My MZ turned into a ZM

[Lone-Wolf]

Wotcha.

Took the ETZ 250 for MOT today - passed with no problems.
Seeing as the weather was not too bad, I decided to carry on down to the Severn Valley and have dinner in the cafe.
Whilst waiting at a set of traffic lights the bike began to run very rough - making a noise like a blowing head gasket . . . .and for good measure my rev counter wasn't working.
I kept the engine running and decided to head back home . . . . the lights changed to green . . . .I let out the clutch . . . . and went backwards

I've had two strokes run backwards before, but never a running engine which had managed to reverse direction without cutting out.

On the plus side - when I re-started it, everything worked like it should . . . .and I did get down the cafe for dinner.

[DAVID THOMPSON]

Harley Davidson golf cart motors did that for years for reverse
the motor was a very bad copy of the rt 125 2 smoker

at least you did not back into someone tailgating

check your points it may run good but be a bit out from where it should be set

[therealche]

Whilst waiting at a set of traffic lights the bike began to run very rough - making a noise like a blowing head gasket

I think what has happened is when it made that noise, it did actually stop momentarily while on the compression stroke , didnt go over TDC and flicked back and restarted ZM stylee! Ive had it happen once and it was as if the engine coughed!

As David says check your timing!

[DAVID THOMPSON]

needs to be a bit closer in time
and idle may be a bit on the slow side (idle equals tick over in uk English

therealche ...tell us the proper idle on that one .. i have not owned a 2 smoker for many years
but i am thinking at least 1200 UDM/RPM
dave

[Lone-Wolf]

Wotcha.

It idles at around 1100 to 1200 rpm.
Timing hasn't been checked in the last 12 months . . . I'll check it.

Just ordered a new Mikuni VM30 carb for it - something I've been meaning to do for the last twelve months.

(EDIT)

The carb arrived the day after I'd ordered it - Allens Performance supplied it already jetted to suit the ETZ.
Spent a good three hours on the lathe making an adapter to fit the Mikuni to the ETZ air filter tube.

Fitting the carb back on was a struggle, but I got there in the end.
Not had chance for long test ride, but the mile or so I did around the block seemed promising.

[breakwellmz]

Your timing is way too advanced if your engine can run backwards!
That`s how they used to get reverse on some of the old`Bubble cars`-two sets of points and a switch between them.

[Nedtwolegs]

Happened to me once on a DT175. Never heard anyone share the same. Good to know it wasn't personal.