1999 Yamaha 115 2 stroke choke plates(butterfly)

[vettman]

Noticed my '99 115 2stroke is hard starting when cold. Choke plates have holes in them therefore not creating a rich enough mixture to fire the motor. Took some duct tape and carefully taped over the holes. No problem with cold starts any longer. Have an older 1987 115 with plates that are solid, no holes ,and has always started cold. Why would Yamaha change a good thing by making choke plates with holes in them and therefore creating hard starts. In old school a choke completely closes of incoming air to making a richer mixture to easily start a cold motor.

 

[99yam40]

need air also to mix with the fuel.
it has to get into the motor some how

 

[vettman]

I agree to some extent. But it fires right up now that the holes are blocked off. The plates are closing fully, but with the holes it's not allowing for a rich enough cold start mixture.

 

[ondarvr]

They designed the motor to start when new, 17 years later things may have changed enough to make it harder to start, or its just not tuned correctly.