Jump to content

Right cylinder cutting out


jamaha51

Recommended Posts

I just got a banshee on a trade the other day.  The right cylinder would cut out when it hit the powerband so I started checking it out.  The tors has been cut out, the cylinders are within 3 psi of eachother, switched sparkplug wires,  and the reeds are decent (a couple pedals have a tiny gap).  I went through the carbs and adjusted the throttle cable so its even.  Its all stock besides the pipes and no airbox.  After I went through it i did a couple 1st through 6th passes up the street and it seemed to run good.  I shut it off for a few minutes then fired it back up and it started cutting out and it just got worse the more i ran it.  So go back out this morning and its still cutting out bad.  So i check the plug gap (running br8es'), adjust the airscrews and the idle and it ran better but still cut out at high rpms.  I do a plug chop(plugs were a nice brown) and switch the plugs.  Doesnt seem to help.  Its really starting to frustrate me cuz it will run ok one minute then cut out the next.  Im thinking airleak but im not really sure?

Link to comment
Share on other sites

The left carb has a small brass BB peened into the bowl... ONLY the left carb has this...

Not on the 87 and 89 that I own. Both bowls look the same from the outside. Some setups have brass tubes in both bowls as well. what you need to look for is the little indent in front of the brass tube. one indent is open and the other bowl will have the same indent but its plugged by the casting. the indent that is open will be the left carb bowl and the plugged indent is the right side.

 

The choke works by pulling fuel into the brass tube via the open indent and transferring it to the right carb via the rubber choke tube that people forget to install.

Link to comment
Share on other sites

Photo of the BB in the float bowel.

6497F5A8-BA00-4868-8ED0-68B4FA6AA550-143

 

Indent/hole that fuel is sucked into the brass tube.

DE799848-65C8-4DC6-AC89-C2D49AB25E9F-143

 

Right side bowel has identical indent/hole. You need to shine a light into it to see which one is open. No light? That's okay. Just suck on each brass tube until you find the one that doesn't have resistance and that's the left side bowel.

DE799848-65C8-4DC6-AC89-C2D49AB25E9F-143

Link to comment
Share on other sites

  • 11 months later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...