markbec2
New member
I bought the sled with the carb off, I reinstalled it I can get the sled to run with the choke on but it runs super rough, and starts to run rougher after a minute or two then lightly backfires and quits any simple ideas?
Thanks
Thanks
SpartaSXr
Member
Carb
Pull the carb back off and clean it. It sounds like the main jet or the pilot may be gunked up . Make sure the pulse hose is connected to the crank case.
Pull the carb back off and clean it. It sounds like the main jet or the pilot may be gunked up . Make sure the pulse hose is connected to the crank case.
Ding
Darn Tootin'
That should be a Keihin diaphragm carb on there. Did you adjust the fuel level at the sight tube? Rebuilding a diaphragm carb is a little more involved and tedious than a slide carb. The adjustment process is as follows . . .
- Back off the adjuster nut on the bolt in the bottom of the carb. If you have had it apart or are unsure of it's current setting - six full turns in is a starting point. Start the sled and adjust the fuel level until it is at the joint between the carb body and the pump body. Be sure to control idle speed during this step as it affects the level. I have found that 4 1/2 - 5 1/2 turns in (from falling out) is usually where it ends up. Be sure to tighten the locknut well as these bolts like to loosen and fall out.
- Adjust the idle mixture screw until the engine runs the best and then open it a little (1/8 - 1/4) turn to aid acceleration.
- Readjust the idle speed to 2000 rpm's - I use a Tiny Tach for this.
Ding
Darn Tootin'
I have one doing the same thing right now. It was running fine for most of last year, but at the end of the year it began to flood. I still haven't found the problem. These can be finicky buggers.
markbec2
New member
Thanks so much!! I am heading out right now to try it out printed off your steps.
sandmanmike1
New member
The screw in the bottom of the carb on these is famous for dropping out. That wouls cause some problems. Easy to check. If the screw is gone goodluck finding a aftermarket one. I am in the process of switching over to a mikuni roundslide due to unavailabilty of screw.
Maim
Super Moderator
Ding said:I have one doing the same thing right now. It was running fine for most of last year, but at the end of the year it began to flood. I still haven't found the problem. These can be finicky buggers.
ding, take it off and check the diaprams. we have a 79 and if you filled it up it would flood the motor. under 1/2 tank it was ok. just hope you do not have the "other" carb like i do. aparently yamaha put 2 different cabs on this sled. i just happen to have the rare large one.