Way more than I would have wanted to go for a bike with such compromised cosmetics.

There were a couple of Rotax 500 engined MZs at the MZRC AGM / 50th Anniversary Rally, both the Country off-road styled versions & one had a chair attached.

Didn't get to talk to the owners of those, but did have a chat with another Country owner (who had come on an ETZ250). He said that the Rotax was an easy engine to work on, only requiring a special flywheel puller. All engine bearings were standard sizes. Parts could be pricy, but there was a place in Leicester that sold ex-WD parts and if the parts required were used on the military Rotax engined bikes then they could be had for reasonable prices. He had been told before he bought his bike that the starter sprag clutch issues were caused by the engine kicking back when stopped using the ignition switch - the engine has light flywheels & when running down it could kick back kwhen coming up to compression. He stopped his using the decompressor, which allowed the engine to coast completely to a stop with no kick back & had had no sprag issues. Kickstarting could be problematic - a combination of low geared kickstart & those light flywheels again. Sometimes it would start on the kick first kick, other times it just would not start at all. He must have confidence in his bike, as he was starting a two-up trip to Romania this coming weekend.

Another (fairly catastrophic) issue was due to installation - the Rotax engine used thin wall magnesium alloy crankases, which could split through the main bearings if the engine was mounted without support at the front of the cases i.e. suspended from the cylinder head & rear of the cases only. Apparently this affected some race bikes that used such an arrangement. The MZ installation in the Country used an additional front downtube to support a cradle running under the engine & attached to the pillion footrest mounts on the ETZ251 derived frame to provide the required support.

As the engines of the two bikes on site had similarly scabby painted engine parts to the Silver Star, I wonder if a high magnesium content in the Rotax castings might be responsible - magnesium being far more corrosion prone that more basic aluminium alloys. That would be another reason for me to shy away from bikes using this engine.

Light flywheels seems to be Rotax trait - the Aprilia Caponord ETV1000 I made the mistake of buying was similarly afflicted. Doesn't make for a pleasant riding experience IMO, so I am now even less inclinde to look out for a Rotax 500 engined bike.

Nigel B.