Carburettor servicing part 1 – removal

If you manage to find yourself an old AG200 that has been lying around in a shed for a year or two and you want to try and get it going, take my advice – don’t bother! Not until you have cleaned the carburettor out anyway. Unless the farmer who owned it was a maintenance ninja (um…yeah) and drained the fuel out before laying it up in the shed, then the carb will be a mess and even if you do manage fire it up, it will suck all sorts of rubbish into the engine. Read on AG200 ninjas…

Float bowl drain
Drain float bowl
Choke plunger
Remove choke

First thing to do obviously is to remove the carb from the bike. Lots of bits can be removed to help in this so start with the fuel tank and the seat. I also like to remove the exhaust system. You can do it with it in place but it’s a pain. Another thing that makes it way easier when its out of the way is the rear shock and spring assembly, but unless you are doing a full strip down then leave it in place.


Cable removal
Throttle cable
Front manifold
Front clamp

Before removing the carby, I like to release the drain screw on the bottom of the float bowl to remove the fuel (if any) that may be left in it. It will save you getting covered in fuel when you remove the carb from the bike and you can let it drain while you remove the other bits. Place something under the bike to catch the old fuel. Stale fuel stinks and the smell lingers and seriously does not agree with me.

Rear manifold
Rear clamp
remove carb

First thing to remove is the choke cable and plunger. A 14mm open end spanner will help you with this. Then remove the throttle cable using a 10mm spanner to loosen off the adjusters in the bracket assembly.

Loosen off the two clamps holding the rubber manifolds on at the front and rear of the carb. Pull the carb to the rear to release it, the rear rubber manifold is a lot more flexible than the front so you can mash it up a bit to help get the unit free and out of the bike.

On the bench

When removing the carb, take note of where the overflow hose is routed and its relationship with other wiring that lives near it, It may help you getting it back together neatly without kinking hoses and so forth. You might want to stuff a rag in the inlet manifold while doing this work too.

There we go, part one down and the carb is out and on the work bench. Keep an eye here to read about the meaty bit of stripping down the carb.




17 thoughts on “Carburettor servicing part 1 – removal

  1. Hey, I got 2 AG200’s, have just rebuilt a CDI, and am about to tackle the carby tomorrow!.. Look forward to your update… kinda wish you had posted it already, as I sure could use some pointers.


    1. Hi Trevor
      Thanks for the comments. Carb dissemble is coming soon…but my damn camera has died! You shouldn’t have many problems with the carby, just get it all stripped down as far as you can…I cheat a bit – I use an ultra-sonic cleaner to do it which I will document in the next post…keep watching here!

  2. Aah AGMan, don’t think you even have to take off the seat or tank. I was able to take off and replace fairly easily (although tank was removed at the time). I undid the clamp to the airbox, and removed the 2 allen key bolts to the engine and removed. To replace, do so from the right hand side of the bike. First insert with the engine port side facing straight ahead (at 90 degrees to it’s usual position), then push the carb into the airbox pipe. And position the carb onto the engine – doesn’t take long at all.

    1. Hi Tej
      There are always more ways to skin a cat. I always take the seat and tank off to do anything, doesn’t take long…Its just my way of working on the bike, and it always seemed to help me with access to cables and stuff like that. Removing the manifold from the head is probably a good idea as well – nice work.

  3. Just wondefine if you had any tips on getting the choke plunger out? I ‘inherited’ a bike on a farm I bought. Full of stale fuel and a seized choke. Bike won’t start. I have the carby out in as much as it’s hanging by the choke cable. Nut undone, plunger stuck…..

    Cheers Chris

    1. Hi Chris
      Common problem you have there. First off it’s probably easier to work on the carb off the bike so you can release the choke knob assembly off the handlebar and thread the cable down through the frame (remove seat and tank) and locating bands/tabs. The only way I have removed jammed plungers is with patience and time. If you break the cable you are in a world of pain! Mount the carb somewhere on a workbench and squirt CRC/WD40 into the plunger and all other pathways that appear to lead to the choke circuit, you should see these circuits as you pull the carby down. Check out the pics in my carb servicing posts to help if you need them. try and work the plunger free – sometimes its taken me hours, sometimes its taken me days!
      I’ll give you a heads up; if the plunger has seized and all the circuits are blocked, you will have to go all the way with the carb clean like in my tutorial, if you don’t have the gear or cant be bothered, keep an eye out for a second hand carb. You should be able to judge for yourself on your path – if the float bowl area is in really bad condition you are in for a fight! If it’s not too bad then it worth giving it a try.

