Page 1 of 1

yamaha genesis 80 fi

PostPosted: Thu Feb 26, 2009 5:01 am
by boostein
Has anybody tuned this engine with the m4 yet? I'm having an extremely hard time getting the timing set on this motor. I'm starting to wonder if the m4 even has the ability to run this engine. I've already used a degree wheel to ensure that the odd fires are 0, 180, and those are set in the Motec. My sync rel pos % is right around 50%. ref/sync mode is rise/rise, and I have verified the goodness of this setting with a four channel oscilloscope. The problem is that the engine does not want to run on both cylinders with the correct crip setting. The way I'm setting the crip is with the spark plugs removed, and cranking with a timing light and test advance set to 0. With this method, I'm getting a crip of 430, and the engine won't run on both cylinders unless the crip is around 380. I'm running out of ideas here.

Re: yamaha genesis 80 fi

PostPosted: Thu Feb 26, 2009 8:52 am
by IDP
I wouldn't rely on your timing light while cranking, they're not accurate a low uneven cranking speeds.

I would physically measure the crip with a degree wheel. Then start the engine and trim it with a timing light.

Re: yamaha genesis 80 fi

PostPosted: Sat Feb 28, 2009 7:24 am
by micke r1
is genesis 80 fi .........a five valve 800 cc fuel inj snow mobile engine ?

Re: yamaha genesis 80 fi

PostPosted: Thu Mar 05, 2009 3:22 am
by boostein
it is indeed a five valve motor, although it is 500cc.

Re: yamaha genesis 80 fi

PostPosted: Tue Mar 17, 2009 4:30 pm
by RossB
Have you manually measured the CRIP as IDP has suggested?