Also ..........my own personal experience ........every 500 miles .........I throw
some Seafoam in the tank to clean out the carb's .......the easy way ...real good
stuff ......10 bucks napa / walmart

 

In the middle of this process, cleaning the jets. The pilot/idle jet has tiny holes along the side. They are clear now.

But the jet may still be clogged. If I look in one end of the jet, should I be able to see light from the other end? Should I be able to put a wire all the way through, end to end?

Never done this before, don't want to smeg it up.

Craig

 

G'Day Craig,

Ideally you shouldn't be cleaning jest with wire.. Carb cleaner, petrol and compressed air for the disassembled jets.

Did some reading about this over a coffee this morning and am more confused than when I started.

The pilot bleed jet when it has holes in the side is an emulsion tube. On some websites (mainly for big single cylinder thumpers) they suggested that there was a hole in the bottom of the jet. Others did not.

Either way, best to blow out the obstruction.

Cheers, SB

 

Thanks. But what is an emulsion jet? All four of these jets are clogged--or else they are supposed to be that way. I can't imagine four jets clogged in exactly the same way, but I also can't figure out how any gas gets through. There are holes on the sides of the jets, in the thinner, inward end, and holes at each end. They've been soaking in carb cleaner a good while. So I'm baffled.

Craig

 

aka pilot jets and no the end hole and all side holes are supposed to be unclogged

indicative of a rusting tank ! finer rust gets past the filter and clogs the pilot / emulsion jets
as they are more miniscule and have a much slower flow rate and are not used much after
3k rpm

 

Haven't checked out the tank yet; bike has been sitting about a year, and there's a good bit of gunk in the carbs. One float valve was totally stuck. I'll be cleaning--and maybe coating--the tank and fuel lines next.

The holes on the sides and the ends of the pilot jets are clear. There seems to be a blockage in the middle, where the large and small ends of the jets meet. On all four jets.

Shouldn't there be a hole there? This may be the dumbest question in the history of the motorcycle, but if there's no hole, I'll quit trying to clean it. If there is, I won't put the carbs back in until I get new jets. I should be able to look into one end of the jet and see light, right?

I need my big bike back. My '87 Magna just doesn't have enough power.

Craig

 

^ If you are talking about the brass jets that you have removed, YES. They need to be clear. It is that hole size in the middle that runs the length of it that determines how much fuel is metered into the carb.

No hole = no fuel

 

Yes, the brass pilot jets that I have removed and soaked in carb cleaner for 24 hours.

Thanks. Time for new jets.

Craig

 

So time for new jets. Keihin 40S. What is the S for? Anyone know a good source?

Craig