timing

[bob griff]

hi i recently got a 1986 ts 125 it had been laid up a while but after cleaning the carb and fuel tap it fired up and runs well . it just kicks back a little when starting i dont know much about 2 strokes but timing must be critical ,can anyone let me know had to check/adjust the timing thanks bob

[djsbriscoe]

Hi,
A timing tool can be bought from Burwin motorcycles in London by mail order

Timing tool for MZ 2 strokes.

It's item P000149 at http://www.mzspares.com/toolsengine.htm

The tool is screwed into the spark plug hole. The sliding metal rod has markings spaced every millimetre. (The adjustable cable tie is my addition).

To use this tool you have to turn the engine so that the piston is at top dead centre. When the piston is at TDC the sliding rod in the tool stops moving up or down. Then you turn the engine backwards so that the rod drops by 2mm (2 gradations). This is the setting at which your points need to be opening (assuming that the timing required is 2mm before TDC). This can be checked by connecting a 12v bulb across the points. When the bulb lights (ignition on obviously) your points have opened.
I assume that you now have an idea of the procedure.

HTH,

David.

[bob griff]

david, thanks for your help i will get a timing tool . do you think that the kick back would be caused by incorrect timing cheers bob

[djsbriscoe]

Hi,
Not sure about that? I just remember having quite a few bruises from the kickstart lever hitting my leg when I last owned a 2 stroke. They all do that is my guess.

David.

[Spitfiregoggles]

My ETZ 251 kicks back most times I start it; even after I've checked the timing (it has electronic ignition but still needs checking periodically). I just assume it's "one of them things" and keep my foot firmly on the kickstart; this seems to minimise the actual kickback.
Intigued to see the timing tool, must buy one next time I visit Burwins, I currently use calibrated coffee stirrers and a little digital multimeter to find the point where the voltage changes!

[space-ritual]

I use a comparator dial guage, the plunger type, I find that this sits nicely in the cup shaped area of the head on my Supafive and needs no screwing in, I find TDC and then back it off, then I approach TDC and stop .120" before TDC. I use a multimeter to adjust the points to the correct position. I always find that the bike kicks back, so I've tried it in other positions with the same result. The main trouble with my bike is that it runs rich and fouls up the plugs but that's a different story.

[Skorpion]

Hi space-ritual,

Your setting your points at the maximum advance .120'' = 3mm,
You really don't want it this advanced because as the plastic heal on the points wear it will advance further,
at 3mm plus you will definitely get kick back.
Your points should be set to 100'' = 2.5mm or even better on some engines 80'' = 2mm this should lesson or stop the kick back and make the engine run smoother and cooler,

Skorpion

15 years on TS250 & ETZ 250-300

Sorry bob griff, I cant help you as I have no knowledge of 125s

[space-ritual]

Thanks for the reply, I'll try it again at the weekend.
Just one question though, in the manual it mentions bob weights for the timing advance and to make sure that these are wedged back during the setting, I don't seem to have them. Where would they be?

[Skorpion]

The TS250 Super Five has fixed timing, I think the bob weights were on an earlier model,