301 engine please

[Badboydas]

Cheers
good info. The bike I have was a donor for the MZ racing scene late model 93 which I think means it was made of all the left over bits just before the factory closed its doors. Anyway hopefully Robbie will come up with the goods at a reasonable price, not that the price actually matters that much?
cheers Billy

[Badboydas]

Good news a 301 is on it's way down to sunny? Dorset. Robbie from the Facebook MZ Riders Club came up with it at a very reasonable price. Robbie's wife runs a MZ recyclers at http://rcrmzspares.webeden.co.uk/ worth a look they don't just sell you a corroded oily part they clean it up for you. I'll get a picture up once it's running.
cheers all for your help

[stinkybob]

The only 300cc MZ engine I've ever had was a bored out standard ETZ250, apparently a Wilf Green thing they did before MZ made a 300 or something like that. It didn't use an MZ piston (apparently) and I've heard somewhere it was a Suzuki piston or something. All I know is that whichever piston it was the size was ever so slightly smaller than what MZ eventually came out with so when I did a rebuild some years ago I had to widen the bore with a vigorous hone job before it would take the new MZ300 piston, but now it runs a standard MZ 300 piston just fine. I still run it to this day and the extra 50 cc's is definitely a good thing.

A 250 engine CAN be tweaked for more power and it's fun to do but the 300 rebore is easy and cheap and does the job well. The head, if it's the original 250 head, has to be rejiggered to accommodate the 300 piston crown but that can be easily done by anybody with a mill. There is no difference to the bottom end so nothing has to be done there.