked like a rolling piece of junk from hell
DAVE

[Pat the Jawa]

To be honest I didn't think to take before and after pictures of the front wheel as I had no idea it was going to come out so well. I'm yet to do the rear wheel so will get some before pictures and post them along with the after pictures of front and rear wheels!

[Pat the Jawa]

The plan with the rust MZ is to swop any good bits over to the MZ I'm riding and sell the rest as I haven't got any storage to keep it. I can rebuild the wheels from the rusty MZ whilst I'm still riding the good MZ and simply swop them over when they're finished.

[Pat the Jawa]

Further to my last post back in June I've been steadily rebuilding the rusty MZ bike. I had fully intended on simply keeping it for spares but under all that rust/corrosion it wasn't actually too bad and I felt sorry for the poor thing. The rebuild is going very slowly as I've been quite ill since last September but it is still moving forward gradually. No doubt this will upset the purists but I've changed quite a bit of the bike simply to suit me - higher alloy handlebars, dogleg levers, Japanese style cheap Chinese switchgear and replacement headlight brackets. I also did a straight swop with the17.5 litre tank for an original TS 250 12.5 litre tank. It is basically the same tank as the 125/150 but has the correct mounts for the 250. Was very lucky to have the tank repaired, filled where necessary and professionally resprayed black - finished off with new chrome tank panels and rubber knee pads. I'll see if I can get some pictures as the rebuilding progresses.