Hi, I have been using this site as well as Clymers.  I'm disassembling the carb to give it a cleaning.  

I have found the Main jet is a 155, and the pilot jet says 47.5 on the side.  This is a 93 Canadian bike, from the specs listed on this site that probably is stock.  The pilot air jet says 230 for whatever that's worth.  I'm at sea level, cold weather riding, should I leave the settings alone?  FWIW I have to get a new pilot jet anyway since I damaged it getting it out..

I cannot get the main needle jet out(?)...I removed the main jet, and the washer, but I'm afraid of damaging the needle jet.  It should remove inside towards the carb throat right?  Not towards the bowl? Does it screw out or just push out?

Also someone else stripped the screws holding the plate in the way of removing the choke pull.  The choke seems clean and works, will I be sorry if I don't try and get it out after all to clean it?

Thanks for any advice..

stewmills wrote on 10/28/19 at 13:52:34:


Nope, the needle jet pushes up away from the bowl.

The main jet unscrews towards the bowl.

Keifer wrote on 10/28/19 at 14:00:41:


Generally nothing as the black coating is dry lube, although I use injector cleaner in the gas and last time I took it out it was wet with it.
So when I put it back in, I just applied a couple of drops and wiped it around.

I bought it as a project, it had been sitting outside for some time.  It would run, but not idle.  Had to constantly feather the throttle, and it backfires.  So I've never had it 'running' enough to see if it needs jetting.  I will just replace the jets with the same sizes... once its cleaned (hopefully I don't screw it up) and see from there.  I finally got the parts in the mail...

In the below photo... what is this hole's function?  It is completely plugged.

Hole 3.  Just need to know if these should be free and clear...

I believe that hole in the throat of the carburetor (hole #1) is your main air bleed jet.  I'm sorry to disagree with you Gary, but I don't think it's part of the idle circuit.

The Main Air Bleed affects your mixture at higher throttle positions.  It works in conjunction with the Main Jet.  A larger air bleed will delay the onset of the main circuit and also lean out the mixture by admitting more air to the emulsion tube (needle jet).  Larger air bleed, leaner mixture; smaller air bleed, richer mixture; plugged air bleed, super-rich mixture.

If it is completely obstructed, you must clean it out.  It is a fixed jet (i.e. pressed into the carburetor body) so you can't remove it.  Gary is right to caution you about poking stuff in that jet.  But alas, sometimes there's just no other way.  If you can't clear the obstruction with carb cleaner, you may have to resort to mechanical cleaning.

The main air bleed is .024" (.6mm).  That is equivalent to a #73 drill bit.  I know, I know, drill bits can be real bad news for a jet.  But if its plugged with hard crud, you may have no other choice but to resort to some sort of hard implement.  If you have to clear it mechanically, I suggest you use the back end of a #74 or a #73 drill bit.  Not the pointed side, the blunt side.  As long as you don't use anything larger than a #73, you shouldn't enlarge the jet.  You just have to be careful.  You don't wanna remove metal, you just wanna remove crud.  BTW, I have found that PineSol softens up old fuel crud quite nicely.  I know that sounds crazy but it actually works.  Note that micro-drills are wire gage, so a #73 (.0240") is larger in diameter than a #74 (.0225").

Keep in mind that when you push the crud out of that air bleed, it's gonna go into the air passage behind the jet.  That passage leads to the cavity that surrounds the needle jet (AKA emulsion tube).  You should remove the needle jet before you clear the air bleed.  That way, when you break the crud loose it has a path for exit from the carb body.  Flush it good with carb cleaner, spraying through the air bleed from the inlet side of the carb towards the throttle plate.

Hole #3 is a mystery hole.  It is factory-plugged with a brass rod.  It appears to me to be a feature of the manufacturing process.  You will see plugs in various other areas on the carburetor.  They drill passages that intersect at different angles, then plug an opening where the drill entered or exited.  It looks to me like they drilled a passage and then plugged it with a brass rod.  You have probably noticed the brass rod running up & down through the venturi of your carburetor.  Its actually a plug.

Look familiar?

Keifer wrote on 11/17/19 at 11:29:50:
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If the bike is stock, then I would make sure the jets currently installed are still stock or close to stock.  The reason being is that you know the bike should run reasonably well with stock jetting.  This lets you focus on the things that might be causing it to run poorly (like your clogged passages).  

I mention this because you never know what someone else did to the bike before you got it and you have no idea how well it ran when they parked it.  Stock jetting is a nice place to start unless the bike has a lot of performance mods.