The Nightmare CZ

[PotatoHead202...]

So for some godawful reason I decided I wanted an old two stroke last year. No, I didn't go the (relatively) sensible route of something like an Aprilia RS125 (like I passed my test on at 17 back in 2008) but rather chose a piece Eastern Bloc ste.....

After about 9 months I finally feel like I'm getting somewhere with this build. Bought it last year for about £300. It's turned into Triggers Broom......

Original 125 engine threw its main bearings shortly after getting it running - but miraculously still ran. I rebuilt it as a 175 with a new crank, barrel, piston and head (the cases and gears are the same as the 125). All bearings are now SKF.

Secondhand front wheel as original was rotten,
New stanchions (8 weeks to get here due to Czech snail Post and customs)
New chain,
New 6v battery,
New cables,
larger 26mm jikov carb,
Secondhand exhaust,
Rewelded steering stop,
Various parts powdercoated,
New gearbox dogs,
Secondhand dynamo off another engine (originals brush holder snapped)
The list goes on.....

Painted in two part rustbusters epoxy. Oh, spent fking HOURS drilling out the centrestand bolt that had seized solid as somehow the centrestand spring was missing and can't be refitted without removing the bolt.

Electrics were also a bloody nightmare. Someone had fitted tinfoil into the fuse holders and all bulbs blown. Had to get help with this as 6v electrics are a total mystery to me.

Brakes have been rebuilt as well. Drum brakes being a first for me.

Hasn't been on the road since 1991.

Rebuilding had been a nightmare. Parts diagrams are of appalling quality, nobody uses parts numbers, torque figures don't exist etc etc etc

With any luck it'll be MOT ready in another week or so
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Suzuki V Strom 1050XT, Honda CBF500 ABS,

[blurredman]

Looks good to me,

That all sounds like very standard stuff on getting an old vehicle on the road though, Eastern or not.

Good luck on the MOT.
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CBT: 12/06/10, Theory: 22/09/10, Module 1: 09/11/10, Module 2: 19/01/11
Past: 1991 Honda CG125BR-J, 1992 (1980) Honda XL125S, 1996 Kawasaki GPZ500S, 1979 MZ TS150.
Current: 1973 MZ ES250/2 - 18k, 1979 Suzuki TS185ER - 10k, 1981 Honda CX500B - 91k, 1987 MZ ETZ250 (295cc) - 39k, 1989 MZ ETZ251 - 50k.

[A100man]

It's a fine looking machine - you are truly blessed. I'm particularly fond of the screwdriver brake lever pivot. It's an exciting detour from the mundane shouldered bolt
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Now: A100, GT250A, XJ598, FZ750

Then: Fizz, RS200, KL250, XJ550, Laverda Alpina, XJ600, FZS600

[Rob Fzs]

I remember my ex's grandad saying he used to have a CZ, it was that bad he left it in a ditch and abandoned it
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'00 Aprilia RS50 > '92 Honda CG > '99 Yamaha Fazer > '91 Yamaha RXS > '79 Suzuki X5 > 01' Honda Cg > 07' Honda Cg > 82' Kawasaki Z200 > suzuki gsxr 400 gk73a > honda vfr 400 NC30> Yamaha RD350 YPVS F2 > Kawasaki ZZR 600 D1 > Yamaha TZR 250 2MA >Suzuki TL1000R > Yamaha TDR250 > Honda 929 blade > Suzuki SV1000 > Honda H100
Mod 2 Passed 09/06/2011

[Nobby the Bastard]

[stinkwheel]

You can't say you weren't warned ... Says the man who has several boxes full of Minsk 125 sat in his shed.
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[slowasyoulike]

Looking good! Best of luck with the test

[Robby]

The post has a tone that suggests, now all of that work is done, it will now be an MOT pass and plain sailing afterwards.

I would suggest a top box to carry the tools you'll need.

[Nobby the Bastard]

[that_impulse_guy]

its made it this far in life already. It'll be fresh for another 20yrs after you're done with it. Most things like this is a case of undoing previous cheap mods and doing it right, whether that was bad from owner or bad from factory.
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Gone: Yamaha DT50lc, Suzuki DR500, Suzuki A100, Kawasaki z250ltd, RD350YPVS, Suzuki DR Big, Kawasaki AR125, Kawasaki KMX200, Suzuki GS1000S, Katana 1100, GS550M, Suzuki RGV250
Now: Suzuki GSX400X, Suzuki RF900R, NS400R

[PotatoHead202...]

Oh, don't get me wrong, I'm not expecting plain sailing. About the only thing that hasn't been taken apart and worked on/changed is the swingarm bolt - as it's siezed - but the bushes are still good and no play. The shocks are also brand new from NJB Engineering. If the bushes in the SA do go then I'll drill the bolt out but could do without that arsehole of a job right now!

The only thing that really concerns me are the electrics. They've also been largely replaced, new points along with the condenser and brushes. The lights are obviously shockingly awful and probably downright dangerous for night use. If I didn't have to get new stanchions for my VFR (slightly pitted although not leaking but it annoys me to look at) I would have bought a VAPE electronic igniton kit - I may yet. The general maintenance of the points system is a mystery to me so will be leaning on friends to teach me.

The screwdriver pivot will be removed soon as the bushes for the levers arrive......

I've got a 100% reliable VFR1200F to fall back on and a pretty reliable CBF500 as well.

If it doesn't cause me too much bother over the coming weeks I'll be going to the owners meet in Nantwich at the end of June. If it hasn't caused me to totally lose the plot I'll also be taking it to the Dragon Rally next year in place of the CBF that usually goes.

I have no illusiion that it'll likely be absolutely terrible in practically every regard but that is half of the fun!
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Suzuki V Strom 1050XT, Honda CBF500 ABS,

[PotatoHead202...]

[PotatoHead202...]

[stinkwheel]

When it comes to it, I've seen an air chisel with a bit of round bar in place of the chisel used to good effect to remove a stuck swingarm pivot.

The trouble with the dynamos on most of those jawa/CZ bikes is the brush holders are made of bakelite which degrades over time and crumbles to bits. Don't know if there's a good solution short of making up a replacement brush holder out of something more robust. I suppose in the days of 3D printing that becomes more accessable. Maybe even making up a silicone mould from a new set and "casting" some in thickened epoxy? People used to make new brushes by cutting/filing down old washing machine brushes.

Swapping out the charge relay for a modern one is also not a bad idea. If the relay fails, your charging system fails. When that red charging light comes on, you are no longer charging, even if it was caused by the charging relay failing.

The VAPE systems are excellent. Fit and forget. Only downside is the price.

if you can get hold of the skoda points, they have contact surfaces made entirely out of the contact material, the CZ ones are a thin sliver on base matal which can errode through distressingly quickly. Especially if you use resistor plug caps and/or plugs.
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[A100man]

[PotatoHead202...]

[stinkwheel]

[PotatoHead202...]