      1. Thanks. I have a neighbour with an ultrasonic cleaner, so I’m thinking that’s where its going to end up..

          1. Agman, finally got the plunger out. The carb is suprisingingly clean with only a residue of what looked like fine outback red dust. The plunger is damaged on top, with one of the brass ‘tabs’ on top broken off. So i guess it’s time for a new plunger. Do you know what model carb it is?

          2. Hi Chris
            You can look the part up at Trooper Lu and you will see it comes in a 5 piece kit – 36X-1410A-00, they call it a starter set and will charge you over $60 for it. If that hurts too much then Id say contact someone on eBay wrecking an AG and see if they will separate one out for you, or ask someone selling an AG200 carb if they have the choke – most don’t have it in the sale. There is one guy on eBay selling a whole carb for $30 at the moment but there doesn’t appear to be a choke in it. A quick message to him might sort it out for you.
            Might be easier just to drop the money for the kit with all the new parts. You could ring around the dealers because most are cheaper than Trooper, but few have an online listing of parts in Australia, unlike the US.

  4. Hi again AGMan

    Had taken out and fully serviced a carb and replaced it and right away had a seized choke. How is that possible? I’ve unscrewed the choke cable but can’t remove it. Would it be the plunger or spring that’s jammed and why? Going to try the WD40 tomorrow. Do you have to open up the carb and clean it out after or not? As I’d rather not remove the carb to do that. Also, from your experience, how long does a bike have to sit before carbs go awry?

    1. Hi Tej
      It looks like there might of been a bit of grit left in the choke plunger section, that’s all I can think of. Its something I missed mentioning in my carb rebuild post that a bit of light oil on the plunger helps in its operation. Be patient trying to remove it and unless you see a lot of rubbish on it then you should be able to just clean it up and reassemble. Makes sure the pin is clean as well as the piston body of the plunger.
      As for the fuel in carb issue, it depends on the quality of your fuel. My rule of thumb was that if any of my bikes were going to sit for more than a week, I would drain the fuel from carb via the drain screw in the fuel bowl.

      1. Thanks! Managed to finally remove that goddamned plunger and still not sure why it was so stuck! Took the carb and entire choke off the bike. One of the bikes I’ve been riding has been consistently surging a bit at WOT. Was at Yamaha today and a mech pointed out that the rubber manifold on the head side was damaged and likely letting air in causing the problem. Costs $50+ just for that part dammit! I noticed the rubber manifolds on my other 2 AG’s (all 2003) are pretty loose around the manifold where it screws into the head. Is this a common issue? Any fixes like duct tape over it?

        1. Hi Tej
          There are no cheap fixes for the manifold unfortunately, there are cheaper aftermarket options from China but people have had mixed results with them. It is common for them to crack and let air into the engine which doesn’t do it a lot of good.
          There is this example from China but I have never tried them, they look OK in the photo you could make them an offer for three!

  5. Aah thanks for that AGMan.. didn’t have time to explore that option, got it from the dealer. The other two manifolds rubbers were a little loose – and the carb was pretty easy to move about – are they on their way out or already there?

  6. Hi AGMan, Mate I’m not sure whether I’ve created a dinosaur or what? everything I touch on this old chook chaser I find a problem, except the tyres hahaha they’re black and round. I am or was having issues with my carburettor until I got back on here and guess what? I’m not alone thank god, I thought I was jinxed. choke stuck, internals stuck, needle and seat stuck, float stuck it goes on and on. What I was interested in finding out was is there a complete rebuild kit I can buy for this? cheers.
    This is the most informative site bar none, keep up the good work, Thanks

    1. Hi Bruce
      Thanks for the comments. There is no rebuild kit that I know of and I probably wouldn’t recommend it if there was unless it was genuine Yamaha. The generic kits on Ebay etc are generally rubbish. If your carb is as bad as you say, I would have a look around for a late model wrecker. The problem with the AG carb is that it has a lot of little passages for air and fuel flow and if they are neglected and allowed to block, they are a real pain to get working correctly again. You see the extent I go to in my tutorials and some times that doesn’t work! If the bike is as bad as you say, this is one part of it that may continue to give you grief…I’d look for another carb.

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