Question about 1973 Yamaha DT 360

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I have a 74 dt360, original with 1100m miles. Engine will start on choke and run a few cycles, then die. Carb is clean, all passages are open. Occasionally, there is a backfire out the exhaust, and then the engine starts on the next kick, but still only runs a few cycles. There seems to be no response to readjusting the lo and mid range air bleeds. There is a good, strong spark.

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Im a little unsure about your lo and mid air bleeds.
It should have an idle speed screw and an idle mixture screw.
The mixture screw should be set around 1 3\4 turns out from the full in position. The idle speed screw should start at a point where it just starts to lift the carb slide.
make sure the air filter element is clean and there is no wasp nest or blockage in the exhaust , as it has obviously not been used much in 36 years. They always needed a pretty good kick to get them started, Will it roll start ? Also I cant remember if that model had a decompressor valve which may have carboned up

Posted on Sep 12, 2010


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Motor will start but I have to manually hold the choke open until it warms up otherwise choke closes on its own

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Check/replace the fuel filter.

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You are correct, the mixture needs altering.

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