black plug

[steveomz78]

Hi guys can you help. recently got my old 78 reg mz ts 250/1. it runs, but not as it should, power seems to die gradualy, if i drop a gear and open her up she rersponds for a while, then the same happens again ( i am not labouring her ) checked plug on return, blackish & slightly wet. plus there is wet blackish fluid spitting out onto crank casing from below where exhaust fits to casing. thanks in advance for any help you people out there can give me regards steve

[Old Dog]

You mixture is too too rich.
You need to
1. Check that the airfilter is clean and dry
2. Check that the exhaust isn't clogged
3. Check and decoke the piston and head + replace the plug
4. Clean out the fuel tank and replace with new fuel and correct mix of 2T
5. Clean up and set up the carb.

Assuming your timing is OK it should run as sweet as a nut and have a light brown plug like my ETZ

[DAVID THOMPSON]

and if the points have been it many years the tension spring could be loosing it spring
which will make it run bad
the times i have had the problem it would idle fine but would not run at medium to high rpm
dave

[steveomz78]

Thanks for the advice guys, will try some of them, when i get time although, i am not sure how to de- coke head & piston, nor do i have any experience at setting up carbs. regards steve

[Old Dog]

You will need a manual - copies on ebay or from MZ riders club (UK) and or haynes.