ETZ 250 / 301

[Andy_C]

Thinking about comming back to MZ but really fancy a 301.

I did have one for a while and really regret selling it.

So been thinking, if I had a factory 301 cylinder, do I just have to machine out the opening in the 250 cases to make it fit, or do you also need to do some machining on the transfer ports for things to match?

Positivley hate the look of the 301 Kanunis, so been thinking about getting another "proper" ETZ 250 and converting it, mind you not many ETZs at all for sale around these days.

Thanks.

[Guesi]

You also need another cylinder head...

[Andy_C]

You are of course right, I am sure I have an article someplace about re working a 250 head to suit.

Believe you can bore out the standard 250 cylinder to accept the 301 piston, but the wall of the liner becomes pretty thin.

[Guesi]

Yes you can. This is done often, because the original 301 cylinders are quite rare...

[Andy_C]

Guesi.

Thanks for all your help, might see if I can find an ETZ 250 that I can convert to 301 spec in that case, but there seems to be very few of them for sale in the UK at the moment.

Something may turn up............

[lavrentyuk]

I may well be missing something (had my codeine for the evening now) - but why don't you just put a 301 engine in the 250 chassis?

[Andy_C]

I did say in my opening post "been thinking about getting another "proper" ETZ 250 and converting it, mind you not many ETZs at all for sale around these days."

Must be the codeine

[lavrentyuk]

Must be, though my inner pedant doesn't see the clash.

Could be the best of both in many ways - though I retain a hankering for a Supa 5 with a disc front end and 12 volt conversion.

[Andy_C]

I always wanted a Supa 5 - allegedly they are the "best" I am told.

I did manage to get one a few years back, problem was that it was physically too small for me, so I sold it on, the ETZ is that bit bigger.

The 301 that I had was a Kanunni, so it looked rubbish but went really well. The ETZ 250 I had was pretty good, only sold that due to issues with the seat, why I did not just get it sorted I'll never know.

So the thnking is an ETZ 250 converted to 301 spec - just have to find a suitable ETZ 250, but very few seem to be coming onto the market.

[DAVID THOMPSON]

my 2002 rt125 is a little small but i never got tired of it and it still runs with a bout 24000 on it
it scares guys that don't know its a 125 the crooked roads we have here it is super fast on and i get at yelled at all the time i go to fast
on it it ii"s a fun bike
dave

[lavrentyuk]

My fastest 2 stroke MZ was definitely the Kanuni 301. That thing really shifted, bought new in 1997 from Jack Nice. A few weird slight differences from the German models - like the pitch on the speedo drive at the rear wheel. Why? Parts of it live on in my current ETZ300.

[Andy_C]

Interesting, the 301 that I had was a Kanuni.

I bought it as a very rough non runner, and when I got it going I was suprised at how well it went, perhaps a "factory" 301 is the best option.

Perhaps the better route is to buy a Kanuni and throw away the god awful tank / fairing etc and replace it with ET hardware.

More options

P.S. No disrespect to anyone with a Kanuni - I just dont like the way they look.

[Blurredman]

As someone who has an ETZ250 with a 295cc piston in, I'm not sure it's really worth bothering. There's a bit more torque I suppose but in all honesty, I'm not sure i'd bother. The very fact that I have a 76mm piston in the re-bored 250 barrel, and a slightly machined head, makes me wonder if I should sell it on now and put my original setup back, whilst the 300 is still usable, because once this piston/barrel is scored/unusable for whatever reason, it's very unlikely it will take another rebore. You can get 76.5mm piston but that's the very limit.


I have an 18 tooth front sprocket, and I've been thinking about putting the original 19 tooth back on, it might make me feel better about the performance then too.

[Andy_C]

Food for thought.

Sounds like a factory 301 is the best option if going down that route, since you should be able to rebore it.

Might be best just sticking with an ETZ 250 though, the last one I had was pretty damned good, but from memory the 301 had a bot of edge over it.

I'll see what comes along I guess.

[lavrentyuk]

Not all Kanunis came with the ugly tank. The early ones had a near standard shape tank, but not the usual ETZ fuel cap. I have a later Kanuni tank next to a late Kanuni example on a shelf in my garage. The later one may be ugly - but is huge - which has an advantage in itself I guess.

Meanwhile you have identified the solution - take what you can get, that way you have an MZ and can come out to play.