1980 Yamaha SS440 BOG!!

[longtrack156]

How well does a stock Yamaha 1980 SS440 run. My grandson has one, completely stock, and the bog on takeoff is really bad, is that the way they were? Any suggestions?

 

[catssuk]

im guessing a bad streched out belt..push down on it if it flexes more than a inch or so its shot.. chris

 

[longtrack156]

So they have good bottom end if everything else is good?

 

[Snow Duck]

carbs clean??

 

[longtrack156]

It is a single carb, yes it has been cleaned thoroughly, the trouble is, I don't know if they were any good new, a lot of sleds back then had poor bottom end. If the ss440 was good back in the day then we can try some stuff. The sled was bought used last year and we dont know what it is supposed to run like.
I don't even know what the engagement rpm is, (no tach), I will try belt, engagement rpm first. I hate the thought of trying to make something run better when it never did.

 

[Snow Duck]

THEY WERE THE CHIZ IN THE DAY...they dont have a ton of power but are a reliable...as posted above start with the belt if the carb is clean..how are the plugs ect...choke adj correct and air screws set just a few more to check...

 

[northerngn]

check the pilot jet... slightly drilling mine out helped tons! now, when i crack the throttle on mine and if the snow is hard packed enough the skis raise right up!!!
goes from 1500 idle to 6500 right now!
-Dan