algaib

Even though you guys provide the answers (the reason people post on forums) I must quote myself from that thread; "Turned out that the float valve in the carb was stuck from the residue of old petrol. I cleaned it up, along with the jets and voila! Happy running engine " to which you yourself replied; "So I guess a 'thank you' would be in order." How is that not a finished thread? Anyway, thanks for the advice.

My bike passed the MOT yesterday but now it seems there is a part missing from the carburettor which I didn't spot before. Can anyone tell me what should be there, and how important is it? Images at http://www.theabominablesnowman.co.uk/DT125.html Thanks

I kept the float height within spec according to the service manual. The fuel is coming out of the overflow pipe coming from the bottom of the float chamber. If there is crud in the valve seat or main jet, wouldn't the fuel be coming from a different overflow pipe? Or do they both go to the same place? Also, if the problem was in the main jet, wouldn't the engine just rev up like crazy? When the bike is running, it de-accelerates fine as normal.

I have just taken a Yamaha DT 125R out of storage. I removed the carburettor and cleaned away all the residue. It now works like a dream, except that about 10 minutes after I turn off the engine, the overflow pipe starts dripping. The overflow needle valve is in good condition (no sign of damage and looks like new) and I have adjusted the float height to make it more sensitive to the overflow, but still the problem persists. I have looked at buying a new overflow needle valve, but the cheapest quote I have found is £50, which seems rediculous for a tiny piece of alloy. Any suggestions? Or perhaps do you know a dealer that supplies these parts at a more reasonable price?

Turned out that the float valve in the carb was stuck from the residue of old petrol. I cleaned it up, along with the jets and voila! Happy running engine

I've had a DT 125 in storage for a few years. Of course it didn't start. I cleaned out the petrol tank which was full of debris; rust I guess. The filter on the tap is also now clean. I put some petrol in the spark plug hole, connected it to another bike's battery to jump start it. It whent for a second or two, but as soon as the fuel I injected burned, the engine stopped. I tried to bump start it a few times; no joy. But then it suddenly did start and it ran for a few seconds and shot out plumes of white smoke. This happened a few times, but always stopped after a few seconds. I would guess that the fuel isn't going from the carb to the spark plug properly. Any ideas? Also, do you need the battery for it to run? Because the one on it is shot